Programs & Examples On #http status code 415

How to get HttpClient returning status code and response body?

BasicResponseHandler throws if the status is not 2xx. See its javadoc.

Here is how I would do it:

HttpResponse response = client.execute( get );
int code = response.getStatusLine().getStatusCode();
InputStream body = response.getEntity().getContent();
// Read the body stream

Or you can also write a ResponseHandler starting from BasicResponseHandler source that don't throw when the status is not 2xx.

REST HTTP status codes for failed validation or invalid duplicate

A duplicate in the database should be a 409 CONFLICT.

I recommend using 422 UNPROCESSABLE ENTITY for validation errors.

I give a longer explanation of 4xx codes here.

How to return a 200 HTTP Status Code from ASP.NET MVC 3 controller

200 is just the normal HTTP header for a successful request. If that's all you need, just have the controller return new EmptyResult();

Return HTTP status code 201 in flask

You can do

result = {'a': 'b'}
return jsonify(result), 201

if you want to return a JSON data in the response along with the error code You can read about responses here and here for make_response API details

AngularJS POST Fails: Response for preflight has invalid HTTP status code 404

You have enabled CORS and enabled Access-Control-Allow-Origin : * in the server.If still you get GET method working and POST method is not working then it might be because of the problem of Content-Type and data problem.

First AngularJS transmits data using Content-Type: application/json which is not serialized natively by some of the web servers (notably PHP). For them we have to transmit the data as Content-Type: x-www-form-urlencoded

Example :-

        $scope.formLoginPost = function () {
            $http({
                url: url,
                method: "POST",
                data: $.param({ 'username': $scope.username, 'Password': $scope.Password }),
                headers: { 'Content-Type': 'application/x-www-form-urlencoded' }
            }).then(function (response) {
                // success
                console.log('success');
                console.log("then : " + JSON.stringify(response));
            }, function (response) { // optional
                // failed
                console.log('failed');
                console.log(JSON.stringify(response));
            });
        };

Note : I am using $.params to serialize the data to use Content-Type: x-www-form-urlencoded. Alternatively you can use the following javascript function

function params(obj){
    var str = "";
    for (var key in obj) {
        if (str != "") {
            str += "&";
        }
        str += key + "=" + encodeURIComponent(obj[key]);
    }
    return str;
}

and use params({ 'username': $scope.username, 'Password': $scope.Password }) to serialize it as the Content-Type: x-www-form-urlencoded requests only gets the POST data in username=john&Password=12345 form.

Getting Http Status code number (200, 301, 404, etc.) from HttpWebRequest and HttpWebResponse

//Response being your httpwebresponse
Dim str_StatusCode as String = CInt(Response.StatusCode)
Console.Writeline(str_StatusCode)

How do I get the HTTP status code with jQuery?

The third argument is the XMLHttpRequest object, so you can do whatever you want.

$.ajax({
  url  : 'http://example.com',
  type : 'post',
  data : 'a=b'
}).done(function(data, statusText, xhr){
  var status = xhr.status;                //200
  var head = xhr.getAllResponseHeaders(); //Detail header info
});

JAX-RS — How to return JSON and HTTP status code together?

The answer by hisdrewness will work, but it modifies the whole approach to letting a provider such as Jackson+JAXB automatically convert your returned object to some output format such as JSON. Inspired by an Apache CXF post (which uses a CXF-specific class) I've found one way to set the response code that should work in any JAX-RS implementation: inject an HttpServletResponse context and manually set the response code. For example, here is how to set the response code to CREATED when appropriate.

@Path("/foos/{fooId}")
@PUT
@Consumes("application/json")
@Produces("application/json")
public Foo setFoo(@PathParam("fooID") final String fooID, final Foo foo, @Context final HttpServletResponse response)
{
  //TODO store foo in persistent storage
  if(itemDidNotExistBefore) //return 201 only if new object; TODO app-specific logic
  {
    response.setStatus(Response.Status.CREATED.getStatusCode());
  }
  return foo;  //TODO get latest foo from storage if needed
}

Improvement: After finding another related answer, I learned that one can inject the HttpServletResponse as a member variable, even for singleton service class (at least in RESTEasy)!! This is a much better approach than polluting the API with implementation details. It would look like this:

@Context  //injected response proxy supporting multiple threads
private HttpServletResponse response;

@Path("/foos/{fooId}")
@PUT
@Consumes("application/json")
@Produces("application/json")
public Foo setFoo(@PathParam("fooID") final String fooID, final Foo foo)
{
  //TODO store foo in persistent storage
  if(itemDidNotExistBefore) //return 201 only if new object; TODO app-specific logic
  {
    response.setStatus(Response.Status.CREATED.getStatusCode());
  }
  return foo;  //TODO get latest foo from storage if needed
}

Laravel - Return json along with http status code

You can use http_response_code() to set HTTP response code.

If you pass no parameters then http_response_code will get the current status code. If you pass a parameter it will set the response code.

http_response_code(201); // Set response status code to 201

For Laravel(Reference from: https://stackoverflow.com/a/14717895/2025923):

return Response::json([
    'hello' => $value
], 201); // Status code here

Does an HTTP Status code of 0 have any meaning?

Short Answer

It's not a HTTP response code, but it is documented by WhatWG as a valid value for the status attribute of an XMLHttpRequest or a Fetch response.

Broadly speaking, it is a default value used when there is no real HTTP status code to report and/or an error occurred sending the request or receiving the response. Possible scenarios where this is the case include, but are not limited to:

  • The request hasn't yet been sent, or was aborted.
  • The browser is still waiting to receive the response status and headers.
  • The connection dropped during the request.
  • The request timed out.
  • The request encountered an infinite redirect loop.
  • The browser knows the response status, but you're not allowed to access it due to security restrictions related to the Same-origin Policy.

Long Answer

First, to reiterate: 0 is not a HTTP status code. There's a complete list of them in RFC 7231 Section 6.1, that doesn't include 0, and the intro to section 6 states clearly that

The status-code element is a three-digit integer code

which 0 is not.

However, 0 as a value of the .status attribute of an XMLHttpRequest object is documented, although it's a little tricky to track down all the relevant details. We begin at https://xhr.spec.whatwg.org/#the-status-attribute, documenting the .status attribute, which simply states:

The status attribute must return the response’s status.

That may sound vacuous and tautological, but in reality there is information here! Remember that this documentation is talking here about the .response attribute of an XMLHttpRequest, not a response, so this tells us that the definition of the status on an XHR object is deferred to the definition of a response's status in the Fetch spec.

But what response object? What if we haven't actually received a response yet? The inline link on the word "response" takes us to https://xhr.spec.whatwg.org/#response, which explains:

An XMLHttpRequest has an associated response. Unless stated otherwise it is a network error.

So the response whose status we're getting is by default a network error. And by searching for everywhere the phrase "set response to" is used in the XHR spec, we can see that it's set in five places:

Looking in the Fetch standard, we can see that:

A network error is a response whose status is always 0

so we can immediately tell that we'll see a status of 0 on an XHR object in any of the cases where the XHR spec says the response should be set to a network error. (Interestingly, this includes the case where the body's stream gets "errored", which the Fetch spec tells us can happen during parsing the body after having received the status - so in theory I suppose it is possible for an XHR object to have its status set to 200, then encounter an out-of-memory error or something while receiving the body and so change its status back to 0.)

We also note in the Fetch standard that a couple of other response types exist whose status is defined to be 0, whose existence relates to cross-origin requests and the same-origin policy:

An opaque filtered response is a filtered response whose ... status is 0...

An opaque-redirect filtered response is a filtered response whose ... status is 0...

(various other details about these two response types omitted).

But beyond these, there are also many cases where the Fetch algorithm (rather than the XHR spec, which we've already looked at) calls for the browser to return a network error! Indeed, the phrase "return a network error" appears 40 times in the Fetch standard. I will not try to list all 40 here, but I note that they include:

  • The case where the request's scheme is unrecognised (e.g. trying to send a request to madeupscheme://foobar.com)
  • The wonderfully vague instruction "When in doubt, return a network error." in the algorithms for handling ftp:// and file:// URLs
  • Infinite redirects: "If request’s redirect count is twenty, return a network error."
  • A bunch of CORS-related issues, such as "If httpRequest’s response tainting is not "cors" and the cross-origin resource policy check with request and response returns blocked, then return a network error."
  • Connection failures: "If connection is failure, return a network error."

In other words: whenever something goes wrong other than getting a real HTTP error status code like a 500 or 400 from the server, you end up with a status attribute of 0 on your XHR object or Fetch response object in the browser. The number of possible specific causes enumerated in spec is vast.

Finally: if you're interested in the history of the spec for some reason, note that this answer was completely rewritten in 2020, and that you may be interested in the previous revision of this answer, which parsed essentially the same conclusions out of the older (and much simpler) W3 spec for XHR, before these were replaced by the more modern and more complicated WhatWG specs this answers refers to.

Should a 502 HTTP status code be used if a proxy receives no response at all?

Yes. Empty or incomplete headers or response body typically caused by broken connections or server side crash can cause 502 errors if accessed via a gateway or proxy.

For more information about the network errors

https://en.wikipedia.org/wiki/List_of_HTTP_status_codes

Right HTTP status code to wrong input

We had the same problem when making our API as well. We were looking for an HTTP status code equivalent to an InvalidArgumentException. After reading the source article below, we ended up using 422 Unprocessable Entity which states:

The 422 (Unprocessable Entity) status code means the server understands the content type of the request entity (hence a 415 (Unsupported Media Type) status code is inappropriate), and the syntax of the request entity is correct (thus a 400 (Bad Request) status code is inappropriate) but was unable to process the contained instructions. For example, this error condition may occur if an XML request body contains well-formed (i.e., syntactically correct), but semantically erroneous, XML instructions.

source: https://www.bennadel.com/blog/2434-http-status-codes-for-invalid-data-400-vs-422.htm

How can I get the status code from an http error in Axios?

As @Nick said, the results you see when you console.log a JavaScript Error object depend on the exact implementation of console.log, which varies and (imo) makes checking errors incredibly annoying.

If you'd like to see the full Error object and all the information it carries bypassing the toString() method, you could just use JSON.stringify:

axios.get('/foo')
  .catch(function (error) {
    console.log(JSON.stringify(error))
  });

Spring Boot Rest Controller how to return different HTTP status codes?

There are several options you can use. Quite good way is to use exceptions and class for handling called @ControllerAdvice:

@ControllerAdvice
class GlobalControllerExceptionHandler {
    @ResponseStatus(HttpStatus.CONFLICT)  // 409
    @ExceptionHandler(DataIntegrityViolationException.class)
    public void handleConflict() {
        // Nothing to do
    }
}

Also you can pass HttpServletResponse to controller method and just set response code:

public RestModel create(@RequestBody String data, HttpServletResponse response) {
    // response committed...
    response.setStatus(HttpServletResponse.SC_ACCEPTED);
}

Please refer to the this great blog post for details: Exception Handling in Spring MVC


NOTE

In Spring MVC using @ResponseBody annotation is redundant - it's already included in @RestController annotation.

Script to get the HTTP status code of a list of urls?

wget -S -i *file* will get you the headers from each url in a file.

Filter though grep for the status code specifically.

What HTTP status response code should I use if the request is missing a required parameter?

I often use a 403 Forbidden error. The reasoning is that the request was understood, but I'm not going to do as asked (because things are wrong). The response entity explains what is wrong, so if the response is an HTML page, the error messages are in the page. If it's a JSON or XML response, the error information is in there.

From rfc2616:

10.4.4 403 Forbidden

The server understood the request, but is refusing to fulfill it.
Authorization will not help and the request SHOULD NOT be repeated.
If the request method was not HEAD and the server wishes to make
public why the request has not been fulfilled, it SHOULD describe the reason for the refusal in the entity. If the server does not wish to make this information available to the client, the status code 404
(Not Found) can be used instead.

Why is AJAX returning HTTP status code 0?

In my troubleshooting, I found this AJAX xmlhttpRequest.status == 0 could mean the client call had NOT reached the server yet, but failed due to issue on the client side. If the response was from server, then the status must be either those 1xx/2xx/3xx/4xx/5xx HTTP Response code. Henceforth, the troubleshooting shall focus on the CLIENT issue, and could be internet network connection down or one of those described by @Langdon above.

What's an appropriate HTTP status code to return by a REST API service for a validation failure?

If "validation failure" means that there is some client error in the request, then use HTTP 400 (Bad Request). For instance if the URI is supposed to have an ISO-8601 date and you find that it's in the wrong format or refers to February 31st, then you would return an HTTP 400. Ditto if you expect well-formed XML in an entity body and it fails to parse.

(1/2016): Over the last five years WebDAV's more specific HTTP 422 (Unprocessable Entity) has become a very reasonable alternative to HTTP 400. See for instance its use in JSON API. But do note that HTTP 422 has not made it into HTTP 1.1, RFC-7231.

Richardson and Ruby's RESTful Web Services contains a very helpful appendix on when to use the various HTTP response codes. They say:

400 (“Bad Request”)
Importance: High.
This is the generic client-side error status, used when no other 4xx error code is appropriate. It’s commonly used when the client submits a representation along with a PUT or POST request, and the representation is in the right format, but it doesn’t make any sense. (p. 381)

and:

401 (“Unauthorized”)
Importance: High.
The client tried to operate on a protected resource without providing the proper authentication credentials. It may have provided the wrong credentials, or none at all. The credentials may be a username and password, an API key, or an authentication token—whatever the service in question is expecting. It’s common for a client to make a request for a URI and accept a 401 just so it knows what kind of credentials to send and in what format. [...]

Returning http status code from Web Api controller

Try this :

return new ContentResult() { 
    StatusCode = 404, 
    Content = "Not found" 
};

System.Net.WebException HTTP status code

this works only if WebResponse is a HttpWebResponse.

try
{
    ...
}
catch (System.Net.WebException exc)
{
    var webResponse = exc.Response as System.Net.HttpWebResponse;
    if (webResponse != null && 
        webResponse.StatusCode == System.Net.HttpStatusCode.Unauthorized)
    {
        MessageBox.Show("401");
    }
    else
        throw;
}

HTTP status code for update and delete?

Here's some status code, which you should know for your kind of knowledge.

1XX Information Responses

  • 100 Continue
  • 101 Switching Protocols
  • 102 Processing
  • 103 Early Hints

2XX Success

  • 200 OK
  • 201 Created
  • 202 Accepted
  • 203 Non-Authoritative Information
  • 204 No Content
  • 205 Reset Content
  • 206 Partial Content
  • 207 Multi-Status
  • 208 Already Reported
  • 226 IM Used

3XX Redirection

  • 300 Multiple Choices
  • 301 Moved Permanently
  • 302 Found
  • 303 See Other
  • 304 Not Modified
  • 305 Use Proxy
  • 306 Switch Proxy
  • 307 Temporary Redirect
  • 308 Permanent Redirect

4XX Client errors

  • 400 Bad Request
  • 401 Unauthorized
  • 402 Payment Required
  • 403 Forbidden
  • 404 Not Found
  • 405 Method Not Allowed
  • 406 Not Acceptable
  • 407 Proxy Authentication Required
  • 408 Request Timeout
  • 409 Conflict
  • 410 Gone
  • 411 Length Required
  • 412 Precondition Failed
  • 413 Payload Too Large
  • 414 URI Too Long
  • 415 Unsupported Media Type
  • 416 Range Not Satisfiable
  • 417 Expectation Failed
  • 418 I'm a teapot
  • 420 Method Failure
  • 421 Misdirected Request
  • 422 Unprocessable Entity
  • 423 Locked
  • 424 Failed Dependency
  • 426 Upgrade Required
  • 428 Precondition Required
  • 429 Too Many Requests
  • 431 Request Header Fields Too Large
  • 451 Unavailable For Legal Reasons

5XX Server errors

  • 500 Internal Server error
  • 501 Not Implemented
  • 502 Bad Gateway
  • 503 Service Unavailable
  • 504 gateway Timeout
  • 505 Http version not supported
  • 506 Varient Also negotiate
  • 507 Insufficient Storage
  • 508 Loop Detected
  • 510 Not Extended
  • 511 Network Authentication Required

Swift Alamofire: How to get the HTTP response status code

For Swift 3.x / Swift 4.0 / Swift 5.0 users with Alamofire >= 5.0

Used request modifier to increase and decrease the timeout interval.

Alamofire's request creation methods offer the most common parameters for customization but sometimes those just aren't enough. The URLRequests created from the passed values can be modified by using a RequestModifier closure when creating requests. For example, to set the URLRequest's timeoutInterval to 120 seconds, modify the request in the closure.

var manager = Session.default
 manager.request(urlString, method: method, parameters: dict, headers: headers, requestModifier: { $0.timeoutInterval = 120 }).validate().responseJSON { response in

OR

RequestModifiers also work with trailing closure syntax.

var manager = Session.default
     manager.request("https://httpbin.org/get") { urlRequest in
    urlRequest.timeoutInterval = 60
    urlRequest.allowsConstrainedNetworkAccess = false
}
.response(...)

POST JSON fails with 415 Unsupported media type, Spring 3 mvc

I believe I ran exactly into the same issue. After countless hours of fighting with the JSON, the JavaScript and the Server, I found the culprit: In my case I had a Date object in the DTO, this Date object was converted to a String so we could show it in the view with the format: HH:mm.

When JSON information was being sent back, this Date String object had to be converted back into a full Date Object, therefore we also need a method to set it in the DTO. The big BUT is you cannot have 2 methods with the same name (Overload) in the DTO even if they have different type of parameter (String vs Date) because this will give you also the 415 Unsupported Media type error.

This was my controller method

  @RequestMapping(value = "/alarmdownload/update", produces = "application/json", method = RequestMethod.POST)
  public @ResponseBody
  StatusResponse update(@RequestBody AlarmDownloadDTO[] rowList) {
    System.out.println("hola");
    return new StatusResponse();
  }

This was my DTO example (id get/set and preAlarm get Methods are not included for code shortness):

@JsonIgnoreProperties(ignoreUnknown = true)
public class AlarmDownloadDTO implements Serializable {

  private static final SimpleDateFormat formatHHmm = new SimpleDateFormat("HH:mm");

  private String id;
  private Date preAlarm;

  public void setPreAlarm(Date date) { 
    this.preAlarm == date;
  }
  public void setPreAlarm(String date) {    
    try {
      this.preAlarm = formatHHmm.parse(date);
    } catch (ParseException e) {
      this.preAlarm = null;
    } catch (NullPointerException e){
      this.preAlarm = null;
    }
  }
}

To make everything work you need to remove the method with Date type parameter. This error is very frustrating. Hope this can save someone hours of debugging.

How to deal with http status codes other than 200 in Angular 2

Include required imports and you can make ur decision in handleError method Error status will give the error code

import { HttpClient, HttpErrorResponse } from '@angular/common/http';
import {Observable, throwError} from "rxjs/index";
import { catchError, retry } from 'rxjs/operators';
import {ApiResponse} from "../model/api.response";
import { TaxType } from '../model/taxtype.model'; 

private handleError(error: HttpErrorResponse) {
if (error.error instanceof ErrorEvent) {
  // A client-side or network error occurred. Handle it accordingly.
  console.error('An error occurred:', error.error.message);
} else {
  // The backend returned an unsuccessful response code.
  // The response body may contain clues as to what went wrong,
  console.error(
    `Backend returned code ${error.status}, ` +
    `body was: ${error.error}`);
}
// return an observable with a user-facing error message
return throwError(
  'Something bad happened; please try again later.');
  };

  getTaxTypes() : Observable<ApiResponse> {
return this.http.get<ApiResponse>(this.baseUrl).pipe(
  catchError(this.handleError)
);
  }

jQuery: How to get the HTTP status code from within the $.ajax.error method?

If you're using jQuery 1.5, then statusCode will work.

If you're using jQuery 1.4, try this:

error: function(jqXHR, textStatus, errorThrown) {
    alert(jqXHR.status);
    alert(textStatus);
    alert(errorThrown);
}

You should see the status code from the first alert.

HTTP status code 0 - Error Domain=NSURLErrorDomain?

From my limited experience, I would say that the following two scenario could cause response status code: 0, keep in mind; their could be more, but I know of those two:

  • your connection maybe responding slowly.
  • or maybe the the back-end server is not available.

the thing is, status: 0 is slightly generic, and their could be more use cases that trigger an empty response body.

HTTP 415 unsupported media type error when calling Web API 2 endpoint

SOLVED
After banging my head on the wall for a couple days with this issue, it was looking like the problem had something to do with the content type negotiation between the client and server. I dug deeper into that using Fiddler to check the request details coming from the client app, here's a screenshot of the raw request as captured by fiddler:

Fiddler capture of http request from client app

What's obviously missing there is the Content-Type header, even though I was setting it as seen in the code sample in my original post. I thought it was strange that the Content-Type never came through even though I was setting it, so I had another look at my other (working) code calling a different Web API service, the only difference was that I happened to be setting the req.ContentType property prior to writing to the request body in that case. I made that change to this new code and that did it, the Content-Type was now showing up and I got the expected success response from the web service. The new code from my .NET client now looks like this:

req.Method = "POST"
req.ContentType = "application/json"
lstrPagingJSON = JsonSerializer(Of Paging)(lPaging)
bytData = Encoding.UTF8.GetBytes(lstrPagingJSON)
req.ContentLength = bytData.Length
reqStream = req.GetRequestStream()
reqStream.Write(bytData, 0, bytData.Length)
reqStream.Close()
'// Content-Type was being set here, causing the problem
'req.ContentType = "application/json"

That's all it was, the ContentType property just needed to be set prior to writing to the request body

I believe this behavior is because once content is written to the body it is streamed to the service endpoint being called, any other attributes pertaining to the request need to be set prior to that. Please correct me if I'm wrong or if this needs more detail.

What is the difference between HTTP status code 200 (cache) vs status code 304?

200 (cache) means Firefox is simply using the locally cached version. This is the fastest because no request to the Web server is made.

304 means Firefox is sending a "If-Modified-Since" conditional request to the Web server. If the file has not been updated since the date sent by the browser, the Web server returns a 304 response which essentially tells Firefox to use its cached version. It is not as fast as 200 (cache) because the request is still sent to the Web server, but the server doesn't have to send the contents of the file.

To your last question, I don't know why the two JavaScript files in the same directory are returning different results.

Job for httpd.service failed because the control process exited with error code. See "systemctl status httpd.service" and "journalctl -xe" for details

In my case I got the error simply because I had changed the Listen 80 to listen 443 in the file

/etc/httpd/conf/httpd.conf 

Since I had installed mod_ssl using the yum commands

yum -y install mod_ssl  

there was a duplicate listen 443 directive in the file ssl.conf created during mod_ssl installation.

You can verify this if you have duplicate listen 80 or 443 by running the below command in linux centos (My linux)

grep  '443' /etc/httpd/conf.d/*

below is sample output

/etc/httpd/conf.d/ssl.conf:Listen 443 https
/etc/httpd/conf.d/ssl.conf:<VirtualHost _default_:443>
/etc/httpd/conf.d/ssl.conf:#ServerName www.example.com:443

Simply reverting the listen 443 in httd.conf to listen 80 fixed my issue.

Http 415 Unsupported Media type error with JSON

I was sending "delete" rest request and it failed with 415. I saw what content-type my server uses to hit the api. In my case, It was "application/json" instead of "application/json; charset=utf8".

So ask from your api developer And in the meantime try sending request with content-type= "application/json" only.

Curl to return http status code along with the response

This is a way to retrieve the body "AND" the status code and format it to a proper json or whatever format works for you. Some may argue it's the incorrect use of write format option but this works for me when I need both body and status code in my scripts to check status code and relay back the responses from server.

curl -X GET -w "%{stderr}{\"status\": \"%{http_code}\", \"body\":\"%{stdout}\"}"  -s -o - “https://github.com” 2>&1

run the code above and you should get back a json in this format:

{
"status" : <status code>,
"body" : <body of response>
}

with the -w write format option, since stderr is printed first, you can format your output with the var http_code and place the body of the response in a value (body) and follow up the enclosing using var stdout. Then redirect your stderr output to stdout and you'll be able to combine both http_code and response body into a neat output

How do I detect whether a Python variable is a function?

Python's 2to3 tool (http://docs.python.org/dev/library/2to3.html) suggests:

import collections
isinstance(obj, collections.Callable)

It seems this was chosen instead of the hasattr(x, '__call__') method because of http://bugs.python.org/issue7006.

Cleaning up old remote git branches

This command will "dry run" delete all remote (origin) merged branches, apart from master. You can change that, or, add additional branches after master: grep -v for-example-your-branch-here |

git branch -r --merged | 
  grep origin | 
  grep -v '>' | 
  grep -v master | 
  xargs -L1 | 
  awk '{sub(/origin\//,"");print}'| 
  xargs git push origin --delete --dry-run

If it looks good, remove the --dry-run. Additionally, you may like to test this on a fork first.

Javascript to convert UTC to local time

To format your date try the following function:

var d = new Date();
var fromatted = d.toLocaleFormat("%d.%m.%Y %H:%M (%a)");

But the downside of this is, that it's a non-standard function, which is not working in Chrome, but working in FF (afaik).

Chris

How to increase the distance between table columns in HTML?

Set the width of the <td>s to 50px and then add your <td> + another fake <td>

Fiddle.

_x000D_
_x000D_
table tr td:empty {_x000D_
  width: 50px;_x000D_
}_x000D_
  _x000D_
table tr td {_x000D_
  padding-top: 10px;_x000D_
  padding-bottom: 10px;_x000D_
}
_x000D_
<table>_x000D_
  <tr>_x000D_
    <td>First Column</td>_x000D_
    <td></td>_x000D_
    <td>Second Column</td>_x000D_
    <td></td>_x000D_
    <td>Third Column</td>_x000D_
  </tr>_x000D_
</table>
_x000D_
_x000D_
_x000D_

Code Explained:

The first CSS rule checks for empty td's and give them a width of 50px then the second rule give the padding of top and bottom to all the td's.

CodeIgniter Select Query

public function getSalary()
    {
        $this->db->select('tbl_salary.*,tbl_employee.empFirstName');
        $this->db->from('tbl_salary');
        $this->db->join('tbl_employee','tbl_employee.empID = strong texttbl_salary.salEmpID');
        $this->db->where('tbl_salary.status',0);
        $query = $this->db->get();
        return $query->result();
    }

running php script (php function) in linux bash

Simply this should do:

php test.php

Deleting queues in RabbitMQ

I was struggling with finding an answer that suited my needs of manually delete a queue in rabbigmq. I therefore think it is worth mentioning in this thread that it is possible to delete a single queue without rabbitmqadmin using the following command:

rabbitmqctl delete_queue <queue_name>

How to handle the new window in Selenium WebDriver using Java?

i was having some issues with windowhandle and tried this one. this one works good for me.

String parentWindowHandler = driver.getWindowHandle(); 
String subWindowHandler = null;

Set<String> handles = driver.getWindowHandles();
Iterator<String> iterator = handles.iterator();
while (iterator.hasNext()){
    subWindowHandler = iterator.next();
    driver.switchTo().window(subWindowHandler);

    System.out.println(subWindowHandler);
}


driver.switchTo().window(parentWindowHandler); 

'printf' with leading zeros in C

Your format specifier is incorrect. From the printf() man page on my machine:

0 A zero '0' character indicating that zero-padding should be used rather than blank-padding. A '-' overrides a '0' if both are used;

Field Width: An optional digit string specifying a field width; if the output string has fewer characters than the field width it will be blank-padded on the left (or right, if the left-adjustment indicator has been given) to make up the field width (note that a leading zero is a flag, but an embedded zero is part of a field width);

Precision: An optional period, '.', followed by an optional digit string giving a precision which specifies the number of digits to appear after the decimal point, for e and f formats, or the maximum number of characters to be printed from a string; if the digit string is missing, the precision is treated as zero;

For your case, your format would be %09.3f:

#include <stdio.h>

int main(int argc, char **argv)
{
  printf("%09.3f\n", 4917.24);
  return 0;
}

Output:

$ make testapp
cc     testapp.c   -o testapp
$ ./testapp 
04917.240

Note that this answer is conditional on your embedded system having a printf() implementation that is standard-compliant for these details - many embedded environments do not have such an implementation.

'import' and 'export' may only appear at the top level

I am using Webpack 2.2.0 to bundle my React JS modules.

Encountered a similar issue while importing modules in my main app.js file.

After 30 minutes of headbanging I updated the RegEx for testing the file types in my webpack.config.js.

Carefully notice the ? symbol in test RegEx query.

{
    test: /\.js?$/,
    exclude: /(node_modules)/,
    loader: 'react-hot-loader'
}

It worked for me !!

Letsencrypt add domain to existing certificate

Apache on Ubuntu, using the Apache plugin:

sudo certbot certonly --cert-name example.com -d m.example.com,www.m.example.com

The above command is vividly explained in the Certbot user guide on changing a certificate's domain names. Note that the command for changing a certificate's domain names applies to adding new domain names as well.

Edit

If running the above command gives you the error message

Client with the currently selected authenticator does not support any combination of challenges that will satisfy the CA.

follow these instructions from the Let's Encrypt Community

Best way to work with transactions in MS SQL Server Management Studio

The easisest thing to do is to wrap your code in a transaction, and then execute each batch of T-SQL code line by line.

For example,

Begin Transaction

         -Do some T-SQL queries here.

Rollback transaction -- OR commit transaction

If you want to incorporate error handling you can do so by using a TRY...CATCH BLOCK. Should an error occur you can then rollback the tranasction within the catch block.

For example:

USE AdventureWorks;
GO
BEGIN TRANSACTION;

BEGIN TRY
    -- Generate a constraint violation error.
    DELETE FROM Production.Product
    WHERE ProductID = 980;
END TRY
BEGIN CATCH
    SELECT 
        ERROR_NUMBER() AS ErrorNumber
        ,ERROR_SEVERITY() AS ErrorSeverity
        ,ERROR_STATE() AS ErrorState
        ,ERROR_PROCEDURE() AS ErrorProcedure
        ,ERROR_LINE() AS ErrorLine
        ,ERROR_MESSAGE() AS ErrorMessage;

    IF @@TRANCOUNT > 0
        ROLLBACK TRANSACTION;
END CATCH;

IF @@TRANCOUNT > 0
    COMMIT TRANSACTION;
GO

See the following link for more details.

http://msdn.microsoft.com/en-us/library/ms175976.aspx

Hope this helps but please let me know if you need more details.

SQL - The conversion of a varchar data type to a datetime data type resulted in an out-of-range value

I too encountered this issue while auto inserting a sysdate to a column.

What I did is I changed my system date format to match with SQL server's date format. e.g. my SQL format was mm/dd/yyyy and my system format was set to dd/mm/yyyy. I changed my system format to mm/dd/yyyy and error gone

-kb

2 column div layout: right column with fixed width, left fluid

See http://www.alistapart.com/articles/negativemargins/ , this is exactly what you need (example 4 there).

<div id="container">
    <div id="content">
        <h1>content</h1>
        <p>Lorem ipsum dolor sit amet, consectetuer adipiscing elit.  Phasellus varius eleifend tellus. Suspendisse potenti. Class aptent taciti sociosqu ad litora torquent per conubia nostra, per inceptos hymenaeos. Nulla facilisi. Sed wisi lectus, placerat nec, mollis quis, posuere eget, arcu.</p>
        <p class="last">Donec euismod. Praesent mauris mi, adipiscing non, mollis eget, adipiscing ac, erat. Integer nonummy mauris sit amet metus. In adipiscing, ligula ultrices dictum vehicula, eros turpis lacinia libero, sed aliquet urna diam sed tellus. Etiam semper sapien eget metus.</p>
    </div>
</div>

<div id="sidebar">
    <h1>sidebar</h1>
    <ul>
        <li>link one</li>
        <li>link two</li>
    </ul>
</div>

#container {
    width: 100%;
    background: #f1f2ea url(background.gif) repeat-y right;
    float: left;
    margin-right: -200px;
}
#content {
    background: #f1f2ea;
    margin-right: 200px;
}
#sidebar {
    width: 200px;
    float: right;

How to uninstall Ruby from /usr/local?

do this way :

sudo apt purge ruby

How do you plot bar charts in gnuplot?

plot "data.dat" using 2: xtic(1) with histogram

Here data.dat contains data of the form

title 1
title2 3
"long title" 5

Displaying better error message than "No JSON object could be decoded"

I had a similar problem this was my code:

    json_file=json.dumps(pyJson)
    file = open("list.json",'w')
    file.write(json_file)  

    json_file = open("list.json","r")
    json_decoded = json.load(json_file)
    print json_decoded

the problem was i had forgotten to file.close() I did it and fixed the problem.

How to delete columns in pyspark dataframe

You could either explicitly name the columns you want to keep, like so:

keep = [a.id, a.julian_date, a.user_id, b.quan_created_money, b.quan_created_cnt]

Or in a more general approach you'd include all columns except for a specific one via a list comprehension. For example like this (excluding the id column from b):

keep = [a[c] for c in a.columns] + [b[c] for c in b.columns if c != 'id']

Finally you make a selection on your join result:

d = a.join(b, a.id==b.id, 'outer').select(*keep)

Fastest way to iterate over all the chars in a String

The first one using str.charAt should be faster.

If you dig inside the source code of String class, we can see that charAt is implemented as follows:

public char charAt(int index) {
    if ((index < 0) || (index >= count)) {
        throw new StringIndexOutOfBoundsException(index);
    }
    return value[index + offset];
}

Here, all it does is index an array and return the value.

Now, if we see the implementation of toCharArray, we will find the below:

public char[] toCharArray() {
    char result[] = new char[count];
    getChars(0, count, result, 0);
    return result;
}

public void getChars(int srcBegin, int srcEnd, char dst[], int dstBegin) {
    if (srcBegin < 0) {
        throw new StringIndexOutOfBoundsException(srcBegin);
    }
    if (srcEnd > count) {
        throw new StringIndexOutOfBoundsException(srcEnd);
    }
    if (srcBegin > srcEnd) {
        throw new StringIndexOutOfBoundsException(srcEnd - srcBegin);
    }
    System.arraycopy(value, offset + srcBegin, dst, dstBegin,
         srcEnd - srcBegin);
}

As you see, it is doing a System.arraycopy which is definitely going to be a tad slower than not doing it.

How to use a filter in a controller?

It seems nobody has mentioned that you can use a function as arg2 in $filter('filtername')(arg1,arg2);

For example:

$scope.filteredItems = $filter('filter')(items, function(item){return item.Price>50;});

How do I set the driver's python version in spark?

I got the same issue on standalone spark in windows. My version of fix is like this: I had my environment variables setting as bellow

PYSPARK_SUBMIT_ARGS="pyspark-shell"
PYSPARK_DRIVER_PYTHON=jupyter
PYSPARK_DRIVER_PYTHON_OPTS='notebook' pyspark

With this setting I executed an Action on pyspark and got the following exception:

Python in worker has different version 3.6 than that in driver 3.5, PySpark cannot run with different minor versions.
Please check environment variables PYSPARK_PYTHON and PYSPARK_DRIVER_PYTHON are correctly set.

To check with which python version my spark-worker is using hit the following in the cmd prompt.

python --version
Python 3.6.3

which showed me Python 3.6.3. So clearly my spark-worker is using system python which is v3.6.3.

Now as I set my spark-driver to run jupyter by setting PYSPARK_DRIVER_PYTHON=jupyter so I need to check the python version jupyter is using.

To do this check open Anaconda Prompt and hit

python --version
Python 3.5.X :: Anaconda, Inc.

Here got the jupyter python is using the v3.5.x. You can check this version also in any Notebook (Help->About).

Now I need to update the jupyter python to the version v3.6.6. To do that open up the Anaconda Prompt and hit

conda search python

This will give you a list of available python versions in Anaconda. Install your desired one with

conda install python=3.6.3

Now I have both of the Python installation of same version 3.6.3 Spark should not comply and it didn't when I ran an Action on Spark-driver. Exception is gone. Happy coding ...

JavaScript: client-side vs. server-side validation

If you are doing light validation, it is best to do it on the client. It will save the network traffic which will help your server perform better. If if it complicated validation that involves pulling data from a database or something, like passwords, then it best to do it on the server where the data can be securely checked.

Vertical Alignment of text in a table cell

I had the same issue but solved it by using !important. I forgot about the inheritance in CSS. Just a tip to check first.

How to test if a string contains one of the substrings in a list, in pandas?

You can use str.contains alone with a regex pattern using OR (|):

s[s.str.contains('og|at')]

Or you could add the series to a dataframe then use str.contains:

df = pd.DataFrame(s)
df[s.str.contains('og|at')] 

Output:

0 cat
1 hat
2 dog
3 fog 

Select a row from html table and send values onclick of a button

$("#table tr").click(function(){
   $(this).addClass('selected').siblings().removeClass('selected');    
   var value=$(this).find('td:first').html();
   alert(value);    
});

$('.ok').on('click', function(e){
    alert($("#table tr.selected td:first").html());
});

Demo:

http://jsfiddle.net/65JPw/2/

Set value of textarea in jQuery

Just use this code and you will always have the value:

var t = $(this); var v = t.val() || t.html() || t.text();

So it will check val() and set its value. If val() gets an empty string, NULL, NaN o.s. it will check for html() and then for text()...

Test if a vector contains a given element

I will group the options based on output. Assume the following vector for all the examples.

v <- c('z', 'a','b','a','e')

For checking presence:

%in%

> 'a' %in% v
[1] TRUE

any()

> any('a'==v)
[1] TRUE

is.element()

> is.element('a', v)
[1] TRUE

For finding first occurance:

match()

> match('a', v)
[1] 2

For finding all occurances as vector of indices:

which()

> which('a' == v)
[1] 2 4

For finding all occurances as logical vector:

==

> 'a' == v
[1] FALSE  TRUE FALSE  TRUE FALSE

Edit: Removing grep() and grepl() from the list for reason mentioned in comments

Resolving require paths with webpack

resolve.alias should work exactly the way you described, so I'm providing this as an answer to help mitigate any confusion that may result from the suggestion in the original question that it does not work.

a resolve configuration like the one below will give you the desired results:

// used to resolve absolute path to project's root directory (where web pack.config.js should be located)
var path = require( 'path' );
...
{
  ...
  resolve: {
    // add alias for application code directory
    alias:{
      mydir: path.resolve( __dirname, 'path', 'to', 'mydir' )
    },
    extensions: [ '', '.js' ]
  }
}

require( 'mydir/myfile.js' ) will work as expected. If it does not, there must be some other issue.

If you have multiple modules that you want to add to the search path, resolve.root makes sense, but if you just want to be able to reference components within your application code without relative paths, alias seems to be the most straight-forward and explicit.

An important advantage of alias is that it gives you the opportunity to namespace your requires which can add clarity to your code; just like it is easy to see from other requires what module is being referenced, alias allows you to write descriptive requires that make it obvious you're requiring internal modules, e.g. require( 'my-project/component' ). resolve.root just plops you into the desired directory without giving you the opportunity to namespace it further.

Row was updated or deleted by another transaction (or unsaved-value mapping was incorrect)

In order to prevent StaleObjectStateException, in your hbm file write below code:

<timestamp name="lstUpdTstamp" column="LST_UPD_TSTAMP" source="db"/>

Regex to accept alphanumeric and some special character in Javascript?

I forgot to mention. This should also accept whitespace.

You could use:

/^[-@.\/#&+\w\s]*$/

Note how this makes use of the character classes \w and \s.

EDIT:- Added \ to escape /

IndexError: index 1 is out of bounds for axis 0 with size 1/ForwardEuler

The problem, as the Traceback says, comes from the line x[i+1] = x[i] + ( t[i+1] - t[i] ) * f( x[i], t[i] ). Let's replace it in its context:

  • x is an array equal to [x0 * n], so its length is 1
  • you're iterating from 0 to n-2 (n doesn't matter here), and i is the index. In the beginning, everything is ok (here there's no beginning apparently... :( ), but as soon as i + 1 >= len(x) <=> i >= 0, the element x[i+1] doesn't exist. Here, this element doesn't exist since the beginning of the for loop.

To solve this, you must replace x[i+1] = x[i] + ( t[i+1] - t[i] ) * f( x[i], t[i] ) by x.append(x[i] + ( t[i+1] - t[i] ) * f( x[i], t[i] )).

How to integrate SAP Crystal Reports in Visual Studio 2017

To integrate SAP Crystal Reports with Visual Studio 2017 below steps needs to be followed right:

  • Uninstall all installed components from system related to Crystal Report. [If any]
  • Install compatible Crystal Report Developer Edition (as per target VS) with administrator priviledge. [As of writing, latest compatible service pack is 23]
    • Install appropriate Crystal Report Runtime (x86/ x64) for Visual Studio. [Not mandatory]
  • Open solution in VS and remove all assembly references from project related to Crystal Report. [If any]
  • Include following assembly references in project:
    • CrystalDecisions.CrystalReports.Engine
    • CrystalDecisions.ReportSource
    • CrystalDecisions.Shared
    • CrystalDecisions.CrystalReports.Design
    • CrystalDecisions.VSDesigner
  • Make sure "Copy Local" property is set to "True" in reference properties.
  • Build/ Rebuild project.

Why does 'git commit' not save my changes?

Maybe an obvious thing, but...

If you have problem with the index, use git-gui. You get a very good view how the index (staging area) actually works.

Another source of information that helped me understand the index was Scott Chacons "Getting Git" page 259 and forward.

I started off using the command line because most documentation only showed that...

I think git-gui and gitk actually make me work faster, and I got rid of bad habits like "git pull" for example... Now I always fetch first... See what the new changes really are before I merge.

How to know that a string starts/ends with a specific string in jQuery?

ES6 now supports the startsWith() and endsWith() method for checking beginning and ending of strings. If you want to support pre-es6 engines, you might want to consider adding one of the suggested methods to the String prototype.

if (typeof String.prototype.startsWith != 'function') {
  String.prototype.startsWith = function (str) {
    return this.match(new RegExp("^" + str));
  };
}

if (typeof String.prototype.endsWith != 'function') {
  String.prototype.endsWith = function (str) {
    return this.match(new RegExp(str + "$"));
  };
}

var str = "foobar is not barfoo";
console.log(str.startsWith("foob"); // true
console.log(str.endsWith("rfoo");   // true

Node package ( Grunt ) installed but not available

Add /usr/local/share/npm/bin/ to your $PATH

ggplot with 2 y axes on each side and different scales

We definitely could build a plot with dual Y-axises using base R funtion plot.

# pseudo dataset
df <- data.frame(x = seq(1, 1000, 1), y1 = sample.int(100, 1000, replace=T), y2 = sample(50, 1000, replace = T))

# plot first plot 
with(df, plot(y1 ~ x, col = "red"))

# set new plot
par(new = T) 

# plot second plot, but without axis
with(df, plot(y2 ~ x, type = "l", xaxt = "n", yaxt = "n", xlab = "", ylab = ""))

# define y-axis and put y-labs
axis(4)
with(df, mtext("y2", side = 4))

Decimal values in SQL for dividing results

just convert denominator to decimal before division e.g

select col1 / CONVERT(decimal(4,2), col2) from tbl1

How to remove unused imports in Intellij IDEA on commit?

In IntelliJ, select the project you want to optimize imports on, go to Code menu and choose Optimize imports and a small Optimize Imports popup window will appear. On the popup window you need to click on Run button. Or alternatively, on IntelliJ on Mac, you can use a keyboard short cut Option + Command + O

Get data from file input in JQuery

input file element:

<input type="file" id="fileinput" />

get file :

var myFile = $('#fileinput').prop('files');

Removing path and extension from filename in PowerShell

This can be done by splitting the string a couple of times.

#Path
$Link = "http://some.url/some/path/file.name"

#Split path on "/"
#Results of split will look like this : 
# http:
#
# some.url
# some
# path
# file.name
$Split = $Link.Split("/")

#Count how many Split strings there are
#There are 6 strings that have been split in my example
$SplitCount = $Split.Count

#Select the last string
#Result of this selection : 
# file.name
$FilenameWithExtension = $Split[$SplitCount -1]

#Split filename on "."
#Result of this split : 
# file
# name
$FilenameWithExtensionSplit = $FilenameWithExtension.Split(".")

#Select the first half
#Result of this selection : 
# file
$FilenameWithoutExtension = $FilenameWithExtensionSplit[0]

#The filename without extension is in this variable now
# file
$FilenameWithoutExtension

Here is the code without comments :

$Link = "http://some.url/some/path/file.name"
$Split = $Link.Split("/")
$SplitCount = $Split.Count
$FilenameWithExtension = $Split[$SplitCount -1]
$FilenameWithExtensionSplit = $FilenameWithExtension.Split(".")
$FilenameWithoutExtension = $FilenameWithExtensionSplit[0]
$FilenameWithoutExtension

SQL JOIN vs IN performance?

Each database's implementation but you can probably guess that they all solve common problems in more or less the same way. If you are using MSSQL have a look at the execution plan that is generated. You can do this by turning on the profiler and executions plans. This will give you a text version when you run the command.

I am not sure what version of MSSQL you are using but you can get a graphical one in SQL Server 2000 in the query analyzer. I am sure that this functionality is lurking some where in SQL Server Studio Manager in later versions.

Have a look at the exeuction plan. As far as possible avoid table scans unless of course your table is small in which case a table scan is faster than using an index. Read up on the different join operations that each different scenario produces.

Send POST request using NSURLSession

If you are using Swift, the Just library does this for you. Example from it's readme file:

//  talk to registration end point
Just.post(
    "http://justiceleauge.org/member/register",
    data: ["username": "barryallen", "password":"ReverseF1ashSucks"],
    files: ["profile_photo": .URL(fileURLWithPath:"flash.jpeg", nil)]
) { (r)
    if (r.ok) { /* success! */ }
}

How to make a floated div 100% height of its parent?

I made an example resolving your problem.

You have to make a wrapper, float it, then position absolute your div and give to it 100% height.

HTML

<div class="container">
    <div class="left">"Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum." </div>
  <div class="right-wrapper">
    <div class="right">"Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua." </div>
  </div>
  <div class="clear">&nbsp;</div>
</div>

CSS:

.container {
    width: 100%;
    position:relative;
}
.left {
    width: 50%;
    background-color: rgba(0, 0, 255, 0.6);
    float: left;
}
.right-wrapper {
    width: 48%;
    float: left;
}
.right {
    height: 100%;
    position: absolute;
}

Explanation: The .right div is absolutely positioned. That means that its width and height, and top and left positiones will be calculed based on the first parent div absolutely or relative positioned ONLY if width or height properties are explicitly declared in CSS; if they aren't explicty declared, those properties will be calculed based on the parent container (.right-wrapper).

So, the 100% height of the DIV will be calculed based on .container final height, and the final position of .right position will be calculed based on the parent container.

Is Visual Studio Community a 30 day trial?

VS 17 Community Edition is free. You just need to sign-in with your Microsoft account and everything will be fine again.

Draw text in OpenGL ES

Rendering text to a texture is simpler than what the Sprite Text demo make it looks like, the basic idea is to use the Canvas class to render to a Bitmap and then pass the Bitmap to an OpenGL texture:

// Create an empty, mutable bitmap
Bitmap bitmap = Bitmap.createBitmap(256, 256, Bitmap.Config.ARGB_4444);
// get a canvas to paint over the bitmap
Canvas canvas = new Canvas(bitmap);
bitmap.eraseColor(0);

// get a background image from resources
// note the image format must match the bitmap format
Drawable background = context.getResources().getDrawable(R.drawable.background);
background.setBounds(0, 0, 256, 256);
background.draw(canvas); // draw the background to our bitmap

// Draw the text
Paint textPaint = new Paint();
textPaint.setTextSize(32);
textPaint.setAntiAlias(true);
textPaint.setARGB(0xff, 0x00, 0x00, 0x00);
// draw the text centered
canvas.drawText("Hello World", 16,112, textPaint);

//Generate one texture pointer...
gl.glGenTextures(1, textures, 0);
//...and bind it to our array
gl.glBindTexture(GL10.GL_TEXTURE_2D, textures[0]);

//Create Nearest Filtered Texture
gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_MIN_FILTER, GL10.GL_NEAREST);
gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_MAG_FILTER, GL10.GL_LINEAR);

//Different possible texture parameters, e.g. GL10.GL_CLAMP_TO_EDGE
gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_WRAP_S, GL10.GL_REPEAT);
gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_WRAP_T, GL10.GL_REPEAT);

//Use the Android GLUtils to specify a two-dimensional texture image from our bitmap
GLUtils.texImage2D(GL10.GL_TEXTURE_2D, 0, bitmap, 0);

//Clean up
bitmap.recycle();

Check a radio button with javascript

Today, in the year 2016, it is save to use document.querySelector without knowing the ID (especially if you have more than 2 radio buttons):

document.querySelector("input[name=main-categories]:checked").value

How do I wait for an asynchronously dispatched block to finish?

I have to wait until a UIWebView is loaded before running my method, I was able to get this working by performing UIWebView ready checks on main thread using GCD in combination with semaphore methods mentioned in this thread. Final code looks like this:

-(void)myMethod {

    if (![self isWebViewLoaded]) {

            dispatch_semaphore_t semaphore = dispatch_semaphore_create(0);

            __block BOOL isWebViewLoaded = NO;

            dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{

                while (!isWebViewLoaded) {

                    dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)((0.0) * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
                        isWebViewLoaded = [self isWebViewLoaded];
                    });

                    [NSThread sleepForTimeInterval:0.1];//check again if it's loaded every 0.1s

                }

                dispatch_sync(dispatch_get_main_queue(), ^{
                    dispatch_semaphore_signal(semaphore);
                });

            });

            while (dispatch_semaphore_wait(semaphore, DISPATCH_TIME_NOW)) {
                [[NSRunLoop currentRunLoop] runMode:NSDefaultRunLoopMode beforeDate:[NSDate dateWithTimeIntervalSinceNow:0]];
            }

        }

    }

    //Run rest of method here after web view is loaded

}

SQL Server loop - how do I loop through a set of records

By using T-SQL and cursors like this :

DECLARE @MyCursor CURSOR;
DECLARE @MyField YourFieldDataType;
BEGIN
    SET @MyCursor = CURSOR FOR
    select top 1000 YourField from dbo.table
        where StatusID = 7      

    OPEN @MyCursor 
    FETCH NEXT FROM @MyCursor 
    INTO @MyField

    WHILE @@FETCH_STATUS = 0
    BEGIN
      /*
         YOUR ALGORITHM GOES HERE   
      */
      FETCH NEXT FROM @MyCursor 
      INTO @MyField 
    END; 

    CLOSE @MyCursor ;
    DEALLOCATE @MyCursor;
END;

How to move files from one git repo to another (not a clone), preserving history

The below method to migrate my GIT Stash to GitLab by maintaining all branches and preserving history.

Clone the old repository to local.

git clone --bare <STASH-URL>

Create an empty repository in GitLab.

git push --mirror <GitLab-URL>

The above I performed when we migrated our code from stash to GitLab and it worked very well.

Angular cookies

Use NGX Cookie Service

Inastall this package: npm install ngx-cookie-service --save

Add the cookie service to your app.module.ts as a provider:

import { CookieService } from 'ngx-cookie-service';
@NgModule({
  declarations: [ AppComponent ],
  imports: [ BrowserModule, ... ],
  providers: [ CookieService ],
  bootstrap: [ AppComponent ]
})

Then call in your component:

import { CookieService } from 'ngx-cookie-service';

constructor( private cookieService: CookieService ) { }

ngOnInit(): void {
  this.cookieService.set( 'name', 'Test Cookie' ); // To Set Cookie
  this.cookieValue = this.cookieService.get('name'); // To Get Cookie
}

That's it!

Get element of JS object with an index

If you want a specific order, then you must use an array, not an object. Objects do not have a defined order.

For example, using an array, you could do this:

var myobj = [{"A":["B"]}, {"B": ["C"]}];
var firstItem = myobj[0];

Then, you can use myobj[0] to get the first object in the array.

Or, depending upon what you're trying to do:

var myobj = [{key: "A", val:["B"]}, {key: "B",  val:["C"]}];
var firstKey = myobj[0].key;   // "A"
var firstValue = myobj[0].val; // "["B"]

Merge development branch with master

1. //push the latest changes of current development branch if any        
git push (current development branch)

2. //switch to master branch
git checkout master 

3. //pull all the changes if any from (current development branch)
git pull origin (current development branch)

4. //Now merge development into master    
git merge development

5. //push the master branch
git push origin master

Error
To https://github.com/rajputankit22/todos-posts.git
 ! [rejected]        master -> master (fetch first)
error: failed to push some refs to 'https://github.com/rajputankit22/todos-posts.git'
hint: Updates were rejected because the remote contains work that you do
hint: not have locally. This is usually caused by another repository pushing
hint: to the same ref. You may want to first integrate the remote changes
hint: (e.g., 'git pull ...') before pushing again.
hint: See the 'Note about fast-forwards' in 'git push --help' for details.

Then Use 
5. //push the master branch forcefully
git push -f origin master

Reading in from System.in - Java

Well, you may read System.in itself as it is a valid InputStream. Or also you can wrap it in a BufferedReader:

BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

How to subscribe to an event on a service in Angular2?

Using alpha 28, I accomplished programmatically subscribing to event emitters by way of the eventEmitter.toRx().subscribe(..) method. As it is not intuitive, it may perhaps change in a future release.

how to get data from selected row from datagridview

I was having the same issue and this works excellently.

Private Sub DataGridView17_CellFormatting(sender As Object, e As System.Windows.Forms.DataGridViewCellFormattingEventArgs) Handles DataGridView17.CellFormatting  
  'Display complete contents in tooltip even though column display cuts off part of it.   
  DataGridView17.Rows(e.RowIndex).Cells(e.ColumnIndex).ToolTipText = DataGridView17.Rows(e.RowIndex).Cells(e.ColumnIndex).Value 
End Sub

How do I get a HttpServletRequest in my spring beans?

If FlexContext is not available:

Solution 1: inside method (>= Spring 2.0 required)

HttpServletRequest request = 
        ((ServletRequestAttributes)RequestContextHolder.getRequestAttributes())
                .getRequest();

Solution 2: inside bean (supported by >= 2.5, Spring 3.0 for singelton beans required!)

@Autowired
private HttpServletRequest request;

how to compare two elements in jquery

You could compare DOM elements. Remember that jQuery selectors return arrays which will never be equal in the sense of reference equality.

Assuming:

<div id="a" class="a"></div>

this:

$('div.a')[0] == $('div#a')[0]

returns true.

JDBC ODBC Driver Connection

Didn't work with ODBC-Bridge for me too. I got the way around to initialize ODBC connection using ODBC driver.

 import java.sql.*;  
 public class UserLogin
 {
     public static void main(String[] args)
     {
        try
        {    
            Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");

            // C:\\databaseFileName.accdb" - location of your database 
           String url = "jdbc:odbc:Driver={Microsoft Access Driver (*.mdb, *.accdb)};DBQ=" + "C:\\emp.accdb";

            // specify url, username, pasword - make sure these are valid 
            Connection conn = DriverManager.getConnection(url, "username", "password");

            System.out.println("Connection Succesfull");
         } 
         catch (Exception e) 
         {
            System.err.println("Got an exception! ");
            System.err.println(e.getMessage());

          }
      }
  }

PHP prepend leading zero before single digit number, on-the-fly

You can use sprintf: http://php.net/manual/en/function.sprintf.php

<?php
$num = 4;
$num_padded = sprintf("%02d", $num);
echo $num_padded; // returns 04
?>

It will only add the zero if it's less than the required number of characters.

Edit: As pointed out by @FelipeAls:

When working with numbers, you should use %d (rather than %s), especially when there is the potential for negative numbers. If you're only using positive numbers, either option works fine.

For example:

sprintf("%04s", 10); returns 0010
sprintf("%04s", -10); returns 0-10

Where as:

sprintf("%04d", 10); returns 0010
sprintf("%04d", -10); returns -010

How to Apply Mask to Image in OpenCV?

Well, this question appears on top of search results, so I believe we need code example here. Here's the Python code:

import cv2

def apply_mask(frame, mask):
    """Apply binary mask to frame, return in-place masked image."""
    return cv2.bitwise_and(frame, frame, mask=mask)

Mask and frame must be the same size, so pixels remain as-is where mask is 1 and are set to zero where mask pixel is 0.

And for C++ it's a little bit different:

cv::Mat inFrame; // Original (non-empty) image
cv::Mat mask; // Original (non-empty) mask

// ...

cv::Mat outFrame;  // Result output
inFrame.copyTo(outFrame, mask);

Press TAB and then ENTER key in Selenium WebDriver

Using Java:

private WebDriver driver = new FirefoxDriver();
WebElement element = driver.findElement(By.id("<ElementID>"));//Enter ID for the element. You can use Name, xpath, cssSelector whatever you like
element.sendKeys(Keys.TAB);
element.sendKeys(Keys.ENTER);

Using C#:

private IWebDriver driver = new FirefoxDriver();
IWebElement element = driver.FindElement(By.Name("q"));
element.SendKeys(Keys.Tab);
element.SendKeys(Keys.Enter);

Meaning of ${project.basedir} in pom.xml

There are a set of available properties to all Maven projects.

From Introduction to the POM:

project.basedir: The directory that the current project resides in.

This means this points to where your Maven projects resides on your system. It corresponds to the location of the pom.xml file. If your POM is located inside /path/to/project/pom.xml then this property will evaluate to /path/to/project.

Some properties are also inherited from the Super POM, which is the case for project.build.directory. It is the value inside the <project><build><directory> element of the POM. You can get a description of all those values by looking at the Maven model. For project.build.directory, it is:

The directory where all files generated by the build are placed. The default value is target.

This is the directory that will hold every generated file by the build.

How to create a TextArea in Android

Use TextView inside a ScrollView

<ScrollView
    android:id="@+id/ScrollView01"
    android:layout_width="wrap_content"
    android:layout_height="150dip">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"/>

</ScrollView>

Masking password input from the console : Java

The given code given will work absolutely fine if we run from console. and there is no package name in the class

You have to make sure where you have your ".class" file. because, if package name is given for the class, you have to make sure to keep the ".class" file inside the specified folder. For example, my package name is "src.main.code" , I have to create a code folder,inside main folder, inside src folder and put Test.class in code folder. then it will work perfectly.

Scrolling to element using webdriver?

You are trying to run Java code with Python. In Python/Selenium, the org.openqa.selenium.interactions.Actions are reflected in ActionChains class:

from selenium.webdriver.common.action_chains import ActionChains

element = driver.find_element_by_id("my-id")

actions = ActionChains(driver)
actions.move_to_element(element).perform()

Or, you can also "scroll into view" via scrollIntoView():

driver.execute_script("arguments[0].scrollIntoView();", element)

If you are interested in the differences:

Character reading from file in Python

Actually, U+2018 is the Unicode representation of the special character ‘ . If you want, you can convert instances of that character to U+0027 with this code:

text = text.replace (u"\u2018", "'")

In addition, what are you using to write the file? f1.read() should return a string that looks like this:

'I don\xe2\x80\x98t like this'

If it's returning this string, the file is being written incorrectly:

'I don\u2018t like this'

Call asynchronous method in constructor?

You could try AsyncMVVM.

Page2.xaml:

<PhoneApplicationPage x:Class="Page2"
                      xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation">
    <ListView ItemsSource="{Binding Writings}" />
</PhoneApplicationPage>

Page2.xaml.cs:

public partial class Page2
{
    InitializeComponent();
    DataContext = new ViewModel2();
}

ViewModel2.cs:

public class ViewModel2: AsyncBindableBase
{
    public IEnumerable<Writing> Writings
    {
        get { return Property.Get(GetWritingsAsync); }
    }

    private async Task<IEnumerable<Writing>> GetWritingsAsync()
    {
        string jsonData = await JsonDataManager.GetJsonAsync("1");
        JObject obj = JObject.Parse(jsonData);
        JArray array = (JArray)obj["posts"];

        for (int i = 0; i < array.Count; i++)
        {
            Writing writing = new Writing();
            writing.content = JsonDataManager.JsonParse(array, i, "content");
            writing.date = JsonDataManager.JsonParse(array, i, "date");
            writing.image = JsonDataManager.JsonParse(array, i, "url");
            writing.summary = JsonDataManager.JsonParse(array, i, "excerpt");
            writing.title = JsonDataManager.JsonParse(array, i, "title");
            yield return writing;
        }
    }
}

Visual Studio: How to break on handled exceptions?

A technique I use is something like the following. Define a global variable that you can use for one or multiple try catch blocks depending on what you're trying to debug and use the following structure:

if(!GlobalTestingBool)
{
   try
   {
      SomeErrorProneMethod();
   }
   catch (...)
   {
      // ... Error handling ...
   }
}
else
{
   SomeErrorProneMethod();
}

I find this gives me a bit more flexibility in terms of testing because there are still some exceptions I don't want the IDE to break on.

How can I send JSON response in symfony2 controller

Symfony 2.1

$response = new Response(json_encode(array('name' => $name)));
$response->headers->set('Content-Type', 'application/json');

return $response;

Symfony 2.2 and higher

You have special JsonResponse class, which serialises array to JSON:

return new JsonResponse(array('name' => $name));

But if your problem is How to serialize entity then you should have a look at JMSSerializerBundle

Assuming that you have it installed, you'll have simply to do

$serializedEntity = $this->container->get('serializer')->serialize($entity, 'json');

return new Response($serializedEntity);

You should also check for similar problems on StackOverflow:

Printing chars and their ASCII-code in C

This prints out all ASCII values:

int main()
{
    int i;
    i=0;
    do
    {
        printf("%d %c \n",i,i);
        i++;
    }
    while(i<=255);
    return 0;
}

and this prints out the ASCII value for a given character:

int main()
{
    int e;
    char ch;
    clrscr();
    printf("\n Enter a character : ");
    scanf("%c",&ch);
    e=ch;
    printf("\n The ASCII value of the character is : %d",e);
    getch();
    return 0;
}

Create mysql table directly from CSV file using the CSV Storage engine?

I just discovered csvkit, which is a set of Unix command-line tools for CSV files. I installed it on my Mac with pip install csvkit. The command was:

csvsql --dialect mysql --snifflimit 100000 bigdatafile.csv > maketable.sql

You can alternatively provide a DB connection string and it can load the table directly.

How to remove an element from an array in Swift

I use this extension, almost same as Varun's, but this one (below) is all-purpose:

 extension Array where Element: Equatable  {
        mutating func delete(element: Iterator.Element) {
                self = self.filter{$0 != element }
        }
    }

How can I lookup a Java enum from its String value?

You're close. For arbitrary values, try something like the following:

public enum Day { 

    MONDAY("M"), TUESDAY("T"), WEDNESDAY("W"),
    THURSDAY("R"), FRIDAY("F"), SATURDAY("Sa"), SUNDAY("Su"), ;

    private final String abbreviation;

    // Reverse-lookup map for getting a day from an abbreviation
    private static final Map<String, Day> lookup = new HashMap<String, Day>();

    static {
        for (Day d : Day.values()) {
            lookup.put(d.getAbbreviation(), d);
        }
    }

    private Day(String abbreviation) {
        this.abbreviation = abbreviation;
    }

    public String getAbbreviation() {
        return abbreviation;
    }

    public static Day get(String abbreviation) {
        return lookup.get(abbreviation);
    }
}

How to use OR condition in a JavaScript IF statement?

More then one condition statement is needed to use OR(||) operator in if conditions and notation is ||.

if(condition || condition){ 
   some stuff
}

What is the difference between README and README.md in GitHub projects?

README.md or .mkdn or .markdown denotes that the file is markdown formatted. Markdown is a markup language. With it you can easily display headers or have italic words, or bold or almost anything that can be done to text

How to find foreign key dependencies in SQL Server?

try: sp_help [table_name]

you will get all information about table, including all foreign keys

onchange event on input type=range is not triggering in firefox while dragging

Andrew Willem's solutions are not mobile device compatible.

Here's a modification of his second solution that works in Edge, IE, Opera, FF, Chrome, iOS Safari and mobile equivalents (that I could test):

Update 1: Removed "requestAnimationFrame" portion, as I agree it's not necessary:

var listener = function() {
  // do whatever
};

slider1.addEventListener("input", function() {
  listener();
  slider1.addEventListener("change", listener);
});
slider1.addEventListener("change", function() {
  listener();
  slider1.removeEventListener("input", listener);
}); 

Update 2: Response to Andrew's 2nd Jun 2016 updated answer:

Thanks, Andrew - that appears to work in every browser I could find (Win desktop: IE, Chrome, Opera, FF; Android Chrome, Opera and FF, iOS Safari).

Update 3: if ("oninput in slider) solution

The following appears to work across all the above browsers. (I cannot find the original source now.) I was using this, but it subsequently failed on IE and so I went looking for a different one, hence I ended up here.

if ("oninput" in slider1) {
    slider1.addEventListener("input", function () {
        // do whatever;
    }, false);
}

But before I checked your solution, I noticed this was working again in IE - perhaps there was some other conflict.

Disable time in bootstrap date time picker

 $("#datetimepicker4").datepicker({
    dateFormat: 'mm/dd/yy',
    changeMonth: true,
    changeYear: true,
    showOtherMonths: true,
    selectOtherMonths: true,
    pickTime: false,
    format: 'YYYY-MM-DD'
});

how to pass this element to javascript onclick function and add a class to that clicked element

You have two issues in your code.. First you need reference to capture the element on click. Try adding another parameter to your function to reference this. Also active class is for li element initially while you are tryin to add it to "a" element in the function. try this..

<div class="row" style="padding-left:21px;">
 <ul class="nav nav-tabs" style="padding-left:40px;">
      <li class="active filter"><a href="#month" onclick="Data('month',this)">This Month</a></li>
      <li class="filter"><a href="#year" onclick="Data('year',this)">Year</a></li>
      <li class="filter"><a href="#last60"  onclick="Data('last60',this)">60 Days</a></li>
      <li class="filter"><a href="#last90"  onclick="Data('last90',this)">90 Days</a></li>
    </ul> 

</div>

<script>
  function Data(string,element)
    { 
      //1. get some data from server according to month year etc.,
      //2. unactive all the remaining li's and make the current clicked element active by adding "active" class to the element
      $('.filter').removeClass('active');

      $(element).parent().addClass('active') ;

    } 
</script>

Nullable types: better way to check for null or zero in c#

Using generics:

static bool IsNullOrDefault<T>(T value)
{
    return object.Equals(value, default(T));
}

//...
double d = 0;
IsNullOrDefault(d); // true
MyClass c = null;
IsNullOrDefault(c); // true

If T it's a reference type, value will be compared with null ( default(T) ), otherwise, if T is a value type, let's say double, default(t) is 0d, for bool is false, for char is '\0' and so on...

SQL Query for Selecting Multiple Records

I have 3 fields to fetch from Oracle Database,Which is for Forex and Currency Application.

SELECT BUY.RATE FROM FRBU.CURRENCY WHERE CURRENCY.MARKET =10 AND CURRENCY.CODE IN (‘USD’, ’AUD’, ‘SGD’)

How to get rid of underline for Link component of React Router?

There's also another way to properly remove the styling of the link. You have to give it style of textDecoration='inherit' and color='inherit' you can either add those as styling to the link tag like:

<Link style={{ color: 'inherit', textDecoration: 'inherit'}}>

or to make it more general just create a css class like:

.text-link {
    color: inherit;
    text-decoration: inherit;
}

And then just <Link className='text-link'>

MVC 4 Data Annotations "Display" Attribute

Also internationalization.

I fooled around with this some a while back. Did this in my model:

[Display(Name = "XXX", ResourceType = typeof(Labels))]

I had a separate class library for all the resources, so I had Labels.resx, Labels.culture.resx, etc.

In there I had key = XXX, value = "meaningful string in that culture."

How to pause javascript code execution for 2 seconds

Javascript is single-threaded, so by nature there should not be a sleep function because sleeping will block the thread. setTimeout is a way to get around this by posting an event to the queue to be executed later without blocking the thread. But if you want a true sleep function, you can write something like this:

function sleep(miliseconds) {
   var currentTime = new Date().getTime();

   while (currentTime + miliseconds >= new Date().getTime()) {
   }
}

Note: The above code is NOT recommended.

How to increase MySQL connections(max_connections)?

If you need to increase MySQL Connections without MySQL restart do like below

mysql> show variables like 'max_connections';
+-----------------+-------+
| Variable_name   | Value |
+-----------------+-------+
| max_connections | 100   |
+-----------------+-------+
1 row in set (0.00 sec)

mysql> SET GLOBAL max_connections = 150;
Query OK, 0 rows affected (0.00 sec)

mysql> show variables like 'max_connections';
+-----------------+-------+
| Variable_name   | Value |
+-----------------+-------+
| max_connections | 150   |
+-----------------+-------+
1 row in set (0.00 sec)

These settings will change at MySQL Restart.


For permanent changes add below line in my.cnf and restart MySQL

max_connections = 150

How can I convert an HTML element to a canvas element?

No such thing, sorry.

Though the spec states:

A future version of the 2D context API may provide a way to render fragments of documents, rendered using CSS, straight to the canvas.

Which may be as close as you'll get.

A lot of people want a ctx.drawArbitraryHTML/Element kind of deal but there's nothing built in like that.

The only exception is Mozilla's exclusive drawWindow, which draws a snapshot of the contents of a DOM window into the canvas. This feature is only available for code running with Chrome ("local only") privileges. It is not allowed in normal HTML pages. So you can use it for writing FireFox extensions like this one does but that's it.

Angular 2 Date Input not binding to date value

Angular 2 , 4 and 5 :

the simplest way : plunker

<input type="date" [ngModel] ="dt | date:'yyyy-MM-dd'" (ngModelChange)="dt = $event">

How can I connect to Android with ADB over TCP?

To switch between TCP and USB modes with just one command, you can add this to /init.rc:

on property:service.adb.tcp.port=*
    restart adbd

on property:service.adb.tcp.enable=1
    setprop service.adb.tcp.port 5555

on property:service.adb.tcp.enable=0
    setprop service.adb.tcp.port -1

And now you can use property service.adb.tcp.enable to enable or disable listening on port 5555. Run netstat to check whether it's listening. As you can see it will also trigger if you do wish to change service.adb.tcp.port manually.

ASP.NET Core form POST results in a HTTP 415 Unsupported Media Type response

the problem can because of MVC MW.you must set formatterType in MVC options:

services.AddMvc(options =>
            {
                options.UseCustomStringModelBinder();
                options.AllowEmptyInputInBodyModelBinding = true;
                foreach (var formatter in options.InputFormatters)
                {
                    if (formatter.GetType() == typeof(SystemTextJsonInputFormatter))
                        ((SystemTextJsonInputFormatter)formatter).SupportedMediaTypes.Add(
                            Microsoft.Net.Http.Headers.MediaTypeHeaderValue.Parse("text/plain"));
                }
            }).AddJsonOptions(options =>
            {
                options.JsonSerializerOptions.PropertyNameCaseInsensitive = true;
            });

How do I loop through rows with a data reader in C#?

while (dr.Read())
{
    for (int i = 0; i < dr.FieldCount; i++)
    {
        subjob.Items.Add(dr[i]);
    }
}

to read rows in one colunmn

How to get the current TimeStamp?

In Qt 4.7, there is the QDateTime::currentMSecsSinceEpoch() static function, which does exactly what you need, without any intermediary steps. Hence I'd recommend that for projects using Qt 4.7 or newer.

Plot data in descending order as appears in data frame

You want reorder(). Here is an example with dummy data

set.seed(42)
df <- data.frame(Category = sample(LETTERS), Count = rpois(26, 6))

require("ggplot2")

p1 <- ggplot(df, aes(x = Category, y = Count)) +
         geom_bar(stat = "identity")

p2 <- ggplot(df, aes(x = reorder(Category, -Count), y = Count)) +
         geom_bar(stat = "identity")

require("gridExtra")
grid.arrange(arrangeGrob(p1, p2))

Giving:

enter image description here

Use reorder(Category, Count) to have Category ordered from low-high.

how to upload a file to my server using html

<form id="uploadbanner" enctype="multipart/form-data" method="post" action="#">
   <input id="fileupload" name="myfile" type="file" />
   <input type="submit" value="submit" id="submit" />
</form>

To upload a file, it is essential to set enctype="multipart/form-data" on your form

You need that form type and then some php to process the file :)

You should probably check out Uploadify if you want something very customisable out of the box.

What is the difference between ExecuteScalar, ExecuteReader and ExecuteNonQuery?

ExecuteNonQuery: is typically used when there is nothing returned from the Sql statements like insert ,update, delete operations.

cmd.ExcecuteNonQuery();

ExecuteScalar:

It will be used when Sql query returns single value.

Int b = cmd.ExcecuteScalar();

ExecuteReader

It will be used when Sql query or Stored Procedure returns multiple rows/columns

SqlDataReader dr = cmd.ExecuteReader();

for more information you can click here http://www.dotnetqueries.com/Article/148/-difference-between-executescalar-executereader-executenonquery

Add 10 seconds to a Date

const timeObject = new Date(); 
timeObject = new Date(timeObject.getTime() + 1000 * 10);
console.log(timeObject);

Also please refer: How to add 30 minutes to a JavaScript Date object?

How to set HTTP headers (for cache-control)?

For Apache server, you should check mod_expires for setting Expires and Cache-Control headers.

Alternatively, you can use Header directive to add Cache-Control on your own:

Header set Cache-Control "max-age=290304000, public"

java.net.MalformedURLException: no protocol

Try instead of db.parse(xml):

Document doc = db.parse(new InputSource(new StringReader(**xml**)));

Android view pager with page indicator

UPDATE: 22/03/2017

main fragment layout:

       <FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
            xmlns:app="http://schemas.android.com/apk/res-auto"
            android:layout_width="match_parent"
            android:layout_height="match_parent">

            <android.support.v4.view.ViewPager
                android:id="@+id/viewpager"
                android:layout_width="match_parent"
                android:layout_height="match_parent" />

            <RadioGroup
                android:id="@+id/page_group"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_gravity="center_horizontal|bottom"
                android:layout_marginBottom="@dimen/margin_help_container"
                android:orientation="horizontal">

                <RadioButton
                    android:id="@+id/page1"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:checked="true" />

                <RadioButton
                    android:id="@+id/page2"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content" />

                <RadioButton
                    android:id="@+id/page3"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content" />
            </RadioGroup>
        </FrameLayout>

set up view and event on your fragment like this:

        mViewPaper = (ViewPager) view.findViewById(R.id.viewpager);
        mViewPaper.setAdapter(adapder);

        mPageGroup = (RadioGroup) view.findViewById(R.id.page_group);
        mPageGroup.setOnCheckedChangeListener(this);

        mViewPaper.addOnPageChangeListener(this);

       *************************************************
       *************************************************

    @Override
    public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
    }

    @Override
    public void onPageSelected(int position) {
        // when current page change -> update radio button state
        int radioButtonId = mPageGroup.getChildAt(position).getId();
        mPageGroup.check(radioButtonId);
    }

    @Override
    public void onPageScrollStateChanged(int state) {
    }

    @Override
    public void onCheckedChanged(RadioGroup radioGroup, int checkedId) {
        // when checked radio button -> update current page
        RadioButton checkedRadioButton = (RadioButton)radioGroup.findViewById(checkedId);
        // get index of checked radio button
        int index = radioGroup.indexOfChild(checkedRadioButton);

        // update current page
        mViewPaper.setCurrentItem(index), true);
    }

custom checkbox state: Custom checkbox image android

Viewpager tutorial: http://architects.dzone.com/articles/android-tutorial-using

enter image description here

Jquery submit form

Use the following jquery to submit a selectbox with out a submit button. Use "change" instead of click as shown above.

$("selectbox").change(function() { 
   document.forms["form"].submit();
});

Cheers!

PHP - syntax error, unexpected T_CONSTANT_ENCAPSED_STRING

When you're working with strings in PHP you'll need to pay special attention to the formation, using " or '

$string = 'Hello, world!';
$string = "Hello, world!";

Both of these are valid, the following is not:

$string = "Hello, world';

You must also note that ' inside of a literal started with " will not end the string, and vice versa. So when you have a string which contains ', it is generally best practice to use double quotation marks.

$string = "It's ok here";

Escaping the string is also an option

$string = 'It\'s ok here too';

More information on this can be found within the documentation

Add space between <li> elements

Since you are asking for space between , I would add an override to the last item to get rid of the extra margin there:

_x000D_
_x000D_
li {_x000D_
  background: red;_x000D_
  margin-bottom: 40px;_x000D_
}_x000D_
_x000D_
li:last-child {_x000D_
 margin-bottom: 0px;_x000D_
}_x000D_
_x000D_
ul {_x000D_
  background: silver;_x000D_
  padding: 1px;  _x000D_
  padding-left: 40px;_x000D_
}
_x000D_
<ul>_x000D_
<li>Item 1</li>_x000D_
<li>Item 1</li>_x000D_
<li>Item 1</li>_x000D_
<li>Item 1</li>_x000D_
<li>Item 1</li>_x000D_
</ul>
_x000D_
_x000D_
_x000D_

The result of it might not be visual at all times, because of margin-collapsing and stuff... in the example snippets I've included, I've added a small 1px padding to the ul-element to prevent the collapsing. Try removing the li:last-child-rule, and you'll see that the last item now extends the size of the ul-element.

Split string in Lua?

I used the above examples to craft my own function. But the missing piece for me was automatically escaping magic characters.

Here is my contribution:

function split(text, delim)
    -- returns an array of fields based on text and delimiter (one character only)
    local result = {}
    local magic = "().%+-*?[]^$"

    if delim == nil then
        delim = "%s"
    elseif string.find(delim, magic, 1, true) then
        -- escape magic
        delim = "%"..delim
    end

    local pattern = "[^"..delim.."]+"
    for w in string.gmatch(text, pattern) do
        table.insert(result, w)
    end
    return result
end

How to bind bootstrap popover on dynamic elements

I did this and it works for me. "content" is placesContent object. not the html content!

var placesContent = $('#placescontent');
$('#places').popover({
        trigger: "click",
        placement: "bottom",
        container: 'body',
        html : true,
        content : placesContent,
    });

$('#places').on('shown.bs.popover', function(){
  $('#addPlaceBtn').on('click', addPlace);
}

<div id="placescontent"><div id="addPlaceBtn">Add</div></div>

python xlrd unsupported format, or corrupt file.

I meet the same problem.

it lies in the .xls file itself - it looks like an Excel file however it isn't. (see if there's a pop up when you plainly open the .xls from Excel)

sjmachin commented on Jan 19, 2013 from https://github.com/python-excel/xlrd/issues/26 helps.

Finish all activities at a time

in LoginActivity

@Override
    public void onBackPressed() {
        Intent startMain = new Intent(Intent.ACTION_MAIN);
        startMain.addCategory(Intent.CATEGORY_HOME);
        startMain.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
        startActivity(startMain);
        finish();
        super.onBackPressed();
    }

fatal error C1083: Cannot open include file: 'xyz.h': No such file or directory?

Add the "code" folder to the project properties within Visual Studio

Project->Properties->Configuration Properties->C/C++->Additional Include Directories

move a virtual machine from one vCenter to another vCenter

For moving a virtual machine you need not clone the VM, just copy the VM files (after powering the VM off) to external HDD and register the same on destination host.

How to force Chrome browser to reload .css file while debugging in Visual Studio?

If you are using SiteGround as your hosting company and none of the other solutions have worked, try this:

From the cPanel, go to "SITE IMPROVEMENT TOOLS" and click "SuperCacher." On the following page, click the "Flush Cache" button.

How to create an Observable from static data similar to http one in Angular?

This is how you can create a simple observable for static data.

let observable = Observable.create(observer => {
  setTimeout(() => {
    let users = [
      {username:"balwant.padwal",city:"pune"},
      {username:"test",city:"mumbai"}]

    observer.next(users); // This method same as resolve() method from Angular 1
    console.log("am done");
    observer.complete();//to show we are done with our processing
    // observer.error(new Error("error message"));
  }, 2000);

})

to subscribe to it is very easy

observable.subscribe((data)=>{
  console.log(data); // users array display
});

I hope this answer is helpful. We can use HTTP call instead static data.

How to change JAVA.HOME for Eclipse/ANT

Set environment variables

This is the part that I always forget. Because you’re installing Ant by hand, you also need to deal with setting environment variables by hand.

For Windows XP: To set environment variables on Windows XP, right click on My Computer and select Properties. Then go to the Advanced tab and click the Environment Variables button at the bottom.

For Windows 7: To set environment variables on Windows 7, right click on Computer and select Properties. Click on Advanced System Settings and click the Environment Variables button at the bottom.

The dialog for both Windows XP and Windows 7 is the same. Make sure you’re only working on system variables and not user variables.

The only environment variable that you absolutely need is JAVA_HOME, which tells Ant the location of your JRE. If you’ve installed the JDK, this is likely c:\Program Files\Java\jdk1.x.x\jre on Windows XP and c:\Program Files(x86)\Java\jdk1.x.x\jre on Windows 7. You’ll note that both have spaces in their paths, which causes a problem. You need to use the mangled name[3] instead of the complete name. So for Windows XP, use C:\Progra~1\Java\jdk1.x.x\jre and for Windows 7, use C:\Progra~2\Java\jdk1.6.0_26\jre if it’s installed in the Program Files(x86) folder (otherwise use the same as Windows XP).

That alone is enough to get Ant to work, but for convenience, it’s a good idea to add the Ant binary path to the PATH variable. This variable is a semicolon-delimited list of directories to search for executables. To be able to run ant in any directory, Windows needs to know both the location for the ant binary and for the java binary. You’ll need to add both of these to the end of the PATH variable. For Windows XP, you’ll likely add something like this:

;c:\java\ant\bin;C:\Progra~1\Java\jdk1.x.x\jre\bin

For Windows 7, it will look something like this:

;c:\java\ant\bin;C:\Progra~2\Java\jdk1.x.x\jre\bin

Done

Once you’ve done that and applied the changes, you’ll need to open a new command prompt to see if the variables are set properly. You should be able to simply run ant and see something like this:

Buildfile: build.xml does not exist!
Build failed

How to determine if Javascript array contains an object with an attribute that equals a given value?

var without2 = (arr, args) => arr.filter(v => v.id !== args.id); Example:

without2([{id:1},{id:1},{id:2}],{id:2})

Result: without2([{id:1},{id:1},{id:2}],{id:2})

How to change the background color of Action Bar's Option Menu in Android 4.2?

Following are the changes required in your theme for changing action bar & overflow menu background color. You need to configure "android:background" of actionBarStyle & popupMenuStyle

<application
            android:name="...."
            android:theme="@style/AppLightTheme">

<style name="AppLightTheme" parent="android:Theme.Holo.Light">      
        <item name="android:actionBarStyle">@style/ActionBarLight</item>
        <item name="android:popupMenuStyle">@style/ListPopupWindowLight</item>
</style>

<style name="ActionBarLight" parent="android:style/Widget.Holo.Light.ActionBar">
        <item name="android:background">@color/white</item>
</style>


<style name="ListPopupWindowLight"parent="@android:style/Widget.Holo.Light.ListPopupWindow">
        <item name="android:background">@color/white</item>
</style>

What is the difference between `sorted(list)` vs `list.sort()`?

What is the difference between sorted(list) vs list.sort()?

  • list.sort mutates the list in-place & returns None
  • sorted takes any iterable & returns a new list, sorted.

sorted is equivalent to this Python implementation, but the CPython builtin function should run measurably faster as it is written in C:

def sorted(iterable, key=None):
    new_list = list(iterable)    # make a new list
    new_list.sort(key=key)       # sort it
    return new_list              # return it

when to use which?

  • Use list.sort when you do not wish to retain the original sort order (Thus you will be able to reuse the list in-place in memory.) and when you are the sole owner of the list (if the list is shared by other code and you mutate it, you could introduce bugs where that list is used.)
  • Use sorted when you want to retain the original sort order or when you wish to create a new list that only your local code owns.

Can a list's original positions be retrieved after list.sort()?

No - unless you made a copy yourself, that information is lost because the sort is done in-place.

"And which is faster? And how much faster?"

To illustrate the penalty of creating a new list, use the timeit module, here's our setup:

import timeit
setup = """
import random
lists = [list(range(10000)) for _ in range(1000)]  # list of lists
for l in lists:
    random.shuffle(l) # shuffle each list
shuffled_iter = iter(lists) # wrap as iterator so next() yields one at a time
"""

And here's our results for a list of randomly arranged 10000 integers, as we can see here, we've disproven an older list creation expense myth:

Python 2.7

>>> timeit.repeat("next(shuffled_iter).sort()", setup=setup, number = 1000)
[3.75168503401801, 3.7473005310166627, 3.753129180986434]
>>> timeit.repeat("sorted(next(shuffled_iter))", setup=setup, number = 1000)
[3.702025591977872, 3.709248117986135, 3.71071034099441]

Python 3

>>> timeit.repeat("next(shuffled_iter).sort()", setup=setup, number = 1000)
[2.797430992126465, 2.796825885772705, 2.7744789123535156]
>>> timeit.repeat("sorted(next(shuffled_iter))", setup=setup, number = 1000)
[2.675589084625244, 2.8019039630889893, 2.849375009536743]

After some feedback, I decided another test would be desirable with different characteristics. Here I provide the same randomly ordered list of 100,000 in length for each iteration 1,000 times.

import timeit
setup = """
import random
random.seed(0)
lst = list(range(100000))
random.shuffle(lst)
"""

I interpret this larger sort's difference coming from the copying mentioned by Martijn, but it does not dominate to the point stated in the older more popular answer here, here the increase in time is only about 10%

>>> timeit.repeat("lst[:].sort()", setup=setup, number = 10000)
[572.919036605, 573.1384446719999, 568.5923951]
>>> timeit.repeat("sorted(lst[:])", setup=setup, number = 10000)
[647.0584738299999, 653.4040515829997, 657.9457361929999]

I also ran the above on a much smaller sort, and saw that the new sorted copy version still takes about 2% longer running time on a sort of 1000 length.

Poke ran his own code as well, here's the code:

setup = '''
import random
random.seed(12122353453462456)
lst = list(range({length}))
random.shuffle(lst)
lists = [lst[:] for _ in range({repeats})]
it = iter(lists)
'''
t1 = 'l = next(it); l.sort()'
t2 = 'l = next(it); sorted(l)'
length = 10 ** 7
repeats = 10 ** 2
print(length, repeats)
for t in t1, t2:
    print(t)
    print(timeit(t, setup=setup.format(length=length, repeats=repeats), number=repeats))

He found for 1000000 length sort, (ran 100 times) a similar result, but only about a 5% increase in time, here's the output:

10000000 100
l = next(it); l.sort()
610.5015971539542
l = next(it); sorted(l)
646.7786222379655

Conclusion:

A large sized list being sorted with sorted making a copy will likely dominate differences, but the sorting itself dominates the operation, and organizing your code around these differences would be premature optimization. I would use sorted when I need a new sorted list of the data, and I would use list.sort when I need to sort a list in-place, and let that determine my usage.

Are HTTP headers case-sensitive?

The RFC for HTTP (as cited above) dictates that the headers are case-insensitive, however you will find that with certain browsers (I'm looking at you, IE) that capitalizing each of the words tends to be best:

Location: http://stackoverflow.com

Content-Type: text/plain

vs

location: http://stackoverflow.com

content-type: text/plain

This isn't "HTTP" standard, but just another one of the browser quirks, we as developers, have to think about.

Exit single-user mode

To switch out of Single User mode, try:

ALTER DATABASE [my_db] SET MULTI_USER

To switch back to Single User mode, you can use:

ALTER DATABASE [my_db] SET SINGLE_USER

ReactJS: "Uncaught SyntaxError: Unexpected token <"

In addition to Dee Jee solution, After trying out his solution, My error never went.

I noticed(after two days of head scratch) that the browser has cached the files improperly.

  • My browser wasn't able to load the preview of the cached files and status code from express was 301.
  • In the networks tab of the browser dev tools, I get that those files are server from disk cache.

Solution

Remove the cached files. By clearing the browser history in a span of 1 hour, so that all the cached files get deleted.

javax vs java package

I think it's a historical thing - if a package is introduced as an addition to an existing JRE, it comes in as javax. If it's first introduced as part of a JRE (like NIO was, I believe) then it comes in as java. Not sure why the new date and time API will end up as javax following this logic though... unless it will also be available separately as a library to work with earlier versions (which would be useful). Note from many years later: it actually ended up being in java after all.

I believe there are restrictions on the java package - I think classloaders are set up to only allow classes within java.* to be loaded from rt.jar or something similar. (There's certainly a check in ClassLoader.preDefineClass.)

EDIT: While an official explanation (the search orbfish suggested didn't yield one in the first page or so) is no doubt about "core" vs "extension", I still suspect that in many cases the decision for any particular package has an historical reason behind it too. Is java.beans really that "core" to Java, for example?

How to change python version in anaconda spyder

You can launch the correct version of Spyder by launching from Ananconda's Navigator. From the dropdown, switch to your desired environment and then press the launch Spyder button. You should be able to check the results right away.

Are HTTPS URLs encrypted?

Additionally, if you're building a ReSTful API, browser leakage and http referer issues are mostly mitigated as the client may not be a browser and you may not have people clicking links.

If this is the case I'd recommend oAuth2 login to obtain a bearer token. In which case the only sensitive data would be the initial credentials...which should probably be in a post request anyway

javax.persistence.PersistenceException: No Persistence provider for EntityManager named customerManager

my experience tells me that missing persistence.xml,will generate the same exception too.

i caught the same error msg today when i tried to run a jar package packed by ant.

when i used jar tvf to check the content of the jar file, i realized that "ant" forgot to pack the persistnece.xml for me.

after I manually repacked the jar file ,the error msg disappered.

so i believe maybe you should try simplely putting META-INF under src directory and placing your persistence.xml there.

Setting device orientation in Swift iOS

In info.plist file , change the orientations which you want in "supported interface orientation".

In swift the way supporting files->info.plist->supporting interface orientation.

Docker is in volume in use, but there aren't any Docker containers

As long as volumes are associated with a container(either running or not), they cannot be removed.

You have to run

docker inspect <container-id>/<container-name>

on each of the running/non-running containers where this volume might have been mounted onto.

If the volume is mounted onto any one of the containers, you should see it in the Mounts section of the inspect command output. Something like this :-

"Mounts": [
            {
                "Type": "volume",
                "Name": "user1",
                "Source": "/var/lib/docker/volumes/user1/_data",
                "Destination": "/opt",
                "Driver": "local",
                "Mode": "",
                "RW": true,
                "Propagation": ""
            }
        ],

After figuring out the responsible container(s), use :-

docker rm -f container-1 container-2 ...container-n in case of running containers

docker rm container-1 container-2 ...container-n in case of non-running containers

to completely remove the containers from the host machine.

Then try removing the volume using the command :-

docker volume remove <volume-name/volume-id>

Prevent form submission on Enter key press

A react js solution

 handleChange: function(e) {
    if (e.key == 'Enter') {
      console.log('test');
    }


 <div>
    <Input type="text"
       ref = "input"
       placeholder="hiya"
       onKeyPress={this.handleChange}
    />
 </div>

A warning - comparison between signed and unsigned integer expressions

I had the exact same problem yesterday working through problem 2-3 in Accelerated C++. The key is to change all variables you will be comparing (using Boolean operators) to compatible types. In this case, that means string::size_type (or unsigned int, but since this example is using the former, I will just stick with that even though the two are technically compatible).

Notice that in their original code they did exactly this for the c counter (page 30 in Section 2.5 of the book), as you rightly pointed out.

What makes this example more complicated is that the different padding variables (padsides and padtopbottom), as well as all counters, must also be changed to string::size_type.

Getting to your example, the code that you posted would end up looking like this:

cout << "Please enter the size of the frame between top and bottom";
string::size_type padtopbottom;
cin >> padtopbottom;

cout << "Please enter size of the frame from each side you would like: ";
string::size_type padsides; 
cin >> padsides;

string::size_type c = 0; // definition of c in the program

if (r == padtopbottom + 1 && c == padsides + 1) { // where the error no longer occurs

Notice that in the previous conditional, you would get the error if you didn't initialize variable r as a string::size_type in the for loop. So you need to initialize the for loop using something like:

    for (string::size_type r=0; r!=rows; ++r)   //If r and rows are string::size_type, no error!

So, basically, once you introduce a string::size_type variable into the mix, any time you want to perform a boolean operation on that item, all operands must have a compatible type for it to compile without warnings.

Keeping it simple and how to do multiple CTE in a query

You can have multiple CTEs in one query, as well as reuse a CTE:

WITH    cte1 AS
        (
        SELECT  1 AS id
        ),
        cte2 AS
        (
        SELECT  2 AS id
        )
SELECT  *
FROM    cte1
UNION ALL
SELECT  *
FROM    cte2
UNION ALL
SELECT  *
FROM    cte1

Note, however, that SQL Server may reevaluate the CTE each time it is accessed, so if you are using values like RAND(), NEWID() etc., they may change between the CTE calls.

Why is access to the path denied?

I too faced the same problem when trying to do this after deployment at server:

dirPath = Server.MapPath(".") + "\\website\\" + strUserName;
if (!Directory.Exists(dirPath))
{
    DirectoryInfo DI = Directory.CreateDirectory(dirPath);
}
string filePath = Server.MapPath(".") + "\\Website\\default.aspx";
File.Copy(filePath, dirPath + "\\default.aspx", true);
File.SetAttributes(dirPath + "\\default.aspx", FileAttributes.Normal);

I granted permission in IIS to other group including administrator and my problem got solved.

How to add jQuery to an HTML page?

Include javascript using script tags just before your ending body tag. Preferably you will want to put it in a separate file and link to it to keep things a little more organized and easier to read. Theres a simple article here that will show you how http://www.selftaughtweb.com/how-to-include-javascript/

Binding ComboBox SelectedItem using MVVM

<!-- xaml code-->
    <Grid>
        <ComboBox Name="cmbData"    SelectedItem="{Binding SelectedstudentInfo, Mode=OneWayToSource}" HorizontalAlignment="Left" Margin="225,150,0,0" VerticalAlignment="Top" Width="120" DisplayMemberPath="name" SelectedValuePath="id" SelectedIndex="0" />
        <Button VerticalAlignment="Center" Margin="0,0,150,0" Height="40" Width="70" Click="Button_Click">OK</Button>
    </Grid>



        //student Class
        public class Student
        {
            public  int Id { set; get; }
            public string name { set; get; }
        }

        //set 2 properties in MainWindow.xaml.cs Class
        public ObservableCollection<Student> studentInfo { set; get; }
        public Student SelectedstudentInfo { set; get; }

        //MainWindow.xaml.cs Constructor
        public MainWindow()
        {
            InitializeComponent();
            bindCombo();
            this.DataContext = this;
            cmbData.ItemsSource = studentInfo;

        }

        //method to bind cobobox or you can fetch data from database in MainWindow.xaml.cs
        public void bindCombo()
        {
            ObservableCollection<Student> studentList = new ObservableCollection<Student>();
            studentList.Add(new Student { Id=0 ,name="==Select=="});
            studentList.Add(new Student { Id = 1, name = "zoyeb" });
            studentList.Add(new Student { Id = 2, name = "siddiq" });
            studentList.Add(new Student { Id = 3, name = "James" });

              studentInfo=studentList;

        }

        //button click to get selected student MainWindow.xaml.cs
        private void Button_Click(object sender, RoutedEventArgs e)
        {
            Student student = SelectedstudentInfo;
            if(student.Id ==0)
            {
                MessageBox.Show("select name from dropdown");
            }
            else
            {
                MessageBox.Show("Name :"+student.name + "Id :"+student.Id);
            }
        }

How can I apply styles to multiple classes at once?

You can have multiple CSS declarations for the same properties by separating them with commas:

.abc, .xyz {
   margin-left: 20px;
}

How to do a background for a label will be without color?

Do you want to make the label (except for the text) transparent? Windows Forms (I assume WinForms - is this true) doesn't really support transparency. The easiest way, sometimes, is Label's Backcolor to Transparent.

label1.BackColor = System.Drawing.Color.Transparent;

You will run into problems though, as WinForms really doesn't properly support transparency. Otherwise, see here:

http://www.doogal.co.uk/transparent.php

http://www.codeproject.com/KB/dotnet/transparent_controls_net.aspx

http://www.daniweb.com/code/snippet216425.html

Setting the parent of a usercontrol prevents it from being transparent

Good luck!

How to set a header in an HTTP response?

In my Controller, I merely added an HttpServletResponse parameter and manually added the headers, no filter or intercept required and it works fine:

httpServletResponse.setHeader("Access-Control-Allow-Origin", "*");
httpServletResponse.setHeader("Access-Control-Allow-Methods", "GET, OPTIONS");
httpServletResponse.setHeader("Access-Control-Allow-Headers","Origin, X-Requested-With, Content-Type, Accept, X-Auth-Token, X-Csrf-Token, WWW-Authenticate, Authorization");
httpServletResponse.setHeader("Access-Control-Allow-Credentials", "false");
httpServletResponse.setHeader("Access-Control-Max-Age", "3600");

Count indexes using "for" in Python

This?

for i in range(0,5): 
 print(i)

How to grep with a list of words

You need to use the option -f:

$ grep -f A B

The option -F does a fixed string search where as -f is for specifying a file of patterns. You may want both if the file only contains fixed strings and not regexps.

$ grep -Ff A B

You may also want the -w option for matching whole words only:

$ grep -wFf A B

Read man grep for a description of all the possible arguments and what they do.

How to draw border on just one side of a linear layout?

As an alternative (if you don't want to use background), you can easily do it by making a view as follows:

<View
    android:layout_width="2dp"
    android:layout_height="match_parent"
    android:background="#000000" />

For having a right border only, place this after the layout (where you want to have the border):

<View
    android:layout_width="2dp"
    android:layout_height="match_parent"
    android:background="#000000" />

For having a left border only, place this before the layout (where you want to have the border):

Worked for me...Hope its of some help....

ImportError: No Module Named bs4 (BeautifulSoup)

Addendum to the original query: modules.py

help('modules')

$python modules.py

It lists that module bs4 already been installed.

_codecs_kr          blinker             json                six
_codecs_tw          brotli              kaitaistruct        smtpd
_collections        bs4                 keyword             smtplib
_collections_abc    builtins            ldap3               sndhdr
_compat_pickle      bz2                 lib2to3             socket

Proper solution is:

pip install --upgrade bs4

Should solve the problem.

Not only that, it will show same error for other modules as well. So you got to issue the pip command same way as above for those errored module(s).

Add MIME mapping in web.config for IIS Express

To solve the problem, double-click the "MIME Types" configuration option while having IIS root node selected in the left panel and click "Add..." link in the Actions panel on the right. This will bring up the following dialog. Add .woff file extension and specify "application/x-font-woff" as the corresponding MIME type:

enter image description here

Follow same for woff2 with application/x-font-woff2

Login with facebook android sdk app crash API 4

The official answer from Facebook (http://developers.facebook.com/bugs/282710765082535):

Mikhail,

The facebook android sdk no longer supports android 1.5 and 1.6. Please upgrade to the next api version.

Good luck with your implementation.

How to read file contents into a variable in a batch file?

To get all the lines of the file loaded into the variable, Delayed Expansion is needed, so do the following:

SETLOCAL EnableDelayedExpansion

for /f "Tokens=* Delims=" %%x in (version.txt) do set Build=!Build!%%x

There is a problem with some special characters, though especially ;, % and !

What is the difference between statically typed and dynamically typed languages?

Statically Typed

The types are checked before run-time so mistakes can be caught earlier.

Examples = c++

Dynamically Typed

The types are checked during execution.

Examples = Python

Vue.js toggle class on click

This example is using Lists: When clicking in some li it turn red

html:

<div id="app">
  <ul>
    <li @click="activate(li.id)" :class="{ active : active_el == li.id }" v-for="li in lista">{{li.texto}}</li>   
  </ul>
</div>

JS:

var app = new Vue({
  el:"#app",
  data:{
    lista:[{"id":"1","texto":"line 1"},{"id":"2","texto":"line 2"},{"id":"3","texto":"line 3"},{"id":"4","texto":"line 4"},{"id":"5","texto":"line 5"}],
    active_el:0
  },
  methods:{
    activate:function(el){
        this.active_el = el;
    }
  }
});

css

ul > li:hover {
  cursor:pointer;
}
.active {
  color:red;
  font-weight:bold;
}

Fiddle:

https://jsfiddle.net/w37vLL68/158/

Creating a URL in the controller .NET MVC

Another way to create an absolute URL to an action:

var relativeUrl = Url.Action("MyAction");  //..or one of the other .Action() overloads
var currentUrl = Request.Url;

var absoluteUrl = new System.Uri(currentUrl, relativeUrl);

How to parse a JSON string to an array using Jackson

The other answer is correct, but for completeness, here are other ways:

List<SomeClass> list = mapper.readValue(jsonString, new TypeReference<List<SomeClass>>() { });
SomeClass[] array = mapper.readValue(jsonString, SomeClass[].class);

How do I change the background color of a plot made with ggplot2

To change the panel's background color, use the following code:

myplot + theme(panel.background = element_rect(fill = 'green', colour = 'red'))

To change the color of the plot (but not the color of the panel), you can do:

myplot + theme(plot.background = element_rect(fill = 'green', colour = 'red'))

See here for more theme details Quick reference sheet for legends, axes and themes.

How to read/process command line arguments?

I like getopt from stdlib, eg:

try:
    opts, args = getopt.getopt(sys.argv[1:], 'h', ['help'])
except getopt.GetoptError, err: 
    usage(err)

for opt, arg in opts:
    if opt in ('-h', '--help'): 
        usage()

if len(args) != 1:
    usage("specify thing...")

Lately I have been wrapping something similiar to this to make things less verbose (eg; making "-h" implicit).

How to keep Docker container running after starting services?

Motivation:

There is nothing wrong in running multiple processes inside of a docker container. If one likes to use docker as a light weight VM - so be it. Others like to split their applications into micro services. Me thinks: A LAMP stack in one container? Just great.

The answer:

Stick with a good base image like the phusion base image. There may be others. Please comment.

And this is yet just another plead for supervisor. Because the phusion base image is providing supervisor besides of some other things like cron and locale setup. Stuff you like to have setup when running such a light weight VM. For what it's worth it also provides ssh connections into the container.

The phusion image itself will just start and keep running if you issue this basic docker run statement:

moin@stretchDEV:~$ docker run -d phusion/baseimage
521e8a12f6ff844fb142d0e2587ed33cdc82b70aa64cce07ed6c0226d857b367
moin@stretchDEV:~$ docker ps
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS
521e8a12f6ff        phusion/baseimage   "/sbin/my_init"     12 seconds ago      Up 11 seconds

Or dead simple:

If a base image is not for you... For the quick CMD to keep it running I would suppose something like this for bash:

CMD exec /bin/bash -c "trap : TERM INT; sleep infinity & wait"

Or this for busybox:

CMD exec /bin/sh -c "trap : TERM INT; (while true; do sleep 1000; done) & wait"

This is nice, because it will exit immediately on a docker stop. Just plain sleep or cat will take a few seconds before the container exits.

Delay/Wait in a test case of Xcode UI testing

Additionally, you can just sleep:

sleep(10)

Since the UITests run in another process, this works. I don’t know how advisable it is, but it works.

Pandas/Python: Set value of one column based on value in another column

You can use pandas.DataFrame.mask to add virtually as many conditions as you need:

data = {'a': [1,2,3,4,5], 'b': [6,8,9,10,11]}

d = pd.DataFrame.from_dict(data, orient='columns')
c = {'c1': (2, 'Value1'), 'c2': (3, 'Value2'), 'c3': (5, d['b'])}

d['new'] = np.nan
for value in c.values():
    d['new'].mask(d['a'] == value[0], value[1], inplace=True)

d['new'] = d['new'].fillna('Else')
d

Output:

    a   b   new
0   1   6   Else
1   2   8   Value1
2   3   9   Value2
3   4   10  Else
4   5   11  11

How to get a value from a Pandas DataFrame and not the index and object type

import pandas as pd

dataset = pd.read_csv("data.csv")
values = list(x for x in dataset["column name"])

>>> values[0]
'item_0'

edit:

actually, you can just index the dataset like any old array.

import pandas as pd

dataset = pd.read_csv("data.csv")
first_value = dataset["column name"][0]

>>> print(first_value)
'item_0'

Play audio as microphone input

Just as there are printer drivers that do not connect to a printer at all but rather write to a PDF file, analogously there are virtual audio drivers available that do not connect to a physical microphone at all but can pipe input from other sources such as files or other programs.

I hope I'm not breaking any rules by recommending free/donation software, but VB-Audio Virtual Cable should let you create a pair of virtual input and output audio devices. Then you could play an MP3 into the virtual output device and then set the virtual input device as your "microphone". In theory I think that should work.

If all else fails, you could always roll your own virtual audio driver. Microsoft provides some sample code but unfortunately it is not applicable to the older Windows XP audio model. There is probably sample code available for XP too.

Convert Dictionary<string,string> to semicolon separated string in c#

Another option is to use the Aggregate extension rather than Join:

String s = myDict.Select(x => x.Key + "=" + x.Value).Aggregate((s1, s2) => s1 + ";" + s2);

Read SQL Table into C# DataTable

Here, give this a shot (this is just a pseudocode)

using System;
using System.Data;
using System.Data.SqlClient;


public class PullDataTest
{
    // your data table
    private DataTable dataTable = new DataTable();

    public PullDataTest()
    {
    }

    // your method to pull data from database to datatable   
    public void PullData()
    {
        string connString = @"your connection string here";
        string query = "select * from table";

        SqlConnection conn = new SqlConnection(connString);        
        SqlCommand cmd = new SqlCommand(query, conn);
        conn.Open();

        // create data adapter
        SqlDataAdapter da = new SqlDataAdapter(cmd);
        // this will query your database and return the result to your datatable
        da.Fill(dataTable);
        conn.Close();
        da.Dispose();
    }
}

How to get Python requests to trust a self signed SSL certificate?

Setting export SSL_CERT_FILE=/path/file.crt should do the job.

How to determine whether an object has a given property in JavaScript

Since question was regarding clunkiness of property checking, and one regular usecase for that being validation of function argument options objects, thought I'd mention a library-free short way of testing existence of multiple properties. Disclaimer: It does require ECMAScript 5 (but IMO anyone still using IE8 deserves a broken web).

function f(opts) {
  if(!["req1","req2"].every(opts.hasOwnProperty, opts)) {
      throw new Error("IllegalArgumentException");
  }
  alert("ok");
}
f({req1: 123});  // error
f({req1: 123, req2: 456});  // ok

Android M - check runtime permission - how to determine if the user checked "Never ask again"?

I found to many long and confusing answer and after reading few of the answers My conclusion is

if (!ActivityCompat.shouldShowRequestPermissionRationale(this,Manifest.permission.READ_EXTERNAL_STORAGE))
                Toast.makeText(this, "permanently denied", Toast.LENGTH_SHORT).show();

Android Fragment no view found for ID?

In my case I was trying to show a DialogFragment containing a pager and this exception was thrown when the FragmentPagerAdapter attempted to add the Fragments to the pager. Based on howettl answer I guess that it was due to the Pager parent was not the view set in setContentView() in my FragmentActivity.

The only change I did to solve the problem was to create the FragmentPagerAdapter passing in a FragmentMager obtained by calling getChildFragmentManager(), not the one obtained by calling getFragmentManager() as I normally do.

    public class PagerDialog extends DialogFragment{

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

        View rootView = inflater.inflate(R.layout.pager_dialog, container, false);

        MyPagerAdapter pagerAdapter = new MyPagerAdapter(getChildFragmentManager());
        ViewPager pager = (ViewPager) rootView.findViewById(R.id.pager);
        pager.setAdapter(pagerAdapter);

        return rootView;
    }
}

How do I load external fonts into an HTML document?

Regarding Jay Stevens answer: "The fonts available to use in an HTML file have to be present on the user's machine and accessible from the web browser, so unless you want to distribute the fonts to the user's machine via a separate external process, it can't be done." That's true.

But there is another way using javascript / canvas / flash - very good solution gives cufon: http://cufon.shoqolate.com/generate/ library that generates a very easy to use external fonts methods.

Command to list all files in a folder as well as sub-folders in windows

If you simply need to get the basic snapshot of the files + folders. Follow these baby steps:

  • Press Windows + R
  • Press Enter
  • Type cmd
  • Press Enter
  • Type dir -s
  • Press Enter

Get keys of a Typescript interface as array of strings

I had a similar problem that I had a giant list of properties that I wanted to have both an interface, and an object out of it.

NOTE: I didn't want to write (type with keyboard) the properties twice! Just DRY.


One thing to note here is, interfaces are enforced types at compile-time, while objects are mostly run-time. (Source)

As @derek mentioned in another answer, the common denominator of interface and object can be a class that serves both a type and a value.

So, TL;DR, the following piece of code should satisfy the needs:

class MyTableClass {
    // list the propeties here, ONLY WRITTEN ONCE
    id = "";
    title = "";
    isDeleted = false;
}

// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

// This is the pure interface version, to be used/exported
interface IMyTable extends MyTableClass { };

// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

// Props type as an array, to be exported
type MyTablePropsArray = Array<keyof IMyTable>;

// Props array itself!
const propsArray: MyTablePropsArray =
    Object.keys(new MyTableClass()) as MyTablePropsArray;

console.log(propsArray); // prints out  ["id", "title", "isDeleted"]


// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

// Example of creating a pure instance as an object
const tableInstance: MyTableClass = { // works properly!
    id: "3",
    title: "hi",
    isDeleted: false,
};

(Here is the above code in Typescript Playground to play more)

PS. If you don't want to assign initial values to the properties in the class, and stay with the type, you can do the constructor trick:

class MyTableClass {
    // list the propeties here, ONLY WRITTEN ONCE
    constructor(
        readonly id?: string,
        readonly title?: string,
        readonly isDeleted?: boolean,
    ) {}
}

console.log(Object.keys(new MyTableClass()));  // prints out  ["id", "title", "isDeleted"] 

Constructor Trick in TypeScript Playground.

Getting Google+ profile picture url with user_id

If you use Flutter, then you can access it via people.googleapis.com endpoint, code uses google_sign_in library

import 'package:google_sign_in/google_sign_in.dart';

Future<String> getPhotoUrl(GoogleSignInAccount account, String userId) async {
  // final authentication = await account.authentication;
  final url = 'https://people.googleapis.com/v1/people/${userId}?personFields=photos';
  final response = await http.get(
    url,
    headers: await account.authHeaders
  );

  final data = json.decode(response.body);
  return data['photos'].first['url'];
}

You will get something like

{
  resourceName: people/998812322529259873423, 
  etag: %EgQBAzcabcQBAgUH, 
  photos: [{metadata: {primary: true, source: {type: PROFILE, id: 107721622529987673423}}, 
  url: https://lh3.googleusercontent.com/a-/abcdefmB2p1VWxLsNT9WSV0yqwuwo6o2Ba21sh_ra7CnrZ=s100}]
}

where url is an accessible image url.

How do I get 'date-1' formatted as mm-dd-yyyy using PowerShell?

This is the most simple solution for me:

just the current date

$tStamp = Get-Date -format yyyy_MM_dd_HHmmss

current date with some months added

$tStamp = Get-Date (get-date).AddMonths(6).Date -Format yyyyMMdd

How do I uninstall a package installed using npm link?

The package can be uninstalled using the same uninstall or rm command that can be used for removing installed packages. The only thing to keep in mind is that the link needs to be uninstalled globally - the --global flag needs to be provided.

In order to uninstall the globally linked foo package, the following command can be used (using sudo if necessary, depending on your setup and permissions)

sudo npm rm --global foo

This will uninstall the package.

To check whether a package is installed, the npm ls command can be used:

npm ls --global foo

Git command to display HEAD commit id?

Play with Bash:

git show HEAD | sed -n 1p | cut -d " " -f 2

Symfony 2 EntityManager injection in service

Note as of Symfony 3.3 EntityManager is depreciated. Use EntityManagerInterface instead.

namespace AppBundle\Service;

use Doctrine\ORM\EntityManagerInterface;

class Someclass {
    protected $em;

    public function __construct(EntityManagerInterface $entityManager)
    {
        $this->em = $entityManager;
    }

    public function somefunction() {
        $em = $this->em;
        ...
    }
}

Optimistic vs. Pessimistic locking

I would think of one more case when pessimistic locking would be a better choice.

For optimistic locking every participant in data modification must agree in using this kind of locking. But if someone modifies the data without taking care about the version column, this will spoil the whole idea of the optimistic locking.

How to use Regular Expressions (Regex) in Microsoft Excel both in-cell and loops

To make use of regular expressions directly in Excel formulas the following UDF (user defined function) can be of help. It more or less directly exposes regular expression functionality as an excel function.

How it works

It takes 2-3 parameters.

  1. A text to use the regular expression on.
  2. A regular expression.
  3. A format string specifying how the result should look. It can contain $0, $1, $2, and so on. $0 is the entire match, $1 and up correspond to the respective match groups in the regular expression. Defaults to $0.

Some examples

Extracting an email address:

=regex("Peter Gordon: [email protected], 47", "\w+@\w+\.\w+")
=regex("Peter Gordon: [email protected], 47", "\w+@\w+\.\w+", "$0")

Results in: [email protected]

Extracting several substrings:

=regex("Peter Gordon: [email protected], 47", "^(.+): (.+), (\d+)$", "E-Mail: $2, Name: $1")

Results in: E-Mail: [email protected], Name: Peter Gordon

To take apart a combined string in a single cell into its components in multiple cells:

=regex("Peter Gordon: [email protected], 47", "^(.+): (.+), (\d+)$", "$" & 1)
=regex("Peter Gordon: [email protected], 47", "^(.+): (.+), (\d+)$", "$" & 2)

Results in: Peter Gordon [email protected] ...

How to use

To use this UDF do the following (roughly based on this Microsoft page. They have some good additional info there!):

  1. In Excel in a Macro enabled file ('.xlsm') push ALT+F11 to open the Microsoft Visual Basic for Applications Editor.
  2. Add VBA reference to the Regular Expressions library (shamelessly copied from Portland Runners++ answer):
    1. Click on Tools -> References (please excuse the german screenshot) Tools -> References
    2. Find Microsoft VBScript Regular Expressions 5.5 in the list and tick the checkbox next to it.
    3. Click OK.
  3. Click on Insert Module. If you give your module a different name make sure the Module does not have the same name as the UDF below (e.g. naming the Module Regex and the function regex causes #NAME! errors).

    Second icon in the icon row -> Module

  4. In the big text window in the middle insert the following:

    Function regex(strInput As String, matchPattern As String, Optional ByVal outputPattern As String = "$0") As Variant
        Dim inputRegexObj As New VBScript_RegExp_55.RegExp, outputRegexObj As New VBScript_RegExp_55.RegExp, outReplaceRegexObj As New VBScript_RegExp_55.RegExp
        Dim inputMatches As Object, replaceMatches As Object, replaceMatch As Object
        Dim replaceNumber As Integer
    
        With inputRegexObj
            .Global = True
            .MultiLine = True
            .IgnoreCase = False
            .Pattern = matchPattern
        End With
        With outputRegexObj
            .Global = True
            .MultiLine = True
            .IgnoreCase = False
            .Pattern = "\$(\d+)"
        End With
        With outReplaceRegexObj
            .Global = True
            .MultiLine = True
            .IgnoreCase = False
        End With
    
        Set inputMatches = inputRegexObj.Execute(strInput)
        If inputMatches.Count = 0 Then
            regex = False
        Else
            Set replaceMatches = outputRegexObj.Execute(outputPattern)
            For Each replaceMatch In replaceMatches
                replaceNumber = replaceMatch.SubMatches(0)
                outReplaceRegexObj.Pattern = "\$" & replaceNumber
    
                If replaceNumber = 0 Then
                    outputPattern = outReplaceRegexObj.Replace(outputPattern, inputMatches(0).Value)
                Else
                    If replaceNumber > inputMatches(0).SubMatches.Count Then
                        'regex = "A to high $ tag found. Largest allowed is $" & inputMatches(0).SubMatches.Count & "."
                        regex = CVErr(xlErrValue)
                        Exit Function
                    Else
                        outputPattern = outReplaceRegexObj.Replace(outputPattern, inputMatches(0).SubMatches(replaceNumber - 1))
                    End If
                End If
            Next
            regex = outputPattern
        End If
    End Function
    
  5. Save and close the Microsoft Visual Basic for Applications Editor window.

console.log timestamps in Chrome?

I have this in most Node.JS apps. It also works in the browser.

function log() {
  const now = new Date();
  const currentDate = `[${now.toISOString()}]: `;
  const args = Array.from(arguments);
  args.unshift(currentDate);
  console.log.apply(console, args);
}

Javascript foreach loop on associative array object

This is very simple approach. The Advantage is you can get keys as well:

for (var key in array) {
    var value = array[key];
    console.log(key, value);
}

For ES6:

array.forEach(value => {
  console.log(value)
})  

For ES6: (If you want value, index and the array itself)

array.forEach((value, index, self) => {
  console.log(value, index, self)
})  

What causes the error "undefined reference to (some function)"?

It's a linker error. ld is the linker, so if you get an error message ending with "ld returned 1 exit status", that tells you that it's a linker error.

The error message tells you that none of the object files you're linking against contains a definition for avergecolumns. The reason for that is that the function you've defined is called averagecolumns (in other words: you misspelled the function name when calling the function (and presumably in the header file as well - otherwise you'd have gotten a different error at compile time)).

Fragment MyFragment not attached to Activity

I've faced two different scenarios here:

1) When I want the asynchronous task to finish anyway: imagine my onPostExecute does store data received and then call a listener to update views so, to be more efficient, I want the task to finish anyway so I have the data ready when user cames back. In this case I usually do this:

@Override
protected void onPostExecute(void result) {
    // do whatever you do to save data
    if (this.getView() != null) {
        // update views
    }
}

2) When I want the asynchronous task only to finish when views can be updated: the case you're proposing here, the task only updates the views, no data storage needed, so it has no clue for the task to finish if views are not longer being showed. I do this:

@Override
protected void onStop() {
    // notice here that I keep a reference to the task being executed as a class member:
    if (this.myTask != null && this.myTask.getStatus() == Status.RUNNING) this.myTask.cancel(true);
    super.onStop();
}

I've found no problem with this, although I also use a (maybe) more complex way that includes launching tasks from the activity instead of the fragments.

Wish this helps someone! :)

Copying one structure to another

Copying by plain assignment is best, since it's shorter, easier to read, and has a higher level of abstraction. Instead of saying (to the human reader of the code) "copy these bits from here to there", and requiring the reader to think about the size argument to the copy, you're just doing a plain assignment ("copy this value from here to here"). There can be no hesitation about whether or not the size is correct.

Also, if the structure is heavily padded, assignment might make the compiler emit something more efficient, since it doesn't have to copy the padding (and it knows where it is), but mempcy() doesn't so it will always copy the exact number of bytes you tell it to copy.

If your string is an actual array, i.e.:

struct {
  char string[32];
  size_t len;
} a, b;

strcpy(a.string, "hello");
a.len = strlen(a.string);

Then you can still use plain assignment:

b = a;

To get a complete copy. For variable-length data modelled like this though, this is not the most efficient way to do the copy since the entire array will always be copied.

Beware though, that copying structs that contain pointers to heap-allocated memory can be a bit dangerous, since by doing so you're aliasing the pointer, and typically making it ambiguous who owns the pointer after the copying operation.

For these situations a "deep copy" is really the only choice, and that needs to go in a function.

Spring Data JPA findOne() change to Optional how to use this?

Indeed, in the latest version of Spring Data, findOne returns an optional. If you want to retrieve the object from the Optional, you can simply use get() on the Optional. First of all though, a repository should return the optional to a service, which then handles the case in which the optional is empty. afterwards, the service should return the object to the controller.

This action could not be completed. Try Again (-22421)

I think my issue was that I had previously attempted to upload the same version number of my application and it either failed for another reason, or I cancelled it myself.

I changed the version of my app to a version which had not been used before. Cleaned my project. Re-archived it, then uploaded with no issues.

...... You need to INCREASE your version number, you can't make it smaller...

Iterate through DataSet

Just loop...

foreach(var table in DataSet1.Tables) {
    foreach(var col in table.Columns) {
       ...
    }
    foreach(var row in table.Rows) {
        object[] values = row.ItemArray;
        ...
    }
}

Removing ul indentation with CSS

This code will remove the indentation and list bullets.

ul {
    padding: 0;
    list-style-type: none;
}

http://jsfiddle.net/qeqtK/2/

Why is a div with "display: table-cell;" not affected by margin?

If you have div next each other like this

<div id="1" style="float:left; margin-right:5px">

</div>
<div id="2" style="float:left">

</div>

This should work!

Change Schema Name Of Table In SQL

Your Code is:

FROM
 dbo.Employees
TO
 exe.Employees

I tried with this query.

ALTER SCHEMA exe TRANSFER dbo.Employees

Just write create schema exe and execute it

How can I inspect element in chrome when right click is disabled?

Press F12 to Inspect Element and Ctrl+U to View Page Source

what is right way to do API call in react js?

You may want to check out the Flux Architecture. I also recommend checking out React-Redux Implementation. Put your api calls in your actions. It is much more cleaner than putting it all in the component.

Actions are sort of helper methods that you can call to change your application state or do api calls.

Shorter syntax for casting from a List<X> to a List<Y>?

This is not quite the answer to this question, but it may be useful for some: as @SWeko said, thanks to covariance and contravariance, List<X> can not be cast in List<Y>, but List<X> can be cast into IEnumerable<Y>, and even with implicit cast.

Example:

List<Y> ListOfY = new List<Y>();
List<X> ListOfX = (List<X>)ListOfY; // Compile error

but

List<Y> ListOfY = new List<Y>();
IEnumerable<X> EnumerableOfX = ListOfY;  // No issue

The big advantage is that it does not create a new list in memory.

Get path to execution directory of Windows Forms application

string apppath = 
    (new System.IO.FileInfo
    (System.Reflection.Assembly.GetExecutingAssembly().CodeBase)).DirectoryName;

Nesting CSS classes

Not possible with vanilla CSS. However you can use something like:

Sass makes CSS fun again. Sass is an extension of CSS3, adding nested rules, variables, mixins, selector inheritance, and more. It’s translated to well-formatted, standard CSS using the command line tool or a web-framework plugin.

Or

Rather than constructing long selector names to specify inheritance, in Less you can simply nest selectors inside other selectors. This makes inheritance clear and style sheets shorter.

Example:

#header {
  color: red;
  a {
    font-weight: bold;
    text-decoration: none;
  }
}

error: src refspec master does not match any

I had already committed the changes and added all the files, had the same origin as remote, still kept getting that error. My simple solution to this was just:

git push

How to upload a file in Django?

Not sure if there any disadvantages to this approach but even more minimal, in views.py:

entry = form.save()

# save uploaded file
if request.FILES['myfile']:
    entry.myfile.save(request.FILES['myfile']._name, request.FILES['myfile'], True)

format a Date column in a Data Frame

try this package, works wonders, and was made for date/time...

library(lubridate)
Portfolio$Date2 <- mdy(Portfolio.all$Date2)

How do I comment out a block of tags in XML?

In Notepad++ you can select few lines and use CTRL+Q which will automaticaly make block comments for selected lines.

How do I hide anchor text without hiding the anchor?

a { text-indent:-9999px; }

Tends to work well from my exprience.

How to write data to a text file without overwriting the current data

Look into the File class.

You can create a streamwriter with

StreamWriter sw = File.Create(....) 

You can open an existing file with

File.Open(...)

You can append text easily with

File.AppendAllText(...);

Get selected row item in DataGrid WPF

This is pretty simple in this DataGrid dg and item class is populated in datagrid and listblock1 is a basic frame.

private void DataGrid_SelectionChanged(object sender, SelectionChangedEventArgs e)
    {
        try
        {
            var row_list = (Item)dg.SelectedItem;
            listblock1.Content = "You Selected: " + row_list.FirstName + " " + row_list.LastName;
        }
        catch { }

    }
    public class Item
    {
        public string FirstName { get; set; }
        public string LastName { get; set; }
    }

How to change the floating label color of TextInputLayout

Found the answer, use android.support.design:hintTextAppearance attribute to set your own floating label appearance.

Example:

<android.support.design.widget.TextInputLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    app:hintTextAppearance="@style/TextAppearance.AppCompat">

    <EditText
        android:id="@+id/password"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="@string/prompt_password"/>
</android.support.design.widget.TextInputLayout>

CSS content property: is it possible to insert HTML instead of Text?

Unfortunately, this is not possible. Per the spec:

Generated content does not alter the document tree. In particular, it is not fed back to the document language processor (e.g., for reparsing).

In other words, for string values this means the value is always treated literally. It is never interpreted as markup, regardless of the document language in use.

As an example, using the given CSS with the following HTML:

<h1 class="header">Title</h1>

... will result in the following output:

<a href="#top">Back</a>Title

JavaFX 2.1 TableView refresh items

Based on Daniel De León's answer

public static void refresh_table(TableView table) {
    for (int i = 0; i < table.getColumns().size(); i++) {
        ((TableColumn)(table.getColumns().get(i))).setVisible(false);
        ((TableColumn)(table.getColumns().get(i))).setVisible(true);
    }
}

Brackets.io: Is there a way to auto indent / format <html>

You can install an indentator package.

Click on File > Extension Manager....

Look for the search field and type: Indentator > Install

Once Indentator is installed, you can use Ctrl + Alt + I

matplotlib savefig in jpeg format

I just updated matplotlib to 1.1.0 on my system and it now allows me to save to jpg with savefig.

To upgrade to matplotlib 1.1.0 with pip, use this command:

pip install -U 'http://sourceforge.net/projects/matplotlib/files/matplotlib/matplotlib-1.1.0/matplotlib-1.1.0.tar.gz/download'

EDIT (to respond to comment):

pylab is simply an aggregation of the matplotlib.pyplot and numpy namespaces (as well as a few others) jinto a single namespace.

On my system, pylab is just this:

from matplotlib.pylab import *
import matplotlib.pylab
__doc__ = matplotlib.pylab.__doc__

You can see that pylab is just another namespace in your matplotlib installation. Therefore, it doesn't matter whether or not you import it with pylab or with matplotlib.pyplot.

If you are still running into problem, then I'm guessing the macosx backend doesn't support saving plots to jpg. You could try using a different backend. See here for more information.

Hibernate throws org.hibernate.AnnotationException: No identifier specified for entity: com..domain.idea.MAE_MFEView

I think this issue following model class wrong import.

    import org.springframework.data.annotation.Id;

Normally, it should be:

    import javax.persistence.Id;

How to create a HTTP server in Android?

Consider this one: https://github.com/NanoHttpd/nanohttpd. Very small, written in Java. I used it without any problem.

Disabling Warnings generated via _CRT_SECURE_NO_DEPRECATE

you can disable security check. go to

Project -> Properties -> Configuration properties -> C/C++ -> Code Generation -> Security Check

and select Disable Security Check (/GS-)

How to create a horizontal loading progress bar?

For using the new progress bar

style="?android:attr/progressBarStyleHorizontal"

for the old grey color progress bar use

style="@android:style/Widget.ProgressBar.Horizontal"

in this one you have the option of changing the height by setting minHeight

The complete XML code is:

    <ProgressBar
    android:id="@+id/pbProcessing"
    style="?android:attr/progressBarStyleHorizontal"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_below="@+id/tvProcessing"
    android:indeterminateOnly="true"/>

indeterminateOnly is set to true for getting indeterminate horizontal progress bar