Programs & Examples On #Zcml

RVM is not a function, selecting rubies with 'rvm use ...' will not work

The error is due to rvm is not running as in login shell. Hence try the below command:

/bin/bash --login

You will able run rvm commands instantly as login shell in terminal.

Thanks!

Install Windows Service created in Visual Studio

You need to open the Service.cs file in the designer, right click it and choose the menu-option "Add Installer".

It won't install right out of the box... you need to create the installer class first.

Some reference on service installer:

How to: Add Installers to Your Service Application

Quite old... but this is what I am talking about:

Windows Services in C#: Adding the Installer (part 3)

By doing this, a ProjectInstaller.cs will be automaticaly created. Then you can double click this, enter the designer, and configure the components:

  • serviceInstaller1 has the properties of the service itself: Description, DisplayName, ServiceName and StartType are the most important.

  • serviceProcessInstaller1 has this important property: Account that is the account in which the service will run.

For example:

this.serviceProcessInstaller1.Account = ServiceAccount.LocalSystem;

Is there any sed like utility for cmd.exe?

If you don't want to install anything (I assume you want to add the script into some solution/program/etc that will be run in other machines), you could try creating a vbs script (lets say, replace.vbs):

Const ForReading = 1
Const ForWriting = 2

strFileName = Wscript.Arguments(0)
strOldText = Wscript.Arguments(1)
strNewText = Wscript.Arguments(2)

Set objFSO = CreateObject("Scripting.FileSystemObject")
Set objFile = objFSO.OpenTextFile(strFileName, ForReading)

strText = objFile.ReadAll
objFile.Close
strNewText = Replace(strText, strOldText, strNewText)

Set objFile = objFSO.OpenTextFile(strFileName, ForWriting)
objFile.Write strNewText
objFile.Close

And you run it like this:

cscript replace.vbs "C:\One.txt" "Robert" "Rob"

Which is similar to the sed version provided by "bill weaver", but I think this one is more friendly in terms of special (' > < / ) characters.

Btw, I didn't write this, but I can't recall where I got it from.

Bootstrap full-width text-input within inline-form

Try something like below to achieve your desired result

input {
    max-width: 100%;
}

Are HTTPS headers encrypted?

New answer to old question, sorry. I thought I'd add my $.02

The OP asked if the headers were encrypted.

They are: in transit.

They are NOT: when not in transit.

So, your browser's URL (and title, in some cases) can display the querystring (which usually contain the most sensitive details) and some details in the header; the browser knows some header information (content type, unicode, etc); and browser history, password management, favorites/bookmarks, and cached pages will all contain the querystring. Server logs on the remote end can also contain querystring as well as some content details.

Also, the URL isn't always secure: the domain, protocol, and port are visible - otherwise routers don't know where to send your requests.

Also, if you've got an HTTP proxy, the proxy server knows the address, usually they don't know the full querystring.

So if the data is moving, it's generally protected. If it's not in transit, it's not encrypted.

Not to nit pick, but data at the end is also decrypted, and can be parsed, read, saved, forwarded, or discarded at will. And, malware at either end can take snapshots of data entering (or exiting) the SSL protocol - such as (bad) Javascript inside a page inside HTTPS which can surreptitiously make http (or https) calls to logging websites (since access to local harddrive is often restricted and not useful).

Also, cookies are not encrypted under the HTTPS protocol, either. Developers wanting to store sensitive data in cookies (or anywhere else for that matter) need to use their own encryption mechanism.

As to cache, most modern browsers won't cache HTTPS pages, but that fact is not defined by the HTTPS protocol, it is entirely dependent on the developer of a browser to be sure not to cache pages received through HTTPS.

So if you're worried about packet sniffing, you're probably okay. But if you're worried about malware or someone poking through your history, bookmarks, cookies, or cache, you are not out of the water yet.

How to write a link like <a href="#id"> which link to the same page in PHP?

Edit:

Are you trying to do sth like this? See: http://twitter.github.com/bootstrap/javascript.html#tabs


See the working example: http://jsfiddle.net/U6aKT/

<a href="#id">go to id</a>
<div style="margin-top:2000px;"></div>
<a id="id">id</a>

How can I dynamically add items to a Java array?

Use an ArrayList or juggle to arrays to auto increment the array size.

Reset Excel to default borders

In Excel 2016 for Mac, I clicked the Excel menu, then clicked Preferences…

I then clicked the View icon.

whereupon I found a Gridlines Checkbox next to a Color Picker.

Regardless of whether the Gridlines checkbox os checked or not, if you change the color in the Color Picker dropdown menu, your cell borders will become that color. (I believe the change took place after i quit excel and opened the document the next day to continue working on it but I can't accurately remember.)

Changing the color picker back to Automatic will return your cell borders to the default (black) color on-the-fly.

N.B. Because I'm a newbie I cannot insert the screen shots I prepared ahead of time.

What are POD types in C++?

POD stands for Plain Old Data - that is, a class (whether defined with the keyword struct or the keyword class) without constructors, destructors and virtual members functions. Wikipedia's article on POD goes into a bit more detail and defines it as:

A Plain Old Data Structure in C++ is an aggregate class that contains only PODS as members, has no user-defined destructor, no user-defined copy assignment operator, and no nonstatic members of pointer-to-member type.

Greater detail can be found in this answer for C++98/03. C++11 changed the rules surrounding POD, relaxing them greatly, thus necessitating a follow-up answer here.

Twitter Bootstrap dropdown menu

It actually requires inclusion of Twitter Bootstrap's dropdown.js

http://getbootstrap.com/2.3.2/components.html

Fill remaining vertical space with CSS using display:flex

Make it simple : DEMO

_x000D_
_x000D_
section {_x000D_
  display: flex;_x000D_
  flex-flow: column;_x000D_
  height: 300px;_x000D_
}_x000D_
_x000D_
header {_x000D_
  background: tomato;_x000D_
  /* no flex rules, it will grow */_x000D_
}_x000D_
_x000D_
div {_x000D_
  flex: 1;  /* 1 and it will fill whole space left if no flex value are set to other children*/_x000D_
  background: gold;_x000D_
  overflow: auto;_x000D_
}_x000D_
_x000D_
footer {_x000D_
  background: lightgreen;_x000D_
  min-height: 60px;  /* min-height has its purpose :) , unless you meant height*/_x000D_
}
_x000D_
<section>_x000D_
  <header>_x000D_
    header: sized to content_x000D_
    <br/>(but is it really?)_x000D_
  </header>_x000D_
  <div>_x000D_
    main content: fills remaining space<br> x_x000D_
    <br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>_x000D_
    <!-- uncomment to see it break -->_x000D_
    x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br> x_x000D_
    <br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br> x_x000D_
    <br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br> x_x000D_
    <br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>_x000D_
    <!-- -->_x000D_
  </div>_x000D_
  <footer>_x000D_
    footer: fixed height in px_x000D_
  </footer>_x000D_
</section>
_x000D_
_x000D_
_x000D_

Full screen version

_x000D_
_x000D_
section {_x000D_
  display: flex;_x000D_
  flex-flow: column;_x000D_
  height: 100vh;_x000D_
}_x000D_
_x000D_
header {_x000D_
  background: tomato;_x000D_
  /* no flex rules, it will grow */_x000D_
}_x000D_
_x000D_
div {_x000D_
  flex: 1;_x000D_
  /* 1 and it will fill whole space left if no flex value are set to other children*/_x000D_
  background: gold;_x000D_
  overflow: auto;_x000D_
}_x000D_
_x000D_
footer {_x000D_
  background: lightgreen;_x000D_
  min-height: 60px;_x000D_
  /* min-height has its purpose :) , unless you meant height*/_x000D_
}_x000D_
_x000D_
body {_x000D_
  margin: 0;_x000D_
}
_x000D_
<section>_x000D_
  <header>_x000D_
    header: sized to content_x000D_
    <br/>(but is it really?)_x000D_
  </header>_x000D_
  <div>_x000D_
    main content: fills remaining space<br> x_x000D_
    <br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>_x000D_
    <!-- uncomment to see it break -->_x000D_
    x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br> x_x000D_
    <br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br> x_x000D_
    <br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br> x_x000D_
    <br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>_x000D_
    <!-- -->_x000D_
  </div>_x000D_
  <footer>_x000D_
    footer: fixed height in px_x000D_
  </footer>_x000D_
</section>
_x000D_
_x000D_
_x000D_

Android get image path from drawable as string

First check whether the file exists in SDCard. If the file doesnot exists in SDcard then you can set image using setImageResource() methodand passing default image from drawable folder

Sample Code

File imageFile = new File(absolutepathOfImage);//absolutepathOfImage is absolute path of image including its name
        if(!imageFile.exists()){//file doesnot exist in SDCard

        imageview.setImageResource(R.drawable.defaultImage);//set default image from drawable folder
        }

How can I check if PostgreSQL is installed or not via Linux script?

And if everything else fails from these great choice of answers, you can always use "find" like this. Or you may need to use sudo

If you are root, just type $$> find / -name 'postgres'

If you are a user, you will need sudo priv's to run it through all the directories

I run it this way, from the / base to find the whole path that the element is found in. This will return any files or directories with the "postgres" in it.

You could do the same thing looking for the pg_hba.conf or postgresql.conf files also.

Passing base64 encoded strings in URL

Yes and no.

The basic charset of base64 may in some cases collide with traditional conventions used in URLs. But many of base64 implementations allow you to change the charset to match URLs better or even come with one (like Python's urlsafe_b64encode()).

Another issue you may be facing is the limit of URL length or rather — lack of such limit. Because standards do not specify any maximum length, browsers, servers, libraries and other software working with HTTP protocol may define its' own limits.

C++ String array sorting

The multiset container uses a red-black tree to keep elements sorted.

// using the multiset container to sort a list of strings.
#include <iostream>
#include <set>
#include <string>
#include <vector>


std::vector<std::string> people = {
  "Joe",
  "Adam",
  "Mark",
  "Jesse",
  "Jess",
  "Fred",
  "Susie",
  "Jill",
  "Fred", // two freds.
  "Adam",
  "Jack",
  "Adam", // three adams.
  "Zeke",
  "Phil"};

int main(int argc, char **argv) {
  std::multiset<std::string> g(people.begin(), people.end()); // """sort"""
  std::vector<std::string> all_sorted (g.begin(), g.end());
  for (int i = 0; i < all_sorted.size(); i++) {
    std::cout << all_sorted[i] << std::endl;
  }
}

Sample Output:

Adam
Adam
Adam
Fred
Fred
Jack
Jess
Jesse
Jill
Joe
Mark
Phil
Susie
Zeke

Note the advantage is that the multiset stays sorted after insertions and deletions, great for displaying say active connections or what not.

Python: Maximum recursion depth exceeded

You can increment the stack depth allowed - with this, deeper recursive calls will be possible, like this:

import sys
sys.setrecursionlimit(10000) # 10000 is an example, try with different values

... But I'd advise you to first try to optimize your code, for instance, using iteration instead of recursion.

The Controls collection cannot be modified because the control contains code blocks (i.e. <% ... %>)

Just in case if you are using Telerik components and you have a reference in your javascript with <%= .... %> then wrap your script tag with a RadScriptBlock.

 <telerik:RadScriptBlock ID="radSript1" runat="server">
   <script type="text/javascript">
        //Your javascript
   </script>
</telerik>

Regards Örvar

Detect if user is scrolling

If you want detect when user scroll over certain div, you can do something like this:

window.onscroll = function() {
    var distanceScrolled = document.documentElement.scrollTop;
    console.log('Scrolled: ' + distanceScrolled);
}

For example, if your div appear after scroll until the position 112:

window.onscroll = function() {
    var distanceScrolled = document.documentElement.scrollTop;
    if (distanceScrolled > 112) {
      do something...
    }
}

But as you can see you don't need a div, just the offset distance you want something to happen.

What HTTP traffic monitor would you recommend for Windows?

Try Wireshark:

Wireshark is the world's foremost network protocol analyzer, and is the de facto (and often de jure) standard across many industries and educational institutions.

There is a bit of a learning curve but it is far and away the best tool available.

getElementById in React

You need to have your function in the componentDidMount lifecycle since this is the function that is called when the DOM has loaded.

Make use of refs to access the DOM element

<input type="submit" className="nameInput" id="name" value="cp-dev1" onClick={this.writeData} ref = "cpDev1"/>

  componentDidMount: function(){
    var name = React.findDOMNode(this.refs.cpDev1).value;
    this.someOtherFunction(name);
  }

See this answer for more info on How to access the dom element in React

Saving image from PHP URL

None of the answers here mention the fact that a URL image can be compressed (gzip), and none of them work in this case.

There are two solutions that can get you around this:

The first is to use the cURL method and set the curl_setopt CURLOPT_ENCODING, '':

// ... image validation ...

// Handle compression & redirection automatically
$ch = curl_init($image_url);
$fp = fopen($dest_path, 'wb');

curl_setopt($ch, CURLOPT_FILE, $fp);
// Exclude header data
curl_setopt($ch, CURLOPT_HEADER, 0);
// Follow redirected location
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, 1);
// Auto detect decoding of the response | identity, deflate, & gzip
curl_setopt($ch, CURLOPT_ENCODING, '');

curl_exec($ch);

curl_close($ch);
fclose($fp);

It works, but from hundreds of tests of different images (png, jpg, ico, gif, svg), it is not the most reliable way.

What worked out best is to detect whether an image url has content encoding (e.g. gzip):

// ... image validation ...

// Fetch all headers from URL
$data = get_headers($image_url, true);

// Check if content encoding is set
$content_encoding = isset($data['Content-Encoding']) ? $data['Content-Encoding'] : null;

// Set gzip decode flag
$gzip_decode = ($content_encoding == 'gzip') ? true : false;

if ($gzip_decode)
{
    // Get contents and use gzdecode to "unzip" data
    file_put_contents($dest_path, gzdecode(file_get_contents($image_url)));
}
else
{
    // Use copy method
    copy($image_url, $dest_path);
}

For more information regarding gzdecode see this thread. So far this works fine. If there's anything that can be done better, let us know in the comments below.

HTTP Ajax Request via HTTPS Page

From the javascript I tried from several ways and I could not.

You need an server side solution, for example on c# I did create an controller that call to the http, en deserialize the object, and the result is that when I call from javascript, I'm doing an request from my https://domain to my htpps://domain. Please see my c# code:

[Authorize]
public class CurrencyServicesController : Controller
{
    HttpClient client;
    //GET: CurrencyServices/Consultar?url=valores?moedas=USD&alt=json
    public async Task<dynamic> Consultar(string url)
    {
        client = new HttpClient();
        client.BaseAddress = new Uri("http://api.promasters.net.br/cotacao/v1/");
        client.DefaultRequestHeaders.Accept.Add(new System.Net.Http.Headers.MediaTypeWithQualityHeaderValue("application/json"));
        System.Net.Http.HttpResponseMessage response = client.GetAsync(url).Result;

        var FromURL = response.Content.ReadAsStringAsync().Result;

        return JsonConvert.DeserializeObject(FromURL);
    }

And let me show to you my client side (Javascript)

<script async>
$(document).ready(function (data) {

    var TheUrl = '@Url.Action("Consultar", "CurrencyServices")?url=valores';
    $.getJSON(TheUrl)
        .done(function (data) {
            $('#DolarQuotation').html(
                '$ ' + data.valores.USD.valor.toFixed(2) + ','
            );
            $('#EuroQuotation').html(
                '€ ' + data.valores.EUR.valor.toFixed(2) + ','
            );

            $('#ARGPesoQuotation').html(
                'Ar$ ' + data.valores.ARS.valor.toFixed(2) + ''
            );

        });       

});

I wish that this help you! Greetings

How to get Real IP from Visitor?

Proxies may send a HTTP_X_FORWARDED_FOR header but even that is optional.

Also keep in mind that visitors may share IP addresses; University networks, large companies and third-world/low-budget ISPs tend to share IPs over many users.

XmlSerializer: remove unnecessary xsi and xsd namespaces

Since Dave asked for me to repeat my answer to Omitting all xsi and xsd namespaces when serializing an object in .NET, I have updated this post and repeated my answer here from the afore-mentioned link. The example used in this answer is the same example used for the other question. What follows is copied, verbatim.


After reading Microsoft's documentation and several solutions online, I have discovered the solution to this problem. It works with both the built-in XmlSerializer and custom XML serialization via IXmlSerialiazble.

To whit, I'll use the same MyTypeWithNamespaces XML sample that's been used in the answers to this question so far.

[XmlRoot("MyTypeWithNamespaces", Namespace="urn:Abracadabra", IsNullable=false)]
public class MyTypeWithNamespaces
{
    // As noted below, per Microsoft's documentation, if the class exposes a public
    // member of type XmlSerializerNamespaces decorated with the 
    // XmlNamespacesDeclarationAttribute, then the XmlSerializer will utilize those
    // namespaces during serialization.
    public MyTypeWithNamespaces( )
    {
        this._namespaces = new XmlSerializerNamespaces(new XmlQualifiedName[] {
            // Don't do this!! Microsoft's documentation explicitly says it's not supported.
            // It doesn't throw any exceptions, but in my testing, it didn't always work.

            // new XmlQualifiedName(string.Empty, string.Empty),  // And don't do this:
            // new XmlQualifiedName("", "")

            // DO THIS:
            new XmlQualifiedName(string.Empty, "urn:Abracadabra") // Default Namespace
            // Add any other namespaces, with prefixes, here.
        });
    }

    // If you have other constructors, make sure to call the default constructor.
    public MyTypeWithNamespaces(string label, int epoch) : this( )
    {
        this._label = label;
        this._epoch = epoch;
    }

    // An element with a declared namespace different than the namespace
    // of the enclosing type.
    [XmlElement(Namespace="urn:Whoohoo")]
    public string Label
    {
        get { return this._label; }
        set { this._label = value; }
    }
    private string _label;

    // An element whose tag will be the same name as the property name.
    // Also, this element will inherit the namespace of the enclosing type.
    public int Epoch
    {
        get { return this._epoch; }
        set { this._epoch = value; }
    }
    private int _epoch;

    // Per Microsoft's documentation, you can add some public member that
    // returns a XmlSerializerNamespaces object. They use a public field,
    // but that's sloppy. So I'll use a private backed-field with a public
    // getter property. Also, per the documentation, for this to work with
    // the XmlSerializer, decorate it with the XmlNamespaceDeclarations
    // attribute.
    [XmlNamespaceDeclarations]
    public XmlSerializerNamespaces Namespaces
    {
        get { return this._namespaces; }
    }
    private XmlSerializerNamespaces _namespaces;
}

That's all to this class. Now, some objected to having an XmlSerializerNamespaces object somewhere within their classes; but as you can see, I neatly tucked it away in the default constructor and exposed a public property to return the namespaces.

Now, when it comes time to serialize the class, you would use the following code:

MyTypeWithNamespaces myType = new MyTypeWithNamespaces("myLabel", 42);

/******
   OK, I just figured I could do this to make the code shorter, so I commented out the
   below and replaced it with what follows:

// You have to use this constructor in order for the root element to have the right namespaces.
// If you need to do custom serialization of inner objects, you can use a shortened constructor.
XmlSerializer xs = new XmlSerializer(typeof(MyTypeWithNamespaces), new XmlAttributeOverrides(),
    new Type[]{}, new XmlRootAttribute("MyTypeWithNamespaces"), "urn:Abracadabra");

******/
XmlSerializer xs = new XmlSerializer(typeof(MyTypeWithNamespaces),
    new XmlRootAttribute("MyTypeWithNamespaces") { Namespace="urn:Abracadabra" });

// I'll use a MemoryStream as my backing store.
MemoryStream ms = new MemoryStream();

// This is extra! If you want to change the settings for the XmlSerializer, you have to create
// a separate XmlWriterSettings object and use the XmlTextWriter.Create(...) factory method.
// So, in this case, I want to omit the XML declaration.
XmlWriterSettings xws = new XmlWriterSettings();
xws.OmitXmlDeclaration = true;
xws.Encoding = Encoding.UTF8; // This is probably the default
// You could use the XmlWriterSetting to set indenting and new line options, but the
// XmlTextWriter class has a much easier method to accomplish that.

// The factory method returns a XmlWriter, not a XmlTextWriter, so cast it.
XmlTextWriter xtw = (XmlTextWriter)XmlTextWriter.Create(ms, xws);
// Then we can set our indenting options (this is, of course, optional).
xtw.Formatting = Formatting.Indented;

// Now serialize our object.
xs.Serialize(xtw, myType, myType.Namespaces);

Once you have done this, you should get the following output:

<MyTypeWithNamespaces>
    <Label xmlns="urn:Whoohoo">myLabel</Label>
    <Epoch>42</Epoch>
</MyTypeWithNamespaces>

I have successfully used this method in a recent project with a deep hierachy of classes that are serialized to XML for web service calls. Microsoft's documentation is not very clear about what to do with the publicly accesible XmlSerializerNamespaces member once you've created it, and so many think it's useless. But by following their documentation and using it in the manner shown above, you can customize how the XmlSerializer generates XML for your classes without resorting to unsupported behavior or "rolling your own" serialization by implementing IXmlSerializable.

It is my hope that this answer will put to rest, once and for all, how to get rid of the standard xsi and xsd namespaces generated by the XmlSerializer.

UPDATE: I just want to make sure I answered the OP's question about removing all namespaces. My code above will work for this; let me show you how. Now, in the example above, you really can't get rid of all namespaces (because there are two namespaces in use). Somewhere in your XML document, you're going to need to have something like xmlns="urn:Abracadabra" xmlns:w="urn:Whoohoo. If the class in the example is part of a larger document, then somewhere above a namespace must be declared for either one of (or both) Abracadbra and Whoohoo. If not, then the element in one or both of the namespaces must be decorated with a prefix of some sort (you can't have two default namespaces, right?). So, for this example, Abracadabra is the default namespace. I could inside my MyTypeWithNamespaces class add a namespace prefix for the Whoohoo namespace like so:

public MyTypeWithNamespaces
{
    this._namespaces = new XmlSerializerNamespaces(new XmlQualifiedName[] {
        new XmlQualifiedName(string.Empty, "urn:Abracadabra"), // Default Namespace
        new XmlQualifiedName("w", "urn:Whoohoo")
    });
}

Now, in my class definition, I indicated that the <Label/> element is in the namespace "urn:Whoohoo", so I don't need to do anything further. When I now serialize the class using my above serialization code unchanged, this is the output:

<MyTypeWithNamespaces xmlns:w="urn:Whoohoo">
    <w:Label>myLabel</w:Label>
    <Epoch>42</Epoch>
</MyTypeWithNamespaces>

Because <Label> is in a different namespace from the rest of the document, it must, in someway, be "decorated" with a namespace. Notice that there are still no xsi and xsd namespaces.


This ends my answer to the other question. But I wanted to make sure I answered the OP's question about using no namespaces, as I feel I didn't really address it yet. Assume that <Label> is part of the same namespace as the rest of the document, in this case urn:Abracadabra:

<MyTypeWithNamespaces>
    <Label>myLabel<Label>
    <Epoch>42</Epoch>
</MyTypeWithNamespaces>

Your constructor would look as it would in my very first code example, along with the public property to retrieve the default namespace:

// As noted below, per Microsoft's documentation, if the class exposes a public
// member of type XmlSerializerNamespaces decorated with the 
// XmlNamespacesDeclarationAttribute, then the XmlSerializer will utilize those
// namespaces during serialization.
public MyTypeWithNamespaces( )
{
    this._namespaces = new XmlSerializerNamespaces(new XmlQualifiedName[] {
        new XmlQualifiedName(string.Empty, "urn:Abracadabra") // Default Namespace
    });
}

[XmlNamespaceDeclarations]
public XmlSerializerNamespaces Namespaces
{
    get { return this._namespaces; }
}
private XmlSerializerNamespaces _namespaces;

Then, later, in your code that uses the MyTypeWithNamespaces object to serialize it, you would call it as I did above:

MyTypeWithNamespaces myType = new MyTypeWithNamespaces("myLabel", 42);

XmlSerializer xs = new XmlSerializer(typeof(MyTypeWithNamespaces),
    new XmlRootAttribute("MyTypeWithNamespaces") { Namespace="urn:Abracadabra" });

...

// Above, you'd setup your XmlTextWriter.

// Now serialize our object.
xs.Serialize(xtw, myType, myType.Namespaces);

And the XmlSerializer would spit back out the same XML as shown immediately above with no additional namespaces in the output:

<MyTypeWithNamespaces>
    <Label>myLabel<Label>
    <Epoch>42</Epoch>
</MyTypeWithNamespaces>

C# DateTime to UTC Time without changing the time

You can use the overloaded constructor of DateTime:

DateTime utcDateTime = new DateTime(dateTime.Year, dateTime.Month, dateTime.Day, dateTime.Hour, dateTime.Minute, dateTime.Second, DateTimeKind.Utc);

How do you get total amount of RAM the computer has?

If you happen to be using Mono, then you might be interested to know that Mono 2.8 (to be released later this year) will have a performance counter which reports the physical memory size on all the platforms Mono runs on (including Windows). You would retrieve the value of the counter using this code snippet:

using System;
using System.Diagnostics;

class app
{
   static void Main ()
   {
       var pc = new PerformanceCounter ("Mono Memory", "Total Physical Memory");
       Console.WriteLine ("Physical RAM (bytes): {0}", pc.RawValue);
   }
}

If you are interested in C code which provides the performance counter, it can be found here.

Like Operator in Entity Framework?

This is an old post now, but for anyone looking for the answer, this link should help. Go to this answer if you are already using EF 6.2.x. To this answer if you're using EF Core 2.x

Short version:

SqlFunctions.PatIndex method - returns the starting position of the first occurrence of a pattern in a specified expression, or zeros if the pattern is not found, on all valid text and character data types

Namespace: System.Data.Objects.SqlClient Assembly: System.Data.Entity (in System.Data.Entity.dll)

A bit of an explanation also appears in this forum thread.

How to add external library in IntelliJ IDEA?

Easier procedure on latest versions:

  • Copy jar to libs directory in the app (you can create the directory it if not there)
  • Refresh project so libs show up in the structure (right click on project top level, refresh/synchronize)
  • Expand libs and right click on the jar
  • Select "Add as Library"

Done

Android: alternate layout xml for landscape mode

By default, the layouts in /res/layout are applied to both portrait and landscape.

If you have for example

/res/layout/main.xml

you can add a new folder /res/layout-land, copy main.xml into it and make the needed adjustments.

orientation

See also http://www.androidpeople.com/android-portrait-amp-landscape-differeent-layouts and http://www.devx.com/wireless/Article/40792/1954 for some more options.

ListView item background via custom selector

FrostWire Team over here.

All the selector crap api doesn't work as expected. After trying all the solutions presented in this thread to no good, we just solved the problem at the moment of inflating the ListView Item.

  1. Make sure your item keeps it's state, we did it as a member variable of the MenuItem (boolean selected)

  2. When you inflate, ask if the underlying item is selected, if so, just set the drawable resource that you want as the background (be it a 9patch or whatever). Make sure your adapter is aware of this and that it calls notifyDataChanged() when something has been selected.

        @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        View rowView = convertView;
        if (rowView == null) {
            LayoutInflater inflater = act.getLayoutInflater();
            rowView = inflater.inflate(R.layout.slidemenu_listitem, null);
            MenuItemHolder viewHolder = new MenuItemHolder();
            viewHolder.label = (TextView) rowView.findViewById(R.id.slidemenu_item_label);
            viewHolder.icon = (ImageView) rowView.findViewById(R.id.slidemenu_item_icon);
            rowView.setTag(viewHolder);
        }
    
        MenuItemHolder holder = (MenuItemHolder) rowView.getTag();
        String s = items[position].label;
        holder.label.setText(s);
        holder.icon.setImageDrawable(items[position].icon);
    
        //Here comes the magic
        rowView.setSelected(items[position].selected);
    
        rowView.setBackgroundResource((rowView.isSelected()) ? R.drawable.slidemenu_item_background_selected : R.drawable.slidemenu_item_background);
    
        return rowView;
    }
    

It'd be really nice if the selectors would actually work, in theory it's a nice and elegant solution, but it seems like it's broken. KISS.

Is there a null-coalescing (Elvis) operator or safe navigation operator in javascript?

i think lodash _.get() can help here, as in _.get(user, 'name'), and more complex tasks like _.get(o, 'a[0].b.c', 'default-value')

Use :hover to modify the css of another class?

You can do it by making the following CSS. you can put here the css you need to affect child class in case of hover on the root

_x000D_
_x000D_
.root:hover    .child {_x000D_
   _x000D_
}
_x000D_
_x000D_
_x000D_

YouTube URL in Video Tag

The most straight forward answer to this question is: You can't.

Youtube doesn't output their video's in the right format, thus they can't be embedded in a
<video/> element.

There are a few solutions posted using javascript, but don't trust on those, they all need a fallback, and won't work cross-browser.

Including non-Python files with setup.py

Probably the best way to do this is to use the setuptools package_data directive. This does mean using setuptools (or distribute) instead of distutils, but this is a very seamless "upgrade".

Here's a full (but untested) example:

from setuptools import setup, find_packages

setup(
    name='your_project_name',
    version='0.1',
    description='A description.',
    packages=find_packages(exclude=['ez_setup', 'tests', 'tests.*']),
    package_data={'': ['license.txt']},
    include_package_data=True,
    install_requires=[],
)

Note the specific lines that are critical here:

package_data={'': ['license.txt']},
include_package_data=True,

package_data is a dict of package names (empty = all packages) to a list of patterns (can include globs). For example, if you want to only specify files within your package, you can do that too:

package_data={'yourpackage': ['*.txt', 'path/to/resources/*.txt']}

The solution here is definitely not to rename your non-py files with a .py extension.

See Ian Bicking's presentation for more info.

UPDATE: Another [Better] Approach

Another approach that works well if you just want to control the contents of the source distribution (sdist) and have files outside of the package (e.g. top-level directory) is to add a MANIFEST.in file. See the Python documentation for the format of this file.

Since writing this response, I have found that using MANIFEST.in is typically a less frustrating approach to just make sure your source distribution (tar.gz) has the files you need.

For example, if you wanted to include the requirements.txt from top-level, recursively include the top-level "data" directory:

include requirements.txt
recursive-include data *

Nevertheless, in order for these files to be copied at install time to the package’s folder inside site-packages, you’ll need to supply include_package_data=True to the setup() function. See Adding Non-Code Files for more information.

how to attach url link to an image?

"How to attach url link to an image?"

You do it like this:

<a href="http://www.google.com"><img src="http://www.google.com/intl/en_ALL/images/logo.gif"/></a>

See it in action.

Android error: Failed to install *.apk on device *: timeout

I have encountered the same problem and tried to change the ADB connection timeout. That did not work. I switched between my PC's USB ports (front -> back) and it fixed the problem!!!

Convert time span value to format "hh:mm Am/Pm" using C#

You can try this:

   string timeexample= string.Format("{0:hh:mm:ss tt}", DateTime.Now);

you can remove hh or mm or ss or tt according your need where hh is hour in 12 hr formate, mm is minutes,ss is seconds,and tt is AM/PM.

Android: Remove all the previous activities from the back stack

One possible solution what I can suggest you is to add android:launchMode="singleTop" in the manifest for my ProfileActivity. and when log out is clicked u can logoff starting again you LoginActivity. on logout u can call this.

Intent in = new Intent(Profile.this,Login.class);
                in.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
                startActivity(in);
                finish();

Try-catch speeding up my code?

9 years later and the bug is still there! You can see it easily with:

   static void Main( string[] args )
    {
      int hundredMillion = 1000000;
      DateTime start = DateTime.Now;
      double sqrt;
      for (int i=0; i < hundredMillion; i++)
      {
        sqrt = Math.Sqrt( DateTime.Now.ToOADate() );
      }
      DateTime end = DateTime.Now;

      double sqrtMs = (end - start).TotalMilliseconds;

      Console.WriteLine( "Elapsed milliseconds: " + sqrtMs );

      DateTime start2 = DateTime.Now;

      double sqrt2;
      for (int i = 0; i < hundredMillion; i++)
      {
        try
        {
          sqrt2 = Math.Sqrt( DateTime.Now.ToOADate() );
        }
        catch (Exception e)
        {
          int br = 0;
        }
      }
      DateTime end2 = DateTime.Now;

      double sqrtMsTryCatch = (end2 - start2).TotalMilliseconds;

      Console.WriteLine( "Elapsed milliseconds: " + sqrtMsTryCatch );

      Console.WriteLine( "ratio is " + sqrtMsTryCatch / sqrtMs );

      Console.ReadLine();
    }

The ratio is less than one on my machine, running the latest version of MSVS 2019, .NET 4.6.1

Export specific rows from a PostgreSQL table as INSERT SQL script

For a data-only export use COPY.
You get a file with one table row per line as plain text (not INSERT commands), it's smaller and faster:

COPY (SELECT * FROM nyummy.cimory WHERE city = 'tokio') TO '/path/to/file.csv';

Import the same to another table of the same structure anywhere with:

COPY other_tbl FROM '/path/to/file.csv';

COPY writes and read files local to the server, unlike client programs like pg_dump or psql which read and write files local to the client. If both run on the same machine, it doesn't matter much, but it does for remote connections.

There is also the \copy command of psql that:

Performs a frontend (client) copy. This is an operation that runs an SQL COPY command, but instead of the server reading or writing the specified file, psql reads or writes the file and routes the data between the server and the local file system. This means that file accessibility and privileges are those of the local user, not the server, and no SQL superuser privileges are required.

Easy way to print Perl array? (with a little formatting)

Using Data::Dumper :

use strict;
use Data::Dumper;

my $GRANTstr = 'SELECT, INSERT, UPDATE, DELETE, LOCK TABLES, EXECUTE, TRIGGER';
$GRANTstr    =~ s/, /,/g;
my @GRANTs   = split /,/ , $GRANTstr;

print Dumper(@GRANTs) . "===\n\n";

print Dumper(\@GRANTs) . "===\n\n";

print Data::Dumper->Dump([\@GRANTs], [qw(GRANTs)]);

Generates three different output styles:

$VAR1 = 'SELECT';
$VAR2 = 'INSERT';
$VAR3 = 'UPDATE';
$VAR4 = 'DELETE';
$VAR5 = 'LOCK TABLES';
$VAR6 = 'EXECUTE';
$VAR7 = 'TRIGGER';
===

$VAR1 = [
          'SELECT',
          'INSERT',
          'UPDATE',
          'DELETE',
          'LOCK TABLES',
          'EXECUTE',
          'TRIGGER'
        ];
===

$GRANTs = [
            'SELECT',
            'INSERT',
            'UPDATE',
            'DELETE',
            'LOCK TABLES',
            'EXECUTE',
            'TRIGGER'
          ];

What's the best strategy for unit-testing database-driven applications?

I have been asking this question for a long time, but I think there is no silver bullet for that.

What I currently do is mocking the DAO objects and keeping a in memory representation of a good collection of objects that represent interesting cases of data that could live on the database.

The main problem I see with that approach is that you're covering only the code that interacts with your DAO layer, but never testing the DAO itself, and in my experience I see that a lot of errors happen on that layer as well. I also keep a few unit tests that run against the database (for the sake of using TDD or quick testing locally), but those tests are never run on my continuous integration server, since we don't keep a database for that purpose and I think tests that run on CI server should be self-contained.

Another approach I find very interesting, but not always worth since is a little time consuming, is to create the same schema you use for production on an embedded database that just runs within the unit testing.

Even though there's no question this approach improves your coverage, there are a few drawbacks, since you have to be as close as possible to ANSI SQL to make it work both with your current DBMS and the embedded replacement.

No matter what you think is more relevant for your code, there are a few projects out there that may make it easier, like DbUnit.

Ruby on Rails - Import Data from a CSV file

This can help. It has code examples too:

http://csv-mapper.rubyforge.org/

Or for a rake task for doing the same:

http://erikonrails.snowedin.net/?p=212

How do I loop through a list by twos?

The simplest in my opinion is just this:

it = iter([1,2,3,4,5,6])
for x, y in zip(it, it):
    print x, y

Out: 1 2
     3 4
     5 6

No extra imports or anything. And very elegant, in my opinion.

How to convert array values to lowercase in PHP?

array_map() is the correct method. But, if you want to convert specific array values or all array values to lowercase one by one, you can use strtolower().

for($i=0; $i < count($array1); $i++) {
    $array1[$i] = strtolower($array1[$i]);
}

Is there an R function for finding the index of an element in a vector?

The function match works on vectors:

x <- sample(1:10)
x
# [1]  4  5  9  3  8  1  6 10  7  2
match(c(4,8),x)
# [1] 1 5

match only returns the first encounter of a match, as you requested. It returns the position in the second argument of the values in the first argument.

For multiple matching, %in% is the way to go:

x <- sample(1:4,10,replace=TRUE)
x
# [1] 3 4 3 3 2 3 1 1 2 2
which(x %in% c(2,4))
# [1]  2  5  9 10

%in% returns a logical vector as long as the first argument, with a TRUE if that value can be found in the second argument and a FALSE otherwise.

How to semantically add heading to a list

As Felipe Alsacreations has already said, the first option is fine.

If you want to ensure that nothing below the list is interpreted as belonging to the heading, that's exactly what the HTML5 sectioning content elements are for. So, for instance you could do

<h2>About Fruits</h2>
<section>
  <h3>Fruits I Like:</h3>
  <ul>
    <li>Apples</li>
    <li>Bananas</li>
    <li>Oranges</li>
  </ul>
</section>
<!-- anything here is part of the "About Fruits" section but does not 
     belong to the "Fruits I Like" section. -->

What is the reason for java.lang.IllegalArgumentException: No enum const class even though iterating through values() works just fine?

Instead of defining: COLUMN_HEADINGS("columnHeadings")

Try defining it as: COLUMNHEADINGS("columnHeadings")

Then when you call getByName(String name) method, call it with the upper-cased String like this: getByName(myStringVariable.toUpperCase())

I had the same problem as you, and this worked for me.

multiple ways of calling parent method in php

Unless I am misunderstanding the question, I would almost always use $this->get_species because the subclass (in this case dog) could overwrite that method since it does extend it. If the class dog doesn't redefine the method then both ways are functionally equivalent but if at some point in the future you decide you want the get_species method in dog should print "dog" then you would have to go back through all the code and change it.

When you use $this it is actually part of the object which you created and so will always be the most up-to-date as well (if the property being used has changed somehow in the lifetime of the object) whereas using the parent class is calling the static class method.

How to check if number is divisible by a certain number?

n % x == 0

Means that n can be divided by x. So... for instance, in your case:

boolean isDivisibleBy20 = number % 20 == 0;

Also, if you want to check whether a number is even or odd (whether it is divisible by 2 or not), you can use a bitwise operator:

boolean even = (number & 1) == 0;
boolean odd  = (number & 1) != 0;

Setting query string using Fetch GET request

You can use #stringify from query string

import { stringify } from 'query-string';

fetch(`https://example.org?${stringify(params)}`)

How do I use DrawerLayout to display over the ActionBar/Toolbar and under the status bar?

The above all approaches are correct and may be working . I have created a working demo following the above guide and tested on 2.x to 5.x

You can clone from Github

The important thing to play around is in Main Activity

toolbar = (Toolbar) findViewById(R.id.toolbar);
res = this.getResources();

this.setSupportActionBar(toolbar);
ActionBar actionBar = getSupportActionBar();
actionBar.setDisplayHomeAsUpEnabled(true);
actionBar.setHomeButtonEnabled(true);
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) { 
    ScrimInsetsFrameLayout scrimInsetsFrameLayout = (ScrimInsetsFrameLayout)
            findViewById(R.id.linearLayout);
    scrimInsetsFrameLayout.setOnInsetsCallback(this);
} 

and the call back

@Override
public void onInsetsChanged(Rect insets) {
    Toolbar toolbar = this.toolbar;
    ViewGroup.MarginLayoutParams lp = (ViewGroup.MarginLayoutParams)
        toolbar.getLayoutParams();
    lp.topMargin = insets.top;
    int top = insets.top;
    insets.top += toolbar.getHeight();
    toolbar.setLayoutParams(lp);
    insets.top = top; // revert
}

Absolutely the Theme for V21 does the magic

<style name="AppTheme" parent="Theme.AppCompat.Light.NoActionBar">
    <!-- API 21 theme customizations can go here. -->
    <item name="colorPrimary">@color/colorPrimary</item>
    <item name="colorPrimaryDark">@color/colorPrimaryDark</item>
    <item name="colorAccent">@color/accent_material_light</item>
    <item name="windowActionModeOverlay">true</item>
    <item name="android:windowDrawsSystemBarBackgrounds">true</item>
    <item name="android:statusBarColor">@android:color/transparent</item>
    <item name="android:windowTranslucentStatus">true</item>
</style>

and the ScrimInsetsFrameLayout

Now this come more easy with new Design Support library

compile 'com.android.support:design:22.2.0'

clone from @Chris Banes https://github.com/chrisbanes/cheesesquare

How to ignore HTML element from tabindex?

Just add the attribute disabled to the element (or use jQuery to do it for you). Disabled prevents the input from being focused or selected at all.

What can lead to "IOError: [Errno 9] Bad file descriptor" during os.system()?

You get this error message if a Python file was closed from "the outside", i.e. not from the file object's close() method:

>>> f = open(".bashrc")
>>> os.close(f.fileno())
>>> del f
close failed in file object destructor:
IOError: [Errno 9] Bad file descriptor

The line del f deletes the last reference to the file object, causing its destructor file.__del__ to be called. The internal state of the file object indicates the file is still open since f.close() was never called, so the destructor tries to close the file. The OS subsequently throws an error because of the attempt to close a file that's not open.

Since the implementation of os.system() does not create any Python file objects, it does not seem likely that the system() call is the origin of the error. Maybe you could show a bit more code?

Difference between Dictionary and Hashtable

Dictionary is typed (so valuetypes don't need boxing), a Hashtable isn't (so valuetypes need boxing). Hashtable has a nicer way of obtaining a value than dictionary IMHO, because it always knows the value is an object. Though if you're using .NET 3.5, it's easy to write an extension method for dictionary to get similar behavior.

If you need multiple values per key, check out my sourcecode of MultiValueDictionary here: multimap in .NET

typesafe select onChange event using reactjs and typescript

The easiest way is to add a type to the variable that is receiving the value, like this:

var value: string = (event.target as any).value;

Or you could cast the value property as well as event.target like this:

var value = ((event.target as any).value as string);

Edit:

Lastly, you can define what EventTarget.value is in a separate .d.ts file. However, the type will have to be compatible where it's used elsewhere, and you'll just end up using any again anyway.

globals.d.ts

interface EventTarget {
    value: any;
}

Finding the mode of a list

def mode(data):
    lst =[]
    hgh=0
    for i in range(len(data)):
        lst.append(data.count(data[i]))
    m= max(lst)
    ml = [x for x in data if data.count(x)==m ] #to find most frequent values
    mode = []
    for x in ml: #to remove duplicates of mode
        if x not in mode:
        mode.append(x)
    return mode
print mode([1,2,2,2,2,7,7,5,5,5,5])

How to update npm

sudo npm install npm@latest -g

This worked for me in ubuntu 18.04

Merge trunk to branch in Subversion

Is there something that prevents you from merging all revisions on trunk since the last merge?

svn merge -rLastRevisionMergedFromTrunkToBranch:HEAD url/of/trunk path/to/branch/wc

should work just fine. At least if you want to merge all changes on trunk to your branch.

How to loop an object in React?

You can use it in a more compact way as:

var tifs = {1: 'Joe', 2: 'Jane'};
...

return (
   <select id="tif" name="tif" onChange={this.handleChange}>  
      { Object.entries(tifs).map((t,k) => <option key={k} value={t[0]}>{t[1]}</option>) }          
   </select>
)

And another slightly different flavour:

 Object.entries(tifs).map(([key,value],i) => <option key={i} value={key}>{value}</option>)  

"date(): It is not safe to rely on the system's timezone settings..."

If you don't have access to the file php.ini, create or edit a .htaccess file in the root of your domain or sub and add this (generated by cpanel):

<IfModule mime_module>
AddType application/x-httpd-ea-php56 .php .php5 .phtml
</IfModule>

<IfModule php5_module>
php_value date.timezone "America/New_York"
</IfModule>

<IfModule lsapi_module>
php_value date.timezone "America/New_York"
</IfModule>

jQuery: get parent tr for selected radio button

Try this.

You don't need to prefix attribute name by @ in jQuery selector. Use closest() method to get the closest parent element matching the selector.

$("#MwDataList input[name=selectRadioGroup]:checked").closest('tr');

You can simplify your method like this

function getSelectedRowGuid() {
    return GetRowGuid(
      $("#MwDataList > input:radio[@name=selectRadioGroup]:checked :parent tr"));
}

closest() - Gets the first element that matches the selector, beginning at the current element and progressing up through the DOM tree.

As a side note, the ids of the elements should be unique on the page so try to avoid having same ids for radio buttons which I can see in your markup. If you are not going to use the ids then just remove it from the markup.

Convert bytes to int?

Lists of bytes are subscriptable (at least in Python 3.6). This way you can retrieve the decimal value of each byte individually.

>>> intlist = [64, 4, 26, 163, 255]
>>> bytelist = bytes(intlist)       # b'@x04\x1a\xa3\xff'

>>> for b in bytelist:
...    print(b)                     # 64  4  26  163  255

>>> [b for b in bytelist]           # [64, 4, 26, 163, 255]

>>> bytelist[2]                     # 26 

How to change the style of alert box?

I know this is an older post but I was looking for something similar this morning. I feel that my solution was much simpler after looking over some of the other solutions. One thing is that I use font awesome in the anchor tag.

I wanted to display an event on my calendar when the user clicked the event. So I coded a separate <div> tag like so:

<div id="eventContent" class="eventContent" style="display: none; border: 1px solid #005eb8; position: absolute; background: #fcf8e3; width: 30%; opacity: 1.0; padding: 4px; color: #005eb8; z-index: 2000; line-height: 1.1em;">
        <a style="float: right;"><i class="fa fa-times closeEvent" aria-hidden="true"></i></a><br />
        Event: <span id="eventTitle" class="eventTitle"></span><br />
        Start: <span id="startTime" class="startTime"></span><br />
        End: <span id="endTime" class="endTime"></span><br /><br />
</div>

I find it easier to use class names in my jquery since I am using asp.net.

Below is the jquery for my fullcalendar app.

<script>
    $(document).ready(function() {
        $('#calendar').fullCalendar({
            googleCalendarApiKey: 'APIkey',
            header: {
                left: 'prev,next today',
                center: 'title',
                right: 'month,agendaWeek,agendaDay'
            },
            events: {
                googleCalendarId: '@group.calendar.google.com'
            },
            eventClick: function (calEvent, jsEvent, view) {
                var stime = calEvent.start.format('MM/DD/YYYY, h:mm a');
                var etime = calEvent.end.format('MM/DD/YYYY, h:mm a');
                var eTitle = calEvent.title;
                var xpos = jsEvent.pageX;
                var ypos = jsEvent.pageY;
                $(".eventTitle").html(eTitle);
                $(".startTime").html(stime);
                $(".endTime").html(etime);
                $(".eventContent").css('display', 'block');
                $(".eventContent").css('left', '25%');
                $(".eventContent").css('top', '30%');
                return false;
            }
        });
        $(".eventContent").click(function() {
            $(".eventContent").css('display', 'none');
        });
    });
</script>

You must have your own google calendar id and api keys.

I hope this helps when you need a simple popup display.

When should static_cast, dynamic_cast, const_cast and reinterpret_cast be used?

static_cast is the first cast you should attempt to use. It does things like implicit conversions between types (such as int to float, or pointer to void*), and it can also call explicit conversion functions (or implicit ones). In many cases, explicitly stating static_cast isn't necessary, but it's important to note that the T(something) syntax is equivalent to (T)something and should be avoided (more on that later). A T(something, something_else) is safe, however, and guaranteed to call the constructor.

static_cast can also cast through inheritance hierarchies. It is unnecessary when casting upwards (towards a base class), but when casting downwards it can be used as long as it doesn't cast through virtual inheritance. It does not do checking, however, and it is undefined behavior to static_cast down a hierarchy to a type that isn't actually the type of the object.


const_cast can be used to remove or add const to a variable; no other C++ cast is capable of removing it (not even reinterpret_cast). It is important to note that modifying a formerly const value is only undefined if the original variable is const; if you use it to take the const off a reference to something that wasn't declared with const, it is safe. This can be useful when overloading member functions based on const, for instance. It can also be used to add const to an object, such as to call a member function overload.

const_cast also works similarly on volatile, though that's less common.


dynamic_cast is exclusively used for handling polymorphism. You can cast a pointer or reference to any polymorphic type to any other class type (a polymorphic type has at least one virtual function, declared or inherited). You can use it for more than just casting downwards – you can cast sideways or even up another chain. The dynamic_cast will seek out the desired object and return it if possible. If it can't, it will return nullptr in the case of a pointer, or throw std::bad_cast in the case of a reference.

dynamic_cast has some limitations, though. It doesn't work if there are multiple objects of the same type in the inheritance hierarchy (the so-called 'dreaded diamond') and you aren't using virtual inheritance. It also can only go through public inheritance - it will always fail to travel through protected or private inheritance. This is rarely an issue, however, as such forms of inheritance are rare.


reinterpret_cast is the most dangerous cast, and should be used very sparingly. It turns one type directly into another — such as casting the value from one pointer to another, or storing a pointer in an int, or all sorts of other nasty things. Largely, the only guarantee you get with reinterpret_cast is that normally if you cast the result back to the original type, you will get the exact same value (but not if the intermediate type is smaller than the original type). There are a number of conversions that reinterpret_cast cannot do, too. It's used primarily for particularly weird conversions and bit manipulations, like turning a raw data stream into actual data, or storing data in the low bits of a pointer to aligned data.


C-style cast and function-style cast are casts using (type)object or type(object), respectively, and are functionally equivalent. They are defined as the first of the following which succeeds:

  • const_cast
  • static_cast (though ignoring access restrictions)
  • static_cast (see above), then const_cast
  • reinterpret_cast
  • reinterpret_cast, then const_cast

It can therefore be used as a replacement for other casts in some instances, but can be extremely dangerous because of the ability to devolve into a reinterpret_cast, and the latter should be preferred when explicit casting is needed, unless you are sure static_cast will succeed or reinterpret_cast will fail. Even then, consider the longer, more explicit option.

C-style casts also ignore access control when performing a static_cast, which means that they have the ability to perform an operation that no other cast can. This is mostly a kludge, though, and in my mind is just another reason to avoid C-style casts.

C# getting its own class name

Get Current class name of Asp.net

string CurrentClass = System.Reflection.MethodBase.GetCurrentMethod().DeclaringType.Name.ToString();

Change Row background color based on cell value DataTable

Since datatables v1.10.18, you should specify the column key instead of index, it should be like this:

rowCallback: function(row, data, index){
            if(data["column_key"] == "ValueHere"){
                $('td', row).css('background-color', 'blue');
            }
        }

How to increase code font size in IntelliJ?

To change font size using the keyboard

In Windows or Linux press Ctrl+Shift+A

In MAC press CMD+Shift+A

In the popup frame, type Increase font size or Decrease font size, and then click Enter.

Font grows larger or smaller.

How do I get the current date and time in PHP?

According to the article How to Get Current Datetime (NOW) with PHP, there are two common ways to get the current date. To get current datetime (now) with PHP, you can use the date class with any PHP version, or better the datetime class with PHP >= 5.2.

Various date format expressions are available here.

Example using date

This expression will return NOW in format Y-m-d H:i:s.

<?php
    echo date('Y-m-d H:i:s');
?>

Example using datetime class

This expression will return NOW in format Y-m-d H:i:s.

<?php
    $dt = new DateTime();
    echo $dt->format('Y-m-d H:i:s');
?>

Windows 7, 64 bit, DLL problems

For anybody who came here, but with a Photoshop problem: my solution was to uninstall the MS VC++ redistributable first x86 and 64 both. Then install one appropriate to the Windows version and architecture (86 or 64).

How to check Django version

For Python:

import sys
sys.version

For Django (as mentioned by others here):

import django
django.get_version()

The potential problem with simply checking the version, is that versions get upgraded and so the code can go out of date. You want to make sure that '1.7' < '1.7.1' < '1.7.5' < '1.7.10'. A normal string comparison would fail in the last comparison:

>>> '1.7.5' < '1.7.10'
False

The solution is to use StrictVersion from distutils.

>>> from distutils.version import StrictVersion
>>> StrictVersion('1.7.5') < StrictVersion('1.7.10')
True

Jquery, set value of td in a table?

From:

it could be:

.html()

In an HTML document, .html() can be used to get the contents of any element.

.text()

Unlike the .html() method, .text() can be used in both XML and HTML documents. The result of the .text() method is a string containing the combined text of all matched elements.

.val()

The .val() method is primarily used to get the values of form elements such as input, select and textarea. When called on an empty collection, it returns undefined.

Gradle finds wrong JAVA_HOME even though it's correctly set

sudo ln -s /usr/lib/jvm/java-7-oracle/jre /usr/lib/jvm/default-java

Create a symbolic link to the default-java directory.

You can find your java directory by

readlink -f $(which java) 
# outputs: /usr/lib/jvm/java-7-oracle/jre/bin/java
# Remove the last `/bin/java` and use it in above symbolic link command.

What datatype should be used for storing phone numbers in SQL Server 2005?

It is always better to have separate tables for multi valued attributes like phone number.

As you have no control on source data so, you can parse the data from XML file and convert it into the proper format so that there will not be any issue with formats of a particular country and store it in a separate table so that indexing and retrieval both will be efficient.

Thank you.

How to embed a SWF file in an HTML page?

If you are using one of those js libraries to insert Flash, I suggest adding plain object embed tag inside of <noscript/>.

How do I serialize an object and save it to a file in Android?

I just made a class to handle this with Generics, so it can be used with all the object types that are serializable:

public class SerializableManager {

    /**
     * Saves a serializable object.
     *
     * @param context The application context.
     * @param objectToSave The object to save.
     * @param fileName The name of the file.
     * @param <T> The type of the object.
     */

    public static <T extends Serializable> void saveSerializable(Context context, T objectToSave, String fileName) {
        try {
            FileOutputStream fileOutputStream = context.openFileOutput(fileName, Context.MODE_PRIVATE);
            ObjectOutputStream objectOutputStream = new ObjectOutputStream(fileOutputStream);

            objectOutputStream.writeObject(objectToSave);

            objectOutputStream.close();
            fileOutputStream.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    /**
     * Loads a serializable object.
     *
     * @param context The application context.
     * @param fileName The filename.
     * @param <T> The object type.
     *
     * @return the serializable object.
     */

    public static<T extends Serializable> T readSerializable(Context context, String fileName) {
        T objectToReturn = null;

        try {
            FileInputStream fileInputStream = context.openFileInput(fileName);
            ObjectInputStream objectInputStream = new ObjectInputStream(fileInputStream);
            objectToReturn = (T) objectInputStream.readObject();

            objectInputStream.close();
            fileInputStream.close();
        } catch (IOException | ClassNotFoundException e) {
            e.printStackTrace();
        }

        return objectToReturn;
    }

    /**
     * Removes a specified file.
     *
     * @param context The application context.
     * @param filename The name of the file.
     */

    public static void removeSerializable(Context context, String filename) {
        context.deleteFile(filename);
    }

}

How to remove all ListBox items?

  • VB ListBox2.DataSource = Nothing
  • C# ListBox2.DataSource = null;

How to use readline() method in Java?

Use BufferedReader and InputStreamReader classes.

BufferedReader buffer=new BufferedReader(new InputStreamReader(System.in));
String line=buffer.readLine();

Or use java.util.Scanner class methods.

Scanner scan=new Scanner(System.in);

Is it possible to opt-out of dark mode on iOS 13?

Just add these line in info.plist file:

<key>UIUserInterfaceStyle</key>
<string>light</string>

This will force app to run in light mode only.

How to embed a video into GitHub README.md?

just to extend @GabLeRoux's answer:

[<img src="https://img.youtube.com/vi/<VIDEO ID>/maxresdefault.jpg" width="50%">](https://youtu.be/<VIDEO ID>)

this way you will be able to adjust the size of the thumbnail image in the README.md file on you Github repo.

Core dump file is not generated

Remember if you are starting the server from a service, it will start a different bash session so the ulimit won't be effective there. Try to put this in your script itself:

ulimit -c unlimited

What's the UIScrollView contentInset property for?

Great question.

Consider the following example (scroller is a UIScrollView):

float offset = 1000;
[super viewDidLoad];
for (int i=0;i<500; i++) {
    UILabel *label = [[[UILabel alloc] initWithFrame:CGRectMake(i * 100, 50, 95, 100)] autorelease];
    [label setText:[NSString stringWithFormat:@"label %d",i]];
    [self.scroller addSubview:label];
    [self.scroller setContentSize:CGSizeMake(self.view.frame.size.width * 2 + offset, 0)];
    [self.scroller setContentInset:UIEdgeInsetsMake(0, -offset, 0, 0)];
}

The insets are the ONLY way to force your scroller to have a "window" on the content where you want it. I'm still messing with this sample code, but the idea is there: use the insets to get a "window" on your UIScrollView.

Received fatal alert: handshake_failure through SSLHandshakeException

In my case, the website just can use TLSv1.2. and i use apache httpclient 4.5.6, i use this code and install jce to solve this (JDK1.7):

jce

jdk7 http://www.oracle.com/technetwork/java/javase/downloads/jce-7-download-432124.html

jdk 8 http://www.oracle.com/technetwork/java/javase/downloads/jce8-download-2133166.html

code:

SSLContext sslContext = SSLContext.getDefault();

  SSLConnectionSocketFactory sslConnectionFactory = new SSLConnectionSocketFactory(
      sslContext,
      new String[]{"TLSv1.2"}, // important
      null,
      NoopHostnameVerifier.INSTANCE);

  Registry<ConnectionSocketFactory> registry = RegistryBuilder.<ConnectionSocketFactory>create()
      .register("https", sslConnectionFactory)
      .register("http", PlainConnectionSocketFactory.INSTANCE)
      .build();

  HttpClientConnectionManager ccm = new BasicHttpClientConnectionManager(registry);
  httpclient = HttpClientBuilder.create().
      .setSSLSocketFactory(sslConnectionFactory)
      .setConnectionManager(ccm)
      .build();

How can I make IntelliJ IDEA update my dependencies from Maven?

in IntelliJ 2020 in the pom.xml view one should be able to apply pom changes by following key combination: CTRG + SHIFT + O.

And as correctly commented before - IntelliJ additionally shows a balloon widget to import changes.

WITH (NOLOCK) vs SET TRANSACTION ISOLATION LEVEL READ UNCOMMITTED

WITH (NOLOCK) is a hint on a table level. Setting the transaction isolation level to READ_UNCOMMITTED with affect the connection. The difference is in terms of scope. See READUNCOMMITTED and NOLOCK in the SQL Server documentation here:

http://technet.microsoft.com/en-us/library/ms187373.aspx

For TRANSACTION ISOLATION LEVEL: http://technet.microsoft.com/en-us/library/ms173763.aspx

Format numbers in thousands (K) in Excel

Non-Americans take note! If you use Excel with "." as 1000 separator, you need to replace the "," with a "." in the formula, such as:

[>=1000]€ #.##0." K";[<=-1000]-€ #.##0." K";0

The code above will display € 62.123 as "€ 62 K".

<ng-container> vs <template>

Edit : Now it is documented

<ng-container> to the rescue

The Angular <ng-container> is a grouping element that doesn't interfere with styles or layout because Angular doesn't put it in the DOM.

(...)

The <ng-container> is a syntax element recognized by the Angular parser. It's not a directive, component, class, or interface. It's more like the curly braces in a JavaScript if-block:

  if (someCondition) {
      statement1; 
      statement2;
      statement3;
     }

Without those braces, JavaScript would only execute the first statement when you intend to conditionally execute all of them as a single block. The <ng-container> satisfies a similar need in Angular templates.

Original answer:

According to this pull request :

<ng-container> is a logical container that can be used to group nodes but is not rendered in the DOM tree as a node.

<ng-container> is rendered as an HTML comment.

so this angular template :

<div>
    <ng-container>foo</ng-container>
<div>

will produce this kind of output :

<div>
    <!--template bindings={}-->foo
<div>

So ng-container is useful when you want to conditionaly append a group of elements (ie using *ngIf="foo") in your application but don't want to wrap them with another element.

<div>
    <ng-container *ngIf="true">
        <h2>Title</h2>
        <div>Content</div>
    </ng-container>
</div>

will then produce :

<div>
    <h2>Title</h2>
    <div>Content</div>
</div>

What do 1.#INF00, -1.#IND00 and -1.#IND mean?

From IEEE floating-point exceptions in C++ :

This page will answer the following questions.

  • My program just printed out 1.#IND or 1.#INF (on Windows) or nan or inf (on Linux). What happened?
  • How can I tell if a number is really a number and not a NaN or an infinity?
  • How can I find out more details at runtime about kinds of NaNs and infinities?
  • Do you have any sample code to show how this works?
  • Where can I learn more?

These questions have to do with floating point exceptions. If you get some strange non-numeric output where you're expecting a number, you've either exceeded the finite limits of floating point arithmetic or you've asked for some result that is undefined. To keep things simple, I'll stick to working with the double floating point type. Similar remarks hold for float types.

Debugging 1.#IND, 1.#INF, nan, and inf

If your operation would generate a larger positive number than could be stored in a double, the operation will return 1.#INF on Windows or inf on Linux. Similarly your code will return -1.#INF or -inf if the result would be a negative number too large to store in a double. Dividing a positive number by zero produces a positive infinity and dividing a negative number by zero produces a negative infinity. Example code at the end of this page will demonstrate some operations that produce infinities.

Some operations don't make mathematical sense, such as taking the square root of a negative number. (Yes, this operation makes sense in the context of complex numbers, but a double represents a real number and so there is no double to represent the result.) The same is true for logarithms of negative numbers. Both sqrt(-1.0) and log(-1.0) would return a NaN, the generic term for a "number" that is "not a number". Windows displays a NaN as -1.#IND ("IND" for "indeterminate") while Linux displays nan. Other operations that would return a NaN include 0/0, 0*8, and 8/8. See the sample code below for examples.

In short, if you get 1.#INF or inf, look for overflow or division by zero. If you get 1.#IND or nan, look for illegal operations. Maybe you simply have a bug. If it's more subtle and you have something that is difficult to compute, see Avoiding Overflow, Underflow, and Loss of Precision. That article gives tricks for computing results that have intermediate steps overflow if computed directly.

Clear data in MySQL table with PHP?

TRUNCATE TABLE mytable

Be careful with it though.

Error inflating class android.support.design.widget.NavigationView

I found solution... if you used app:srcCompat change to android:src this solution worked for me :)

What is the difference between SessionState and ViewState?

Session state is saved on the server, ViewState is saved in the page.

Session state is usually cleared after a period of inactivity from the user (no request happened containing the session id in the request cookies).

The view state is posted on subsequent post back in a hidden field.

How to set page content to the middle of screen?

I'm guessing you want to center the box both vertically and horizontally, regardless of browser window size. Since you have a fixed width and height for the box, this should work:

Markup:

<div></div>

CSS:

div {
    height: 200px;
    width: 400px;
    background: black;

    position: fixed;
    top: 50%;
    left: 50%;
    margin-top: -100px;
    margin-left: -200px;
}

The div should remain in the center of the screen even if you resize the browser. Just replace the margin-top and margin-left with half of the height and width of your table.

Edit: Credit goes to CSS-Tricks, where I got the original idea.

How can javascript upload a blob?

I was able to get @yeeking example to work by not using FormData but using javascript object to transfer the blob. Works with a sound blob created using recorder.js. Tested in Chrome version 32.0.1700.107

function uploadAudio( blob ) {
  var reader = new FileReader();
  reader.onload = function(event){
    var fd = {};
    fd["fname"] = "test.wav";
    fd["data"] = event.target.result;
    $.ajax({
      type: 'POST',
      url: 'upload.php',
      data: fd,
      dataType: 'text'
    }).done(function(data) {
        console.log(data);
    });
  };
  reader.readAsDataURL(blob);
}

Contents of upload.php

<?
// pull the raw binary data from the POST array
$data = substr($_POST['data'], strpos($_POST['data'], ",") + 1);
// decode it
$decodedData = base64_decode($data);
// print out the raw data,
$filename = $_POST['fname'];
echo $filename;
// write the data out to the file
$fp = fopen($filename, 'wb');
fwrite($fp, $decodedData);
fclose($fp);
?>

How do I ignore files in a directory in Git?

It would be the former. Go by extensions as well instead of folder structure.

I.e. my example C# development ignore file:

#OS junk files
[Tt]humbs.db
*.DS_Store

#Visual Studio files
*.[Oo]bj
*.user
*.aps
*.pch
*.vspscc
*.vssscc
*_i.c
*_p.c
*.ncb
*.suo
*.tlb
*.tlh
*.bak
*.[Cc]ache
*.ilk
*.log
*.lib
*.sbr
*.sdf
ipch/
obj/
[Bb]in
[Dd]ebug*/
[Rr]elease*/
Ankh.NoLoad

#Tooling
_ReSharper*/
*.resharper
[Tt]est[Rr]esult*

#Project files
[Bb]uild/

#Subversion files
.svn

# Office Temp Files
~$*

Update

I thought I'd provide an update from the comments below. Although not directly answering the OP's question, see the following for more examples of .gitignore syntax.

Community wiki (constantly being updated):

.gitignore for Visual Studio Projects and Solutions

More examples with specific language use can be found here (thanks to Chris McKnight's comment):

https://github.com/github/gitignore

How to find if div with specific id exists in jQuery?

You can handle it in different ways,

Objective is to check if the div exist then execute the code. Simple.

Condition:

$('#myDiv').length

Note:

#myDiv -> < div id='myDiv' > <br>
.myDiv -> < div class='myDiv' > 

This will return a number every time it is executed so if there is no div it will give a Zero [0], and as we no 0 can be represented as false in binary so you can use it in if statement. And you can you use it as a comparison with a none number. while any there are three statement given below

// Statement 0
// jQuery/Ajax has replace [ document.getElementById with $ sign ] and etc
// if you don't want to use jQuery/ajax 

   if (document.getElementById(name)) { 
      $("div#page-content div#chatbar").append("<div class='labels'>" + name + "</div><div id='" + name + "'></div>");
    }

// Statement 1
   if ($('#'+ name).length){ // if 0 then false ; if not 0 then true
       $("div#page-content div#chatbar").append("<div class='labels'>" + name + "</div><div id='" + name + "'></div>");
    }

// Statement 2
    if(!$('#'+ name).length){ // ! Means Not. So if it 0 not then [0 not is 1]
           $("div#page-content div#chatbar").append("<div class='labels'>" + name + "</div><div id='" + name + "'></div>"); 
    }
// Statement 3
    if ($('#'+ name).length > 0 ) {
      $("div#page-content div#chatbar").append("<div class='labels'>" + name + "</div><div id='" + name + "'></div>");
    }

// Statement 4
    if ($('#'+ name).length !== 0 ) { // length not equal to 0 which mean exist.
       $("div#page-content div#chatbar").append("<div class='labels'>" + name + "</div><div id='" + name + "'></div>");
    }

Steps to send a https request to a rest service in Node js

The easiest way is to use the request module.

request('https://example.com/url?a=b', function (error, response, body) {
  if (!error && response.statusCode == 200) {
    console.log(body);
  }
});

How to make the overflow CSS property work with hidden as value

Evidently, sometimes, the display properties of parent of the element containing the matter that shouldn't overflow should also be set to overflow:hidden as well, e.g.:

<div style="overflow: hidden">
  <div style="overflow: hidden">some text that should not overflow<div>
</div>

Why? I have no idea but it worked for me. See https://medium.com/@crrollyson/overflow-hidden-not-working-check-the-child-element-c33ac0c4f565 (ignore the sniping at stackoverflow!)

Java GC (Allocation Failure)

When use CMS GC in jdk1.8 will appeare this error, i change the G1 Gc solve this problem.

 -Xss512k -Xms6g -Xmx6g -XX:+UseG1GC -XX:MaxGCPauseMillis=200 -XX:InitiatingHeapOccupancyPercent=70 -XX:NewRatio=1 -XX:SurvivorRatio=6 -XX:G1ReservePercent=10 -XX:G1HeapRegionSize=32m -XX:ConcGCThreads=6 -Xloggc:gc.log -XX:+HeapDumpOnOutOfMemoryError -XX:+PrintGC -XX:+PrintGCDetails -XX:+PrintGCTimeStamps 

Print ArrayList

list.toString() is good enough.

The interface List does not define a contract for toString(), but the AbstractCollection base class provides a useful implementation that ArrayList inherits.

Post values from a multiple select

try this : here select is your select element

let select = document.getElementsByClassName('lstSelected')[0],
    options = select.options,
    len = options.length,
    data='',
    i=0;
while (i<len){
    if (options[i].selected)
        data+= "&" + select.name + '=' + options[i].value;
    i++;
}
return data;

Data is in the form of query string i.e.name=value&name=anotherValue

How to break a while loop from an if condition inside the while loop?

while(something.hasnext())
do something...
   if(contains something to process){
      do something...
      break;
   }
}

Just use the break statement;

For eg:this just prints "Breaking..."

while (true) {
     if (true) {
         System.out.println("Breaking...");
         break;
     }
     System.out.println("Did this print?");
}

Why is Thread.Sleep so harmful

For those of you who hasn't seen one valid argument against use of Thread.Sleep in SCENARIO 2, there really is one - application exit be held up by the while loop (SCENARIO 1/3 is just plain stupid so not worthy of more mentioning)

Many who pretend to be in-the-know, screaming Thread.Sleep is evil failed to mentioned a single valid reason for those of us who demanded a practical reason not to use it - but here it is, thanks to Pete - Thread.Sleep is Evil (can be easily avoided with a timer/handler)

    static void Main(string[] args)
    {
        Thread t = new Thread(new ThreadStart(ThreadFunc));
        t.Start();

        Console.WriteLine("Hit any key to exit.");
        Console.ReadLine();

        Console.WriteLine("App exiting");
        return;
    }

    static void ThreadFunc()
    {
        int i=0;
        try
        {
            while (true)
            {
                Console.WriteLine(Thread.CurrentThread.ThreadState.ToString() + " " + i);

                Thread.Sleep(1000 * 10);
                i++;
            }
        }
        finally
        {
            Console.WriteLine("Exiting while loop");
        }
        return;
    }

PHP array() to javascript array()

This may be a easy solution.

var mydate = '<?php implode("##",$youdateArray); ?>';
var ret = mydate.split("##");

How do I use boolean variables in Perl?

In Perl, the following evaluate to false in conditionals:

0
'0'
undef
''  # Empty scalar
()  # Empty list
('')

The rest are true. There are no barewords for true or false.

angularjs: ng-src equivalent for background-image:url(...)

It's also possible to do something like this with ng-style:

ng-style="image_path != '' && {'background-image':'url('+image_path+')'}"

which would not attempt to fetch a non-existing image.

Radio buttons and label to display in same line

I'm assuming the problem is that they are wrapping onto separate lines when the window is too narrow. As others have pointed out, by default the label and input should be "display:inline;", so unless you have other style rules that are changing this, they should render on the same line if there is room.

Without changing the markup, there will be no way to fix this using only CSS.

The simplest way to fix it would be to wrap the radio button and label in a block element, such as a p or a div, and then prevent that from wrapping by using white-space:nowrap. For example:

<div style="white-space:nowrap;">
  <label for="one">First Item</label>
  <input type="radio" id="one" name="first_item" value="1" />
</div>

How to prevent column break within an element?

In 2019, having this works for me on Chrome, Firefox and Opera (after many other unsuccessful attempts):

.content {
    margin: 0;
    -webkit-column-break-inside: avoid;
    break-inside: avoid;
    break-inside: avoid-column;
}

li {
    -webkit-column-break-inside:avoid;
       -moz-column-break-inside:avoid;
            column-break-inside:avoid;
           break-inside: avoid-column;
             page-break-inside: avoid;
}

How to put a horizontal divisor line between edit text's in a activity

Try this link.... horizontal rule

That should do the trick.

The code below is xml.

<View
    android:layout_width="fill_parent"
    android:layout_height="2dip"
    android:background="#FF00FF00" />

Configuring diff tool with .gitconfig

In Windows we need to run $git difftool --tool-help command to see the various options like:

    'git difftool --tool=<tool>' may be set to one of the following:
                    vimdiff
                    vimdiff2
                    vimdiff3

    The following tools are valid, but not currently available:
                    araxis
                    bc
                    bc3
                    codecompare
                    deltawalker
                    diffmerge
                    diffuse
                    ecmerge
                    emerge
                    examdiff
                    gvimdiff
                    gvimdiff2
                    gvimdiff3
                    kdiff3
                    kompare
                    meld
                    opendiff
                    p4merge
                    tkdiff
                    winmerge
                    xxdiff
Some of the tools listed above only work in a windowed
environment. If run in a terminal-only session, they will fail.

and we can add any of them(for example winmerge) like

$  git difftool --tool=winmerge

For configuring notepad++ to see files before committing:

 git config --global core.editor "'C:/Program Files/Notepad++/notepad++.exe' -multiInst -notabbar -nosession -noPlugin"

and using $ git commit will open the commit information in notepad++

How do I connect to an MDF database file?

For Visual Studio 2015 the connection string is:

"Data Source=(localdb)\MSSQLLocalDB;AttachDbFilename=|DataDirectory|Database1.mdf;Integrated Security=True"

How to get the Google Map based on Latitude on Longitude?

Have you gone through google's geocoding api. The following link shall help you get started: http://code.google.com/apis/maps/documentation/geocoding/#GeocodingRequests

How to get a pixel's x,y coordinate color from an image?

The two previous answers demonstrate how to use Canvas and ImageData. I would like to propose an answer with runnable example and using an image processing framework, so you don't need to handle the pixel data manually.

MarvinJ provides the method image.getAlphaComponent(x,y) which simply returns the transparency value for the pixel in x,y coordinate. If this value is 0, pixel is totally transparent, values between 1 and 254 are transparency levels, finally 255 is opaque.

For demonstrating I've used the image below (300x300) with transparent background and two pixels at coordinates (0,0) and (150,150).

enter image description here

Console output:

(0,0): TRANSPARENT
(150,150): NOT_TRANSPARENT

_x000D_
_x000D_
image = new MarvinImage();_x000D_
image.load("https://i.imgur.com/eLZVbQG.png", imageLoaded);_x000D_
_x000D_
function imageLoaded(){_x000D_
  console.log("(0,0): "+(image.getAlphaComponent(0,0) > 0 ? "NOT_TRANSPARENT" : "TRANSPARENT"));_x000D_
  console.log("(150,150): "+(image.getAlphaComponent(150,150) > 0 ? "NOT_TRANSPARENT" : "TRANSPARENT"));_x000D_
}
_x000D_
<script src="https://www.marvinj.org/releases/marvinj-0.7.js"></script>
_x000D_
_x000D_
_x000D_

How to open a link in new tab using angular?

Use window.open(). It's pretty straightforward !

In your component.html file-

<a (click)="goToLink("www.example.com")">page link</a>

In your component.ts file-

goToLink(url: string){
    window.open(url, "_blank");
}

Maximum number of threads in a .NET app?

Jeff Richter in CLR via C#:

"With version 2.0 of the CLR, the maximum number of worker threads default to 25 per CPU in the machine and the maximum number of I/O threads defaults to 1000. A limit of 1000 is effectively no limit at all."

Note this is based on .NET 2.0. This may have changed in .NET 3.5.

[Edit] As @Mitch pointed out, this is specific to the CLR ThreadPool. If you're creating threads directly see the @Mitch and others comments.

How to select last one week data from today's date

Yes, the syntax is accurate and it should be fine.

Here is the SQL Fiddle Demo I created for your particular case

create table sample2
(
    id int primary key,
    created_date date,
    data varchar(10)
  )

insert into sample2 values (1,'2012-01-01','testing');

And here is how to select the data

SELECT Created_Date
FROM sample2
WHERE Created_Date >= DATEADD(day,-11117, GETDATE())

Opening a folder in explorer and selecting a file

Just my 2 cents worth, if your filename contains spaces, ie "c:\My File Contains Spaces.txt", you'll need to surround the filename with quotes otherwise explorer will assume that the othe words are different arguments...

string argument = "/select, \"" + filePath +"\"";

Deploying Maven project throws java.util.zip.ZipException: invalid LOC header (bad signature)

Beyond removing .m2/repository, remove application from server, run server (without applications), stop it and add application again. Now it is supposed to work. For some reason just cleaning up server folders from interface doesn't have the same effect.

Need to find a max of three numbers in java

Two things: Change the variables x, y, z as int and call the method as Math.max(Math.max(x,y),z) as it accepts two parameters only.

In Summary, change below:

    String x = keyboard.nextLine();
    String y = keyboard.nextLine();
    String z = keyboard.nextLine();
    int max = Math.max(x,y,z);

to

    int x = keyboard.nextInt();
    int y = keyboard.nextInt();
    int z = keyboard.nextInt();
    int max =  Math.max(Math.max(x,y),z);

Assembly code vs Machine code vs Object code?

One point not yet mentioned is that there are a few different types of assembly code. In the most basic form, all numbers used in instructions must be specified as constants. For example:

$1902: BD 37 14 : LDA $1437,X
$1905: 85 03    : STA $03
$1907: 85 09    : STA $09
$1909: CA       : DEX
$190A: 10       : BPL $1902

The above bit of code, if stored at address $1900 in an Atari 2600 cartridge, will display a number of lines in different colors fetched from a table which starts at address $1437. On some tools, typing in an address, along with the rightmost part of the line above, would store to memory the values shown in the middle column, and start the next line with the following address. Typing code in that form was much more convenient than typing in hex, but one had to know the precise addresses of everything.

Most assemblers allow one to use symbolic addresses. The above code would be written more like:

rainbow_lp:
  lda ColorTbl,x
  sta WSYNC
  sta COLUBK
  dex
  bpl rainbow_lp

The assembler would automatically adjust the LDA instruction so it would refer to whatever address was mapped to the label ColorTbl. Using this style of assembler makes it much easier to write and edit code than would be possible if one had to hand-key and hand-maintain all addresses.

SHA-1 fingerprint of keystore certificate

Follow this tutorial for creating SHA1 fingerprint for Google Map v2

For Debug mode:

keytool -list -v -keystore ~/.android/debug.keystore -alias androiddebugkey -storepass android -keypass android 

for Release mode:

keytool -list -v -keystore {keystore_name} -alias {alias_name}

example:

keytool -list -v -keystore C:\Users\MG\Desktop\test.jks -alias test

On windows, when keytool command is not found, Go to your installed JDK Directory e.g. <YourJDKPath>\Java\jdk1.8.0_231\bin\, open command line and try the above commands for debug/release mode.

Another way of getting your SHA1 OR SHA-256 use ./gradlew signingReport

For more detailed info visit Using Gradle's Signing Report

How to insert &nbsp; in XSLT

I was trying to display borders on an empty cell in an HTML table. My old trick of using non-breaking space in empty cells was not working from xslt. I used line break with the same effect. I mention this just in case the reason you were trying to use the non-breaking space was to give some content to an 'empty' table cell in order to turn on the cell borders.

<br/>

C program to check little vs. big endian

This is big endian test from a configure script:

#include <inttypes.h>
int main(int argc, char ** argv){
    volatile uint32_t i=0x01234567;
    // return 0 for big endian, 1 for little endian.
    return (*((uint8_t*)(&i))) == 0x67;
}

How to set a JavaScript breakpoint from code in Chrome?

You can use debugger; within your code. If the developer console is open, execution will break. It works in firebug as well.

How do I use two submit buttons, and differentiate between which one was used to submit the form?

Give each input a name attribute. Only the clicked input's name attribute will be sent to the server.

<input type="submit" name="publish" value="Publish">
<input type="submit" name="save" value="Save">

And then

<?php
    if (isset($_POST['publish'])) {
        # Publish-button was clicked
    }
    elseif (isset($_POST['save'])) {
        # Save-button was clicked
    }
?>

Edit: Changed value attributes to alt. Not sure this is the best approach for image buttons though, any particular reason you don't want to use input[type=image]?

Edit: Since this keeps getting upvotes I went ahead and changed the weird alt/value code to real submit inputs. I believe the original question asked for some sort of image buttons but there are so much better ways to achieve that nowadays instead of using input[type=image].

Switch to another Git tag

Clone the repository as normal:

git clone git://github.com/rspec/rspec-tmbundle.git RSpec.tmbundle

Then checkout the tag you want like so:

git checkout tags/1.1.4

This will checkout out the tag in a 'detached HEAD' state. In this state, "you can look around, make experimental changes and commit them, and [discard those commits] without impacting any branches by performing another checkout".

To retain any changes made, move them to a new branch:

git checkout -b 1.1.4-jspooner

You can get back to the master branch by using:

git checkout master

Note, as was mentioned in the first revision of this answer, there is another way to checkout a tag:

git checkout 1.1.4

But as was mentioned in a comment, if you have a branch by that same name, this will result in git warning you that the refname is ambiguous and checking out the branch by default:

warning: refname 'test' is ambiguous.
Switched to branch '1.1.4'

The shorthand can be safely used if the repository does not share names between branches and tags.

Checking that a List is not empty in Hamcrest

If you're after readable fail messages, you can do without hamcrest by using the usual assertEquals with an empty list:

assertEquals(new ArrayList<>(0), yourList);

E.g. if you run

assertEquals(new ArrayList<>(0), Arrays.asList("foo", "bar");

you get

java.lang.AssertionError
Expected :[]
Actual   :[foo, bar]

Import and Export Excel - What is the best library?

I'm going to throw my hand in for flat csv files, if only because you've got the greatest control over the code. Just make sure that you read in the rows and process them one at a time (reading the document to the end and splitting will eat up all of your memory - same with writing, stream it out).

Yes, the user will have to save-as CSV in excel before you can process it, but perhaps this limitation can be overcome by training and providing clear instructions on the page?

Finally, when you export to the customer, if you set the mime type to text/csv, Excel is usually mapped to that type so it appears to the user to be 'an Excel file'.

How to detect a USB drive has been plugged in?

It is easy to check for removable devices. However, there's no guarantee that it is a USB device:

var drives = DriveInfo.GetDrives()
    .Where(drive => drive.IsReady && drive.DriveType == DriveType.Removable);

This will return a list of all removable devices that are currently accessible. More information:

Unable to cast object of type 'System.DBNull' to type 'System.String`

This is the generic method that I use to convert any object that might be a DBNull.Value:

public static T ConvertDBNull<T>(object value, Func<object, T> conversionFunction)
{
    return conversionFunction(value == DBNull.Value ? null : value);
}

usage:

var result = command.ExecuteScalar();

return result.ConvertDBNull(Convert.ToInt32);

shorter:

return command
    .ExecuteScalar()
    .ConvertDBNull(Convert.ToInt32);

Set element width or height in Standards Mode

The style property lets you specify values for CSS properties.

The CSS width property takes a length as its value.

Lengths require units. In quirks mode, browsers tend to assume pixels if provided with an integer instead of a length. Specify units.

e1.style.width = "400px";

What is the IntelliJ shortcut key to create a javadoc comment?

Shortcut Alt+Enter shows intention actions where you can choose "Add Javadoc".

Turn off warnings and errors on PHP and MySQL

You can set the type of error reporting you need in php.ini or by using the error_reporting() function on top of your script.

Read binary file as string in Ruby

If you need binary mode, you'll need to do it the hard way:

s = File.open(filename, 'rb') { |f| f.read }

If not, shorter and sweeter is:

s = IO.read(filename)

How to use multiprocessing queue in Python?

My main problem is that I really don't know how to implement multiprocessing.queue correctly, you cannot really instantiate the object for each process since they will be separate queues, how do you make sure that all processes relate to a shared queue (or in this case, queues)

This is a simple example of a reader and writer sharing a single queue... The writer sends a bunch of integers to the reader; when the writer runs out of numbers, it sends 'DONE', which lets the reader know to break out of the read loop.

from multiprocessing import Process, Queue
import time
import sys

def reader_proc(queue):
    ## Read from the queue; this will be spawned as a separate Process
    while True:
        msg = queue.get()         # Read from the queue and do nothing
        if (msg == 'DONE'):
            break

def writer(count, queue):
    ## Write to the queue
    for ii in range(0, count):
        queue.put(ii)             # Write 'count' numbers into the queue
    queue.put('DONE')

if __name__=='__main__':
    pqueue = Queue() # writer() writes to pqueue from _this_ process
    for count in [10**4, 10**5, 10**6]:             
        ### reader_proc() reads from pqueue as a separate process
        reader_p = Process(target=reader_proc, args=((pqueue),))
        reader_p.daemon = True
        reader_p.start()        # Launch reader_proc() as a separate python process

        _start = time.time()
        writer(count, pqueue)    # Send a lot of stuff to reader()
        reader_p.join()         # Wait for the reader to finish
        print("Sending {0} numbers to Queue() took {1} seconds".format(count, 
            (time.time() - _start)))

How to use a client certificate to authenticate and authorize in a Web API

Update:

Example from Microsoft:

https://docs.microsoft.com/en-us/azure/app-service/app-service-web-configure-tls-mutual-auth#special-considerations-for-certificate-validation

Original

This is how I got client certification working and checking that a specific Root CA had issued it as well as it being a specific certificate.

First I edited <src>\.vs\config\applicationhost.config and made this change: <section name="access" overrideModeDefault="Allow" />

This allows me to edit <system.webServer> in web.config and add the following lines which will require a client certification in IIS Express. Note: I edited this for development purposes, do not allow overrides in production.

For production follow a guide like this to set up the IIS:

https://medium.com/@hafizmohammedg/configuring-client-certificates-on-iis-95aef4174ddb

web.config:

<security>
  <access sslFlags="Ssl,SslNegotiateCert,SslRequireCert" />
</security>

API Controller:

[RequireSpecificCert]
public class ValuesController : ApiController
{
    // GET api/values
    public IHttpActionResult Get()
    {
        return Ok("It works!");
    }
}

Attribute:

public class RequireSpecificCertAttribute : AuthorizationFilterAttribute
{
    public override void OnAuthorization(HttpActionContext actionContext)
    {
        if (actionContext.Request.RequestUri.Scheme != Uri.UriSchemeHttps)
        {
            actionContext.Response = new HttpResponseMessage(System.Net.HttpStatusCode.Forbidden)
            {
                ReasonPhrase = "HTTPS Required"
            };
        }
        else
        {
            X509Certificate2 cert = actionContext.Request.GetClientCertificate();
            if (cert == null)
            {
                actionContext.Response = new HttpResponseMessage(System.Net.HttpStatusCode.Forbidden)
                {
                    ReasonPhrase = "Client Certificate Required"
                };

            }
            else
            {
                X509Chain chain = new X509Chain();

                //Needed because the error "The revocation function was unable to check revocation for the certificate" happened to me otherwise
                chain.ChainPolicy = new X509ChainPolicy()
                {
                    RevocationMode = X509RevocationMode.NoCheck,
                };
                try
                {
                    var chainBuilt = chain.Build(cert);
                    Debug.WriteLine(string.Format("Chain building status: {0}", chainBuilt));

                    var validCert = CheckCertificate(chain, cert);

                    if (chainBuilt == false || validCert == false)
                    {
                        actionContext.Response = new HttpResponseMessage(System.Net.HttpStatusCode.Forbidden)
                        {
                            ReasonPhrase = "Client Certificate not valid"
                        };
                        foreach (X509ChainStatus chainStatus in chain.ChainStatus)
                        {
                            Debug.WriteLine(string.Format("Chain error: {0} {1}", chainStatus.Status, chainStatus.StatusInformation));
                        }
                    }
                }
                catch (Exception ex)
                {
                    Debug.WriteLine(ex.ToString());
                }
            }

            base.OnAuthorization(actionContext);
        }
    }

    private bool CheckCertificate(X509Chain chain, X509Certificate2 cert)
    {
        var rootThumbprint = WebConfigurationManager.AppSettings["rootThumbprint"].ToUpper().Replace(" ", string.Empty);

        var clientThumbprint = WebConfigurationManager.AppSettings["clientThumbprint"].ToUpper().Replace(" ", string.Empty);

        //Check that the certificate have been issued by a specific Root Certificate
        var validRoot = chain.ChainElements.Cast<X509ChainElement>().Any(x => x.Certificate.Thumbprint.Equals(rootThumbprint, StringComparison.InvariantCultureIgnoreCase));

        //Check that the certificate thumbprint matches our expected thumbprint
        var validCert = cert.Thumbprint.Equals(clientThumbprint, StringComparison.InvariantCultureIgnoreCase);

        return validRoot && validCert;
    }
}

Can then call the API with client certification like this, tested from another web project.

[RoutePrefix("api/certificatetest")]
public class CertificateTestController : ApiController
{

    public IHttpActionResult Get()
    {
        var handler = new WebRequestHandler();
        handler.ClientCertificateOptions = ClientCertificateOption.Manual;
        handler.ClientCertificates.Add(GetClientCert());
        handler.UseProxy = false;
        var client = new HttpClient(handler);
        var result = client.GetAsync("https://localhost:44331/api/values").GetAwaiter().GetResult();
        var resultString = result.Content.ReadAsStringAsync().GetAwaiter().GetResult();
        return Ok(resultString);
    }

    private static X509Certificate GetClientCert()
    {
        X509Store store = null;
        try
        {
            store = new X509Store(StoreName.My, StoreLocation.CurrentUser);
            store.Open(OpenFlags.OpenExistingOnly | OpenFlags.ReadOnly);

            var certificateSerialNumber= "?81 c6 62 0a 73 c7 b1 aa 41 06 a3 ce 62 83 ae 25".ToUpper().Replace(" ", string.Empty);

            //Does not work for some reason, could be culture related
            //var certs = store.Certificates.Find(X509FindType.FindBySerialNumber, certificateSerialNumber, true);

            //if (certs.Count == 1)
            //{
            //    var cert = certs[0];
            //    return cert;
            //}

            var cert = store.Certificates.Cast<X509Certificate>().FirstOrDefault(x => x.GetSerialNumberString().Equals(certificateSerialNumber, StringComparison.InvariantCultureIgnoreCase));

            return cert;
        }
        finally
        {
            store?.Close();
        }
    }
}

How can I label points in this scatterplot?

Your call to text() doesn't output anything because you inverted your x and your y:

plot(abs_losses, percent_losses, 
     main= "Absolute Losses vs. Relative Losses(in%)",
     xlab= "Losses (absolute, in miles of millions)",
     ylab= "Losses relative (in % of January´2007 value)",
     col= "blue", pch = 19, cex = 1, lty = "solid", lwd = 2)

text(abs_losses, percent_losses, labels=namebank, cex= 0.7)

Now if you want to move your labels down, left, up or right you can add argument pos= with values, respectively, 1, 2, 3 or 4. For instance, to place your labels up:

 text(abs_losses, percent_losses, labels=namebank, cex= 0.7, pos=3)

enter image description here

You can of course gives a vector of value to pos if you want some of the labels in other directions (for instance for Goldman_Sachs, UBS and Société_Generale since they are overlapping with other labels):

 pos_vector <- rep(3, length(namebank))
 pos_vector[namebank %in% c("Goldman_Sachs", "Societé_Generale", "UBS")] <- 4
 text(abs_losses, percent_losses, labels=namebank, cex= 0.7, pos=pos_vector)

enter image description here

How do you do relative time in Rails?

You can use the arithmetic operators to do relative time.

Time.now - 2.days 

Will give you 2 days ago.

Viewing contents of a .jar file

Jad is klunky and no longer maintained. I've switched to "Java Decompiler", which has a slick UI and support for new language features.

Every decompiler I've used, though, runs into code it doesn't successfully decompile. For those, it helps to understand the disassembled Java byte code produced by the standard JDK tool, javap.

What are the undocumented features and limitations of the Windows FINDSTR command?

I'd like to report a bug regarding the section Source of data to search in the first answer when using en dash (–) or em dash (—) within the filename.

More specifically, if you are about to use the first option - filenames specified as arguments, the file won't be found. As soon as you use either option 2 - stdin via redirection or 3 - data stream from a pipe, findstr will find the file.

For example, this simple batch script:

echo off
chcp 1250 > nul
set INTEXTFILE1=filename with – dash.txt
set INTEXTFILE2=filename with — dash.txt

rem 3 way of findstr use with en dashed filename
echo.
echo Filename with en dash:
echo.
echo 1. As argument
findstr . "%INTEXTFILE1%"
echo.
echo 2. As stdin via redirection
findstr . < "%INTEXTFILE1%"
echo.
echo 3. As datastream from a pipe
type "%INTEXTFILE1%" | findstr .
echo.
echo.
rem The same set of operations with em dashed filename
echo Filename with em dash:
echo.
echo 1. As argument
findstr . "%INTEXTFILE2%"
echo.
echo 2. As stdin via redirection
findstr . < "%INTEXTFILE2%"
echo.
echo 3. As datastream from a pipe
type "%INTEXTFILE2%" | findstr .
echo.

pause

will print:

Filename with en dash:

  1. As argument
    FINDSTR: Cannot open filename with - dash.txt

  2. As stdin via redirection
    I am the file with an en dash.

  3. As datastream from a pipe
    I am the file with an en dash.

Filename with em dash:

  1. As argument
    FINDSTR: Cannot open filename with - dash.txt

  2. As stdin via redirection
    I am the file with an em dash.

  3. As datastream from a pipe
    I am the file with an em dash.

Hope it helps.

M.

how to use "AND", "OR" for RewriteCond on Apache?

This is an interesting question and since it isn't explained very explicitly in the documentation I'll answer this by going through the sourcecode of mod_rewrite; demonstrating a big benefit of open-source.

In the top section you'll quickly spot the defines used to name these flags:

#define CONDFLAG_NONE               1<<0
#define CONDFLAG_NOCASE             1<<1
#define CONDFLAG_NOTMATCH           1<<2
#define CONDFLAG_ORNEXT             1<<3
#define CONDFLAG_NOVARY             1<<4

and searching for CONDFLAG_ORNEXT confirms that it is used based on the existence of the [OR] flag:

else if (   strcasecmp(key, "ornext") == 0
         || strcasecmp(key, "OR") == 0    ) {
    cfg->flags |= CONDFLAG_ORNEXT;
}

The next occurrence of the flag is the actual implementation where you'll find the loop that goes through all the RewriteConditions a RewriteRule has, and what it basically does is (stripped, comments added for clarity):

# loop through all Conditions that precede this Rule
for (i = 0; i < rewriteconds->nelts; ++i) {
    rewritecond_entry *c = &conds[i];

    # execute the current Condition, see if it matches
    rc = apply_rewrite_cond(c, ctx);

    # does this Condition have an 'OR' flag?
    if (c->flags & CONDFLAG_ORNEXT) {
        if (!rc) {
            /* One condition is false, but another can be still true. */
            continue;
        }
        else {
            /* skip the rest of the chained OR conditions */
            while (   i < rewriteconds->nelts
                   && c->flags & CONDFLAG_ORNEXT) {
                c = &conds[++i];
            }
        }
    }
    else if (!rc) {
        return 0;
    }
}

You should be able to interpret this; it means that OR has a higher precedence, and your example indeed leads to if ( (A OR B) AND (C OR D) ). If you would, for example, have these Conditions:

RewriteCond A [or]
RewriteCond B [or]
RewriteCond C
RewriteCond D

it would be interpreted as if ( (A OR B OR C) and D ).

How to implement a simple scenario the OO way

You might implement your class model by composition, having the book object have a map of chapter objects contained within it (map chapter number to chapter object). Your search function could be given a list of books into which to search by asking each book to search its chapters. The book object would then iterate over each chapter, invoking the chapter.search() function to look for the desired key and return some kind of index into the chapter. The book's search() would then return some data type which could combine a reference to the book and some way to reference the data that it found for the search. The reference to the book could be used to get the name of the book object that is associated with the collection of chapter search hits.

Rails formatting date

Since I18n is the Rails core feature starting from version 2.2 you can use its localize-method. By applying the forementioned strftime %-variables you can specify the desired format under config/locales/en.yml (or whatever language), in your case like this:

time:
  formats:
    default: '%FT%T'

Or if you want to use this kind of format in a few specific places you can refer it as a variable like this

time:
  formats:
    specific_format: '%FT%T'

After that you can use it in your views like this:

l(Mode.last.created_at, format: :specific_format)  

Spring-Boot: How do I set JDBC pool properties like maximum number of connections?

In spring boot 2.x you need to reference provider specific properties.

https://docs.spring.io/spring-boot/docs/current/reference/html/boot-features-sql.html#boot-features-connect-to-production-database

The default, hikari can be set with spring.datasource.hikari.maximum-pool-size.

How to get last key in an array?

It is strange, but why this topic is not have this answer:

$lastKey = array_keys($array)[count($array)-1];

Concatenating Files And Insert New Line In Between Files

If you have few enough files that you can list each one, then you can use process substitution in Bash, inserting a newline between each pair of files:

cat File1.txt <(echo) File2.txt <(echo) File3.txt > finalfile.txt

How do I filter date range in DataTables?

Following one is working fine with moments js 2.10 and above

$.fn.dataTableExt.afnFiltering.push(
        function( settings, data, dataIndex ) {
            var min  = $('#min-date').val()
            var max  = $('#max-date').val()
            var createdAt = data[0] || 0; // Our date column in the table
            //createdAt=createdAt.split(" ");
            var startDate   = moment(min, "DD/MM/YYYY");
            var endDate     = moment(max, "DD/MM/YYYY");
            var diffDate = moment(createdAt, "DD/MM/YYYY");
            //console.log(startDate);
            if (
              (min == "" || max == "") ||
              (diffDate.isBetween(startDate, endDate))


            ) {  return true;  }
            return false;

        }
    );

Flask-SQLalchemy update a row's information

Just assigning the value and committing them will work for all the data types but JSON and Pickled attributes. Since pickled type is explained above I'll note down a slightly different but easy way to update JSONs.

class User(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    name = db.Column(db.String(80), unique=True)
    data = db.Column(db.JSON)

def __init__(self, name, data):
    self.name = name
    self.data = data

Let's say the model is like above.

user = User("Jon Dove", {"country":"Sri Lanka"})
db.session.add(user)
db.session.flush()
db.session.commit()

This will add the user into the MySQL database with data {"country":"Sri Lanka"}

Modifying data will be ignored. My code that didn't work is as follows.

user = User.query().filter(User.name=='Jon Dove')
data = user.data
data["province"] = "south"
user.data = data
db.session.merge(user)
db.session.flush()
db.session.commit()

Instead of going through the painful work of copying the JSON to a new dict (not assigning it to a new variable as above), which should have worked I found a simple way to do that. There is a way to flag the system that JSONs have changed.

Following is the working code.

from sqlalchemy.orm.attributes import flag_modified
user = User.query().filter(User.name=='Jon Dove')
data = user.data
data["province"] = "south"
user.data = data
flag_modified(user, "data")
db.session.merge(user)
db.session.flush()
db.session.commit()

This worked like a charm. There is another method proposed along with this method here Hope I've helped some one.

How can I import Swift code to Objective-C?

Importing Swift file inside Objective-c can cause this error, if it doesn't import properly.

NOTE: You don't have to import Swift files externally, you just have to import one file which takes care of swift files.

When you Created/Copied Swift file inside Objective-C project. It would've created a bridging header automatically.

Check Objective-C Generated Interface Header Name at Targets -> Build Settings.

enter image description here

Based on above, I will import KJExpandable-Swift.h as it is.

Your's will be TargetName-Swift.h, Where TargetName differs based on your project name or another target your might have added and running on it.

As below my target is KJExpandable, so it's KJExpandable-Swift.h
enter image description here

Insert new item in array on any position in PHP

Solution by jay.lee is perfect. In case you want to add item(s) to a multidimensional array, first add a single dimensional array and then replace it afterwards.

$original = (
[0] => Array
    (
        [title] => Speed
        [width] => 14
    )

[1] => Array
    (
        [title] => Date
        [width] => 18
    )

[2] => Array
    (
        [title] => Pineapple
        [width] => 30
     )
)

Adding an item in same format to this array will add all new array indexes as items instead of just item.

$new = array(
    'title' => 'Time',
    'width' => 10
);
array_splice($original,1,0,array('random_string')); // can be more items
$original[1] = $new;  // replaced with actual item

Note: Adding items directly to a multidimensional array with array_splice will add all its indexes as items instead of just that item.

How to wait in bash for several subprocesses to finish and return exit code !=0 when any subprocess ends with code !=0?

Here's what I've come up with so far. I would like to see how to interrupt the sleep command if a child terminates, so that one would not have to tune WAITALL_DELAY to one's usage.

waitall() { # PID...
  ## Wait for children to exit and indicate whether all exited with 0 status.
  local errors=0
  while :; do
    debug "Processes remaining: $*"
    for pid in "$@"; do
      shift
      if kill -0 "$pid" 2>/dev/null; then
        debug "$pid is still alive."
        set -- "$@" "$pid"
      elif wait "$pid"; then
        debug "$pid exited with zero exit status."
      else
        debug "$pid exited with non-zero exit status."
        ((++errors))
      fi
    done
    (("$#" > 0)) || break
    # TODO: how to interrupt this sleep when a child terminates?
    sleep ${WAITALL_DELAY:-1}
   done
  ((errors == 0))
}

debug() { echo "DEBUG: $*" >&2; }

pids=""
for t in 3 5 4; do 
  sleep "$t" &
  pids="$pids $!"
done
waitall $pids

How to Verify if file exist with VB script

There is no built-in functionality in VBS for that, however, you can use the FileSystemObject FileExists function for that :

Option Explicit
DIM fso    
Set fso = CreateObject("Scripting.FileSystemObject")

If (fso.FileExists("C:\Program Files\conf")) Then
  WScript.Echo("File exists!")
  WScript.Quit()
Else
  WScript.Echo("File does not exist!")
End If

WScript.Quit()

How to insert a line break <br> in markdown

Try adding 2 spaces (or a backslash \) after the first line:

[Name of link](url)
My line of text\

Visually:

[Name of link](url)<space><space>
My line of text\

Output:

<p><a href="url">Name of link</a><br>
My line of text<br></p>

Best HTTP Authorization header type for JWT

Short answer

The Bearer authentication scheme is what you are looking for.

Long answer

Is it related to bears?

Errr... No :)

According to the Oxford Dictionaries, here's the definition of bearer:

bearer /'b??r?/
noun

  1. A person or thing that carries or holds something.

  2. A person who presents a cheque or other order to pay money.

The first definition includes the following synonyms: messenger, agent, conveyor, emissary, carrier, provider.

And here's the definition of bearer token according to the RFC 6750:

1.2. Terminology

Bearer Token

A security token with the property that any party in possession of the token (a "bearer") can use the token in any way that any other party in possession of it can. Using a bearer token does not require a bearer to prove possession of cryptographic key material (proof-of-possession).

The Bearer authentication scheme is registered in IANA and originally defined in the RFC 6750 for the OAuth 2.0 authorization framework, but nothing stops you from using the Bearer scheme for access tokens in applications that don't use OAuth 2.0.

Stick to the standards as much as you can and don't create your own authentication schemes.


An access token must be sent in the Authorization request header using the Bearer authentication scheme:

2.1. Authorization Request Header Field

When sending the access token in the Authorization request header field defined by HTTP/1.1, the client uses the Bearer authentication scheme to transmit the access token.

For example:

GET /resource HTTP/1.1
Host: server.example.com
Authorization: Bearer mF_9.B5f-4.1JqM

[...]

Clients SHOULD make authenticated requests with a bearer token using the Authorization request header field with the Bearer HTTP authorization scheme. [...]

In case of invalid or missing token, the Bearer scheme should be included in the WWW-Authenticate response header:

3. The WWW-Authenticate Response Header Field

If the protected resource request does not include authentication credentials or does not contain an access token that enables access to the protected resource, the resource server MUST include the HTTP WWW-Authenticate response header field [...].

All challenges defined by this specification MUST use the auth-scheme value Bearer. This scheme MUST be followed by one or more auth-param values. [...].

For example, in response to a protected resource request without authentication:

HTTP/1.1 401 Unauthorized
WWW-Authenticate: Bearer realm="example"

And in response to a protected resource request with an authentication attempt using an expired access token:

HTTP/1.1 401 Unauthorized
WWW-Authenticate: Bearer realm="example",
                         error="invalid_token",
                         error_description="The access token expired"

Get a CSS value with JavaScript

As a matter of safety, you may wish to check that the element exists before you attempt to read from it. If it doesn't exist, your code will throw an exception, which will stop execution on the rest of your JavaScript and potentially display an error message to the user -- not good. You want to be able to fail gracefully.

var height, width, top, margin, item;
item = document.getElementById( "image_1" );
if( item ) {
  height = item.style.height;
  width = item.style.width;
  top = item.style.top;
  margin = item.style.margin;
} else {
  // Fail gracefully here
}

Remove all constraints affecting a UIView

You could use something like this:

[viewA.superview.constraints enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {
    NSLayoutConstraint *constraint = (NSLayoutConstraint *)obj;
    if (constraint.firstItem == viewA || constraint.secondItem == viewA) {
        [viewA.superview removeConstraint:constraint];
    }
}];

[viewA removeConstraints:viewA.constraints];

Basically, this is enumerates over all the constraints on the superview of viewA and removes all of the constraints that are related to viewA.

Then, the second part removes the constraints from viewA using the array of viewA's constraints.

Returning anonymous type in C#

Three options:

Option1:

public class TheRepresentativeType {
    public ... SomeVariable {get;set;}
    public ... AnotherVariable {get;set;}
}

public IEnumerable<TheRepresentativeType> TheMethod(SomeParameter)
{
   using (MyDC TheDC = new MyDC())
   {
     var TheQueryFromDB = (....
                           select new TheRepresentativeType{ SomeVariable = ....,
                                        AnotherVariable = ....}
                           ).ToList();

     return TheQueryFromDB;
   } 
}

Option 2:

public IEnumerable TheMethod(SomeParameter)
{
   using (MyDC TheDC = new MyDC())
   {
     var TheQueryFromDB = (....
                           select new TheRepresentativeType{ SomeVariable = ....,
                                        AnotherVariable = ....}
                           ).ToList();
     return TheQueryFromDB;
   } 
}

you can iterate it as object

Option 3:

public IEnumerable<dynamic> TheMethod(SomeParameter)
{
   using (MyDC TheDC = new MyDC())
   {
     var TheQueryFromDB = (....
                           select new TheRepresentativeType{ SomeVariable = ....,
                                        AnotherVariable = ....}
                           ).ToList();

     return TheQueryFromDB; //You may need to call .Cast<dynamic>(), but I'm not sure
   } 
}

and you will be able to iterate it as a dynamic object and access their properties directly

moving committed (but not pushed) changes to a new branch after pull

What about:

  1. Branch from the current HEAD.
  2. Make sure you are on master, not your new branch.
  3. git reset back to the last commit before you started making changes.
  4. git pull to re-pull just the remote changes you threw away with the reset.

Or will that explode when you try to re-merge the branch?

installing requests module in python 2.7 windows

  1. Download the source code(zip or rar package).
  2. Run the setup.py inside.

Upload file to FTP using C#

Easiest way

The most trivial way to upload a file to an FTP server using .NET framework is using WebClient.UploadFile method:

WebClient client = new WebClient();
client.Credentials = new NetworkCredential("username", "password");
client.UploadFile("ftp://ftp.example.com/remote/path/file.zip", @"C:\local\path\file.zip");

Advanced options

If you need a greater control, that WebClient does not offer (like TLS/SSL encryption, ascii/text transfer mode, active mode, transfer resuming, progress monitoring, etc), use FtpWebRequest. Easy way is to just copy a FileStream to an FTP stream using Stream.CopyTo:

FtpWebRequest request =
    (FtpWebRequest)WebRequest.Create("ftp://ftp.example.com/remote/path/file.zip");
request.Credentials = new NetworkCredential("username", "password");
request.Method = WebRequestMethods.Ftp.UploadFile;  

using (Stream fileStream = File.OpenRead(@"C:\local\path\file.zip"))
using (Stream ftpStream = request.GetRequestStream())
{
    fileStream.CopyTo(ftpStream);
}

Progress monitoring

If you need to monitor an upload progress, you have to copy the contents by chunks yourself:

FtpWebRequest request =
    (FtpWebRequest)WebRequest.Create("ftp://ftp.example.com/remote/path/file.zip");
request.Credentials = new NetworkCredential("username", "password");
request.Method = WebRequestMethods.Ftp.UploadFile;  

using (Stream fileStream = File.OpenRead(@"C:\local\path\file.zip"))
using (Stream ftpStream = request.GetRequestStream())
{
    byte[] buffer = new byte[10240];
    int read;
    while ((read = fileStream.Read(buffer, 0, buffer.Length)) > 0)
    {
        ftpStream.Write(buffer, 0, read);
        Console.WriteLine("Uploaded {0} bytes", fileStream.Position);
    } 
}

For GUI progress (WinForms ProgressBar), see C# example at:
How can we show progress bar for upload with FtpWebRequest


Uploading folder

If you want to upload all files from a folder, see
Upload directory of files to FTP server using WebClient.

For a recursive upload, see
Recursive upload to FTP server in C#

Multiple separate IF conditions in SQL Server

IF you are checking one variable against multiple condition then you would use something like this Here the block of code where the condition is true will be executed and other blocks will be ignored.

IF(@Var1 Condition1)
     BEGIN
      /*Your Code Goes here*/
     END

ELSE IF(@Var1 Condition2)
      BEGIN
        /*Your Code Goes here*/ 
      END 

    ELSE      --<--- Default Task if none of the above is true
     BEGIN
       /*Your Code Goes here*/
     END

If you are checking conditions against multiple variables then you would have to go for multiple IF Statements, Each block of code will be executed independently from other blocks.

IF(@Var1 Condition1)
 BEGIN
   /*Your Code Goes here*/
 END


IF(@Var2 Condition1)
 BEGIN
   /*Your Code Goes here*/
 END


IF(@Var3 Condition1)
 BEGIN
   /*Your Code Goes here*/
 END

After every IF statement if there are more than one statement being executed you MUST put them in BEGIN..END Block. Anyway it is always best practice to use BEGIN..END blocks

Update

Found something in your code some BEGIN END you are missing

ELSE IF(@ID IS NOT NULL AND @ID in (SELECT ID FROM Places))   -- Outer Most Block ELSE IF
BEGIN   
     SELECT @MyName = Name ...  
    ...Some stuff....                       
    IF(SOMETHNG_1)         -- IF
                 --BEGIN
        BEGIN TRY               
            UPDATE ....                                                                 
        END TRY

        BEGIN CATCH
            SELECT ERROR_MESSAGE() AS 'Message' 
            RETURN -1
        END CATCH
                -- END
    ELSE IF(SOMETHNG_2)    -- ELSE IF
                 -- BEGIN
        BEGIN TRY
            UPDATE ...                                                      
        END TRY
        BEGIN CATCH
            SELECT ERROR_MESSAGE() AS 'Message' 
            RETURN -1
        END CATCH   
               -- END
    ELSE                  -- ELSE
        BEGIN
            BEGIN TRY
                UPDATE ...                                                              
            END TRY
            BEGIN CATCH
                SELECT ERROR_MESSAGE() AS 'Message' 
                RETURN -1
            END CATCH   
         END             
      --The above works I then insert this below and these if statement become nested----
          IF(@A!= @SA)
            BEGIN
             exec Store procedure 
                    @FIELD = 15,
                    ... more params...
            END                 
        IF(@S!= @SS)
          BEGIN
             exec Store procedure 
                    @FIELD = 10,
                    ... more params...

SQLite Query in Android to count rows

int nombr = 0;
Cursor cursor = sqlDatabase.rawQuery("SELECT column FROM table WHERE column = Value", null);
nombr = cursor.getCount();

C++, copy set to vector

Just use the constructor for the vector that takes iterators:

std::set<T> s;

//...

std::vector v( s.begin(), s.end() );

Assumes you just want the content of s in v, and there's nothing in v prior to copying the data to it.

How to force R to use a specified factor level as reference in a regression?

The relevel() command is a shorthand method to your question. What it does is reorder the factor so that whatever is the ref level is first. Therefore, reordering your factor levels will also have the same effect but gives you more control. Perhaps you wanted to have levels 3,4,0,1,2. In that case...

bFactor <- factor(b, levels = c(3,4,0,1,2))

I prefer this method because it's easier for me to see in my code not only what the reference was but the position of the other values as well (rather than having to look at the results for that).

NOTE: DO NOT make it an ordered factor. A factor with a specified order and an ordered factor are not the same thing. lm() may start to think you want polynomial contrasts if you do that.

wget ssl alert handshake failure

You probably have an old version of wget. I suggest installing wget using Chocolatey, the package manager for Windows. This should give you a more recent version (if not the latest).

Run this command after having installed Chocolatey (as Administrator):

choco install wget

Getting error while sending email through Gmail SMTP - "Please log in via your web browser and then try again. 534-5.7.14"

There are two ways to resolve this, and only one may work, depending on how you're accessing Google.

The first method is to authorize access for your IP or client machine using the https://accounts.google.com/DisplayUnlockCaptcha link. That can resolve authentication issues on client devices, like mobile or desktop apps. I would test this first, because it results in a lower overall decrease in account security.

If the above link doesn't work, it's because the session is being initiated by an app or device that is not associated with your particular location. Examples include:

  • An app that uses a remote server to retrieve data, like a web site or, in my case, other Google servers
  • A company mail server fetching mail on your behalf

In all such cases you have to use the https://www.google.com/settings/security/lesssecureapps link referenced above.

TLDR; check the captcha link first, and if it doesn't work, try the other one and enable less secure apps.

jQuery: Setting select list 'selected' based on text, failing strangely

If you want to selected value on drop-down text bases so you should use below changes: Here below is example and country name is dynamic:

    <select id="selectcountry">
    <option value="1">India</option>
    <option value="2">Ireland</option>
    </select>
    <script>
     var country_name ='India'
     $('#selectcountry').find('option:contains("' + country_name + '")').attr('selected', 'selected');
    </script>

How do I refresh the page in ASP.NET? (Let it reload itself by code)

This might be late, but I hope it helps someone who is looking for the answer.

You can use the following line to do that:

Server.TransferRequest(Request.Url.AbsolutePath, false);

Try to avoid using Response.Redirect as it increases the steps in the process. What it actually does is:

  1. Sends back the page with redirection header
  2. The Browser redirects to the destination URL.

As you can see, the same outcome takes 2 trips rather than 1 trip.

JPA COUNT with composite primary key query not working

Use count(d.ertek) or count(d.id) instead of count(d). This can be happen when you have composite primary key at your entity.

What is the => assignment in C# in a property signature

Ok... I made a comment that they were different but couldn't explain exactly how but now I know.

String Property { get; } = "value";

is not the same as

String Property => "value";

Here's the difference...

When you use the auto initializer the property creates the instance of value and uses that value persistently. In the above post there is a broken link to Bill Wagner, that explains this well, and I searched the correct link to understand it myself.

In my situation I had my property auto initialize a command in a ViewModel for a View. I changed the property to use expression bodied initializer and the command CanExecute stopped working.

Here's what it looked like and here's what was happening.

Command MyCommand { get; } = new Command();  //works

here's what I changed it to.

Command MyCommand => new Command();  //doesn't work properly

The difference here is when I use { get; } = I create and reference the SAME command in that property. When I use => I actually create a new command and return it every time the property is called. Therefore, I could never update the CanExecute on my command because I was always telling it to update a new reference of that command.

{ get; } = // same reference
=>         // new reference

All that said, if you are just pointing to a backing field then it works fine. This only happens when the auto or expression body creates the return value.

Limit the output of the TOP command to a specific process name

I came here looking for the answer to this on OSX. I ended up getting what I wanted with bash and awk:

topfiltered() {
  [[ -z "$1" ]] && return
  dump="/tmp/top_dump"
  rm -f "$dump"
  while :; do
    clear
    [[ -s "$dump" ]] && head -n $(( $LINES - 1 )) "$dump"
    top -l 1 -o cpu -ncols $(( $COLUMNS / 8 )) | awk -v p="$(pgrep -d ' ' $@)" '
        BEGIN { split(p, arr); for (k in arr) pids[arr[k]]=1 }
        NR<=12 || ($1 in pids)
    ' >"$dump"
  done
}

I loop top in logging mode and filter it with awk, building an associative array from the output of pgrep. Awk prints the first 12 lines, where line 12 is the column headers, and then every line which has a pid that's a key in the array. The dump file is used for a more watchable loop.

How to create virtual column using MySQL SELECT?

Try this one if you want to create a virtual column "age" within a select statement:

select brand, name, "10" as age from cars...

Byte Array in Python

Dietrich's answer is probably just the thing you need for what you describe, sending bytes, but a closer analogue to the code you've provided for example would be using the bytearray type.

>>> key = bytearray([0x13, 0x00, 0x00, 0x00, 0x08, 0x00])
>>> bytes(key)
b'\x13\x00\x00\x00\x08\x00'
>>> 

How can a file be copied?

For large files, what I did was read the file line by line and read each line into an array. Then, once the array reached a certain size, append it to a new file.

for line in open("file.txt", "r"):
    list.append(line)
    if len(list) == 1000000: 
        output.writelines(list)
        del list[:]

Searching a string in eclipse workspace

Press Ctrl+shift+L and type your string

How to iterate through range of Dates in Java?

We can migrate the logic to various methods foe Java 7, Java 8 and Java 9:

public static List<Date> getDatesRangeJava7(Date startDate, Date endDate) {
    List<Date> datesInRange = new ArrayList<>();
    Calendar startCalendar = new GregorianCalendar();
    startCalendar.setTime(startDate);
    Calendar endCalendar = new GregorianCalendar();
    endCalendar.setTime(endDate);
    while (startCalendar.before(endCalendar)) {
        Date result = startCalendar.getTime();
        datesInRange.add(result);
        startCalendar.add(Calendar.DATE, 1);
    }
    return datesInRange;
}

public static List<LocalDate> getDatesRangeJava8(LocalDate startDate, LocalDate endDate) {
    int numOfDays = (int) ChronoUnit.DAYS.between(startDate, endDate);
    return IntStream.range(0, numOfDays)
            .mapToObj(startDate::plusDays)
            .collect(Collectors.toList());
}

public static List<LocalDate> getDatesRangeJava9(LocalDate startDate, LocalDate endDate) {
    return startDate.datesUntil(endDate).collect(Collectors.toList());
}

Then we can invoke these methods as:

SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd");
Date startDate = formatter.parse("2010-12-20");
Date endDate = formatter.parse("2010-12-26");
List<Date> dateRangeList = getDatesRangeJava7(startDate, endDate);
System.out.println(dateRangeList);

LocalDate startLocalDate = startDate.toInstant().atZone(ZoneId.systemDefault()).toLocalDate();
LocalDate endLocalDate = endDate.toInstant().atZone(ZoneId.systemDefault()).toLocalDate();
List<LocalDate> dateRangeList8 = getDatesRangeJava8(startLocalDate, endLocalDate);
System.out.println(dateRangeList8);
List<LocalDate> dateRangeList9 = getDatesRangeJava8(startLocalDate, endLocalDate);
System.out.println(dateRangeList9);

The output would be:

[Mon Dec 20 00:00:00 IST 2010, Tue Dec 21 00:00:00 IST 2010, Wed Dec 22 00:00:00 IST 2010, Thu Dec 23 00:00:00 IST 2010, Fri Dec 24 00:00:00 IST 2010, Sat Dec 25 00:00:00 IST 2010]

[2010-12-20, 2010-12-21, 2010-12-22, 2010-12-23, 2010-12-24, 2010-12-25]

[2010-12-20, 2010-12-21, 2010-12-22, 2010-12-23, 2010-12-24, 2010-12-25]

How can I use external JARs in an Android project?

Yes, you can use it. Here is how:

  1. Your Project -> right click -> Import -> File System -> yourjar.jar
  2. Your Project -> right click -> Properties -> Java Build Path -> Libraries -> Add Jar -> yourjar.jar

This video might be useful in case you are having some issues.

Dynamically adding HTML form field using jQuery

something like so might work:

<script type="text/javascript">
$(document).ready(function(){
    var $input = $("<input name='myField' type='text'>");
    $('#section2').append($input);
});
</script>

<form>
    <div id="section1"><!-- some controls--></div>
    <div id="section2"><!-- for dynamic controls--></div>
</form>

Difference between SurfaceView and View?

A SurfaceView is a custom view in Android that can be used to drawn inside it.

The main difference between a View and a SurfaceView is that a View is drawn in the UI Thread, which is used for all the user interaction.

If you want to update the UI rapidly enough and render a good amount of information in it, a SurfaceView is a better choice.

But there are a few technical insides to the SurfaceView:

1. They are not hardware accelerated.

2. Normal views are rendered when you call the methods invalidate or postInvalidate(), but this does not mean the view will be immediately updated (A VSYNC will be sent, and the OS decides when it gets updated. The SurfaceView can be immediately updated.

3. A SurfaceView has an allocated surface buffer, so it is more costly

if statement in ng-click

Here's a hack I discovered that might work for you, although its not pretty and I'd personally be embarrassed to use such a line of code:

ng-click="profileForm.$valid ? updateMyProfile() : alert('failed')"

Now, you must be thinking 'but I don't want it to alert("failed") if my profileForm isn't valid. Well that's the ugly part. For me, no matter what I put in the else clause of this ternary statement doesn't get executed ever.

Yet if its removed an error is thrown. So you can just stuff it with a pointless alert.
I told you it was ugly... but I don't even get any errors when I do something like this.
The proper way to do this is as Chen-Tsu mentioned, but to each their own.

How to get full REST request body using Jersey?

Turns out you don't have to do much at all.

See below - the parameter x will contain the full HTTP body (which is XML in our case).

@POST
public Response go(String x) throws IOException {
    ...
}

Python Script to convert Image into Byte array

Use bytearray:

with open("img.png", "rb") as image:
  f = image.read()
  b = bytearray(f)
  print b[0]

You can also have a look at struct which can do many conversions of that kind.

What is the difference between WCF and WPF?

  • WPF is your FrontEnd (presentation: .htm, .xaml & .css, ..)
  • WCF is your BackEnd app (services that involve server connections to acquire data for you to deliver to the FrontEnd to present). You can write WCF for RESTful model.
  • WebAPI is for building services of RESTful model for 4.+ frameworks.

How do I write a backslash (\) in a string?

The backslash ("\") character is a special escape character used to indicate other special characters such as new lines (\n), tabs (\t), or quotation marks (\").

If you want to include a backslash character itself, you need two backslashes or use the @ verbatim string:

var s = "\\Tasks";
// or 
var s = @"\Tasks";

Read the MSDN documentation/C# Specification which discusses the characters that are escaped using the backslash character and the use of the verbatim string literal.

Generally speaking, most C# .NET developers tend to favour using the @ verbatim strings when building file/folder paths since it saves them from having to write double backslashes all the time and they can directly copy/paste the path, so I would suggest that you get in the habit of doing the same.


That all said, in this case, I would actually recommend you use the Path.Combine utility method as in @lordkain's answer as then you don't need to worry about whether backslashes are already included in the paths and accidentally doubling-up the slashes or omitting them altogether when combining parts of paths.

XML serialization in Java?

Usually I use jaxb or XMLBeans if I need to create objects serializable to XML. Now, I can see that XStream might be very useful as it's nonintrusive and has really simple api. I'll play with it soon and probably use it. The only drawback I noticed is that I can't create object's id on my own for cross referencing.

@Barak Schiller
Thanks for posting link to XStream!

Pass array to mvc Action via AJAX

You need to convert Array to string :

//arrayOfValues = [1, 2, 3];  
$.get('/controller/MyAction', { arrayOfValues: "1, 2, 3" }, function (data) {...

this works even in form of int, long or string

public ActionResult MyAction(int[] arrayOfValues )

WPF button click in C# code

The following should do the trick:

btn.Click += btn1_Click;

How do you install and run Mocha, the Node.js testing module? Getting "mocha: command not found" after install

For windows :

Package.json

  "scripts": {
    "start": "nodemon app.js",
    "test": "mocha"
  },

then run the command

npm run test

How do I extract Month and Year in a MySQL date and compare them?

While it was discussed in the comments, there isn't an answer containing it yet, so it can be easy to miss. DATE_FORMAT works really well and is flexible to handle many different patterns.

DATE_FORMAT(date,'%Y%m')

To put it in a query:

SELECT DATE_FORMAT(test_date,'%Y%m') AS date FROM test_table;

Using arrays or std::vectors in C++, what's the performance gap?

STL is a heavily optimized library. In fact, it's even suggested to use STL in games where high performance might be needed. Arrays are too error prone to be used in day to day tasks. Today's compilers are also very smart and can really produce excellent code with STL. If you know what you are doing, STL can usually provide the necessary performance. For example by initializing vectors to required size (if you know from start), you can basically achieve the array performance. However, there might be cases where you still need arrays. When interfacing with low level code (i.e. assembly) or old libraries that require arrays, you might not be able to use vectors.

What's the difference between OpenID and OAuth?

At finally OAuth gives you back the access token to access the resource from resource server, OpenID gives you back meta data details about resources in JWT / encrypted token

C#: New line and tab characters in strings

sb.Append(Environment.Newline);
sb.Append("\t");

jQuery - hashchange event

try Mozilla official site: https://developer.mozilla.org/en/DOM/window.onhashchange

cite as follow:

if ("onhashchange" in window) {
    alert("The browser supports the hashchange event!");
}

function locationHashChanged() {
    if (location.hash === "#somecoolfeature") {
        somecoolfeature();
    }
}

window.onhashchange = locationHashChanged;