Programs & Examples On #Nfsclient

Force unmount of NFS-mounted directory

Couldn't find a working answer here; but on linux you can run "umount.nfs4 /volume -f" and it definitely unmounts it.

ngOnInit not being called when Injectable class is Instantiated

import {Injectable, OnInit} from 'angular2/core';
import { RestApiService, RestRequest } from './rest-api.service';
import {Service} from "path/to/service/";

export class MovieDbService implements OnInit {


constructor(private _movieDbRest: RestApiService,
            private instanceMyService : Service ){

   // do evreything like OnInit just on services


   this.userId = this.instanceMyService.getUserId()


Scala check if element is present in a list

Even easier!

strings contains myString

How to check whether a int is not null or empty?

I think you can initialize the variables a value like -1, because if the int type variables is not initialized it can't be used. When you want to check if it is not the value you want you can check if it is -1.

Do sessions really violate RESTfulness?

HTTP transaction, basic access authentication, is not suitable for RBAC, because basic access authentication uses the encrypted username:password every time to identify, while what is needed in RBAC is the Role the user wants to use for a specific call. RBAC does not validate permissions on username, but on roles.

You could tric around to concatenate like this: usernameRole:password, but this is bad practice, and it is also inefficient because when a user has more roles, the authentication engine would need to test all roles in concatenation, and that every call again. This would destroy one of the biggest technical advantages of RBAC, namely a very quick authorization-test.

So that problem cannot be solved using basic access authentication.

To solve this problem, session-maintaining is necessary, and that seems, according to some answers, in contradiction with REST.

That is what I like about the answer that REST should not be treated as a religion. In complex business cases, in healthcare, for example, RBAC is absolutely common and necessary. And it would be a pity if they would not be allowed to use REST because all REST-tools designers would treat REST as a religion.

For me there are not many ways to maintain a session over HTTP. One can use cookies, with a sessionId, or a header with a sessionId.

If someone has another idea I will be glad to hear it.

git: fatal unable to auto-detect email address

Problem solved after I run those commands with sudo

How to go to a specific element on page?


Same thing, but wrapping it in a function:

function scrollIntoView(eleID) {
   var e = document.getElementById(eleID);
   if (!!e && e.scrollIntoView) {

This even works in an IFrame on an iPhone.

Example of using getElementById:

Jquery click not working with ipad

I found that when I made my binding more specific, it began to work on iOS. I had:

$(document).on('click tap', 'span.clickable', function(e){ ... });

When I changed it to:

$("div.content").on('click tap', 'span.clickable', function(e){ ... });

iOS began responding.

Abort a Git Merge

Truth be told there are many, many resources explaining how to do this already out on the web:

Git: how to reverse-merge a commit?

Git: how to reverse-merge a commit?

Undoing Merges, from Git's blog (retrieved from's Wayback Machine)

So I guess I'll just summarize some of these:

  1. git revert <merge commit hash>
    This creates an extra "revert" commit saying you undid a merge

  2. git reset --hard <commit hash *before* the merge>
    This reset history to before you did the merge. If you have commits after the merge you will need to cherry-pick them on to afterwards.

But honestly this guide here is better than anything I can explain, with diagrams! :)

I just assigned a variable, but echo $variable shows something else

echo $var output highly depends on the value of IFS variable. By default it contains space, tab, and newline characters:

[ks@localhost ~]$ echo -n "$IFS" | cat -vte

This means that when shell is doing field splitting (or word splitting) it uses all these characters as word separators. This is what happens when referencing a variable without double quotes to echo it ($var) and thus expected output is altered.

One way to prevent word splitting (besides using double quotes) is to set IFS to null. See :

If the value of IFS is null, no field splitting shall be performed.

Setting to null means setting to empty value:



[ks@localhost ~]$ echo -n "$IFS" | cat -vte
[ks@localhost ~]$ var=$'key\nvalue'
[ks@localhost ~]$ echo $var
key value
[ks@localhost ~]$ IFS=
[ks@localhost ~]$ echo $var
[ks@localhost ~]$ 

How to check if "Radiobutton" is checked?

radioButton.isChecked() function returns true if the Radion button is chosen, false otherwise.


How to add image to canvas

You need to wait until the image is loaded before you draw it. Try this instead:

var canvas = document.getElementById('viewport'),
context = canvas.getContext('2d');


function make_base()
  base_image = new Image();
  base_image.src = 'img/base.png';
  base_image.onload = function(){
    context.drawImage(base_image, 0, 0);

i.e. draw the image in the onload callback of the image.

What's the difference between <mvc:annotation-driven /> and <context:annotation-config /> in servlet?

There is also some more detail on the use of <mvc:annotation-driven /> in the Spring docs. In a nutshell, <mvc:annotation-driven /> gives you greater control over the inner workings of Spring MVC. You don't need to use it unless you need one or more of the features outlined in the aforementioned section of the docs.

Also, there are other "annotation-driven" tags available to provide additional functionality in other Spring modules. For example, <transaction:annotation-driven /> enables the use of the @Transaction annotation, <task:annotation-driven /> is required for @Scheduled et al...

Python locale error: unsupported locale setting

For those deploying a docker image and using a locale that isn't shown in the locale -a command, add this line to your Dockerfile
RUN apt-get install -y locales

This should add all locales to your image, I used de_DE which is not part of AWS default Ubuntu server.

how to check the dtype of a column in python pandas

If you want to mark the type of a dataframe column as a string, you can do:


An example:

In [8]: df = pd.DataFrame([[1,'a',1.2],[2,'b',2.3]])
In [9]: df[0].dtype.kind, df[1].dtype.kind, df[2].dtype.kind
Out[9]: ('i', 'O', 'f')

The answer for your code:

for y in agg.columns:
    if(agg[y].dtype.kind == 'f' or agg[y].dtype.kind == 'i'):


Forcing a postback

You can manually call the method invoked by PostBack from the Page_Load event:

public void Page_Load(object sender, EventArgs e)
    MyPostBackMethod(sender, e);

But if you mean if you can have the Page.IsPostBack property set to true without real post back, then the answer is no.

Split a python list into other "sublists" i.e smaller lists

Actually I think using plain slices is the best solution in this case:

for i in range(0, len(data), 100):
    chunk = data[i:i + 100]

If you want to avoid copying the slices, you could use itertools.islice(), but it doesn't seem to be necessary here.

The itertools() documentation also contains the famous "grouper" pattern:

def grouper(n, iterable, fillvalue=None):
    "grouper(3, 'ABCDEFG', 'x') --> ABC DEF Gxx"
    args = [iter(iterable)] * n
    return izip_longest(fillvalue=fillvalue, *args)

You would need to modify it to treat the last chunk correctly, so I think the straight-forward solution using plain slices is preferable.

What is the opposite of :hover (on mouse leave)?

Put your duration time in the non-hover selection:

li a {
  background-color: #111;

li a:hover {

How can I create an MSI setup?

You can purchase InstallShield, the market leader for creating installation packages. It offers many features beyond what you get with freeware solutions.

Warning: InstallShield is insanely expensive!

How do I insert values into a Map<K, V>?

The syntax is

data.put("John","Taxi driver");

How to send data in request body with a GET when using jQuery $.ajax()

Just in case somebody ist still coming along this question:

There is a body query object in any request. You do not need to parse it yourself.

E.g. if you want to send an accessToken from a client with GET, you could do it like this:

const request = require('superagent');_x000D_
request.get(`http://localhost:3000/download?accessToken=${accessToken}`).end((err, res) => {_x000D_
  if (err) throw new Error(err);_x000D_

The server request object then looks like {request: { ... query: { accessToken: abcfed } ... } }

Don't reload application when orientation changes

Just add this to your AndroidManifest.xml

<activity android:screenOrientation="landscape">

I mean, there is an activity tag, add this as another parameter. In case if you need portrait orientation, change landscape to portrait. Hope this helps.

macro - open all files in a folder

Try the below code:

Sub opendfiles()

Dim myfile As Variant
Dim counter As Integer
Dim path As String

myfolder = "D:\temp\"
ChDir myfolder
myfile = Application.GetOpenFilename(, , , , True)
counter = 1
If IsNumeric(myfile) = True Then
    MsgBox "No files selected"
End If
While counter <= UBound(myfile)
    path = myfile(counter)
    Workbooks.Open path
    counter = counter + 1

End Sub

How do I set a path in Visual Studio?

Set the PATH variable, like you're doing. If you're running the program from the IDE, you can modify environment variables by adjusting the Debugging options in the project properties.

If the DLLs are named such that you don't need different paths for the different configuration types, you can add the path to the system PATH variable or to Visual Studio's global one in Tools | Options.

Java: how to initialize String[]?

String[] arr = {"foo", "bar"};

If you pass a string array to a method, do:


or do:

myFunc(new String[] {"foo", "bar"});

How to exit an if clause

Effectively what you're describing are goto statements, which are generally panned pretty heavily. Your second example is far easier to understand.

However, cleaner still would be:

if some_condition:
   if condition_a:


def your_function2():
   if condition_b:
       # do something
       # and then exit the outer if block
       # more code here

Assigning default value while creating migration file

I tried t.boolean :active, :default => 1 in migration file for creating entire table. After ran that migration when i checked in db it made as null. Even though i told default as "1". After that slightly i changed migration file like this then it worked for me for setting default value on create table migration file.

t.boolean :active, :null => false,:default =>1. Worked for me.

My Rails framework version is 4.0.0

How to install multiple python packages at once using pip

You can simply place multiple name together separated by a white space like

C:\Users\Dell>pip install markdown django-filter

#c:\Users\Dell is path in my pc this can be anything on yours

this installed markdown and django-filter on my device. enter image description here

How to convert Observable<any> to array[]

You will need to subscribe to your observables:

    .subscribe(countries => {
        this.myGridOptions.rowData = countries as CountryData[]

And, in your html, wherever needed, you can pass the async pipe to it.

How to use sha256 in php5.3.0

Could this be a typo? (two Ps in ppasscode, intended?)


I would make sure and do:


and make sure the data is accurate there, and then echo out what it should look like:

echo hash('sha256', $_POST['ppasscode']);

Compare this output to what you have in the database (manually). By doing this you're exploring your possible points of failure:

  1. Getting password from form
  2. hashing the password
  3. stored password
  4. comparison of the two.

How to retrieve Request Payload

Also you can setup extJs writer with encode: true and it will send data regularly (and, hence, you will be able to retrieve data via $_POST and $_GET).

... the values will be sent as part of the request parameters as opposed to a raw post (via docs for encode config of


Also docs say that:

The encode option should only be set to true when a root is defined

So, probably, writer's root config is required.

Exporting functions from a DLL with dllexport

If you want plain C exports, use a C project not C++. C++ DLLs rely on name-mangling for all the C++isms (namespaces etc...). You can compile your code as C by going into your project settings under C/C++->Advanced, there is an option "Compile As" which corresponds to the compiler switches /TP and /TC.

If you still want to use C++ to write the internals of your lib but export some functions unmangled for use outside C++, see the second section below.

Exporting/Importing DLL Libs in VC++

What you really want to do is define a conditional macro in a header that will be included in all of the source files in your DLL project:

#    define LIBRARY_API __declspec(dllexport)
#    define LIBRARY_API __declspec(dllimport)

Then on a function that you want to be exported you use LIBRARY_API:

LIBRARY_API int GetCoolInteger();

In your library build project create a define LIBRARY_EXPORTS this will cause your functions to be exported for your DLL build.

Since LIBRARY_EXPORTS will not be defined in a project consuming the DLL, when that project includes the header file of your library all of the functions will be imported instead.

If your library is to be cross-platform you can define LIBRARY_API as nothing when not on Windows:

#ifdef _WIN32
#        define LIBRARY_API __declspec(dllexport)
#    else
#        define LIBRARY_API __declspec(dllimport)
#    endif
#    define LIBRARY_API

When using dllexport/dllimport you do not need to use DEF files, if you use DEF files you do not need to use dllexport/dllimport. The two methods accomplish the same task different ways, I believe that dllexport/dllimport is the recommended method out of the two.

Exporting unmangled functions from a C++ DLL for LoadLibrary/PInvoke

If you need this to use LoadLibrary and GetProcAddress, or maybe importing from another language (i.e PInvoke from .NET, or FFI in Python/R etc) you can use extern "C" inline with your dllexport to tell the C++ compiler not to mangle the names. And since we are using GetProcAddress instead of dllimport we don't need to do the ifdef dance from above, just a simple dllexport:

The Code:

#define EXTERN_DLL_EXPORT extern "C" __declspec(dllexport)

EXTERN_DLL_EXPORT int getEngineVersion() {
  return 1;

EXTERN_DLL_EXPORT void registerPlugin(Kernel &K) {
    auto_ptr<GraphicsServer::GraphicsDriver>(new OpenGLGraphicsDriver())

And here's what the exports look like with Dumpbin /exports:

  Dump of file opengl_plugin.dll

  File Type: DLL

  Section contains the following exports for opengl_plugin.dll

    00000000 characteristics
    49866068 time date stamp Sun Feb 01 19:54:32 2009
        0.00 version
           1 ordinal base
           2 number of functions
           2 number of names

    ordinal hint RVA      name

          1    0 0001110E getEngineVersion = @ILT+265(_getEngineVersion)
          2    1 00011028 registerPlugin = @ILT+35(_registerPlugin)

So this code works fine:

m_hDLL = ::LoadLibrary(T"opengl_plugin.dll");

m_pfnGetEngineVersion = reinterpret_cast<fnGetEngineVersion *>(
  ::GetProcAddress(m_hDLL, "getEngineVersion")
m_pfnRegisterPlugin = reinterpret_cast<fnRegisterPlugin *>(
  ::GetProcAddress(m_hDLL, "registerPlugin")

Unmarshaling nested JSON objects

Like what Volker mentioned, nested structs is the way to go. But if you really do not want nested structs, you can override the UnmarshalJSON func.

type A struct {
    FooBar string // takes
    FooBaz string // takes foo.baz
    More   string 

func (a *A) UnmarshalJSON(b []byte) error {

    var f interface{}
    json.Unmarshal(b, &f)

    m := f.(map[string]interface{})

    foomap := m["foo"]
    v := foomap.(map[string]interface{})

    a.FooBar = v["bar"].(string)
    a.FooBaz = v["baz"].(string)
    a.More = m["more"].(string)

    return nil

Please ignore the fact that I'm not returning a proper error. I left that out for simplicity.

UPDATE: Correctly retrieving "more" value.

Force IE10 to run in IE10 Compatibility View?

I had the same problem. The problem is a bug in MSIE 10, so telling people to fix their issues isn't helpful. Neither is telling visitors to your site to add your site to compatibility view, bleh. In my case, the problem was that the following code displayed no text:

document.write ('<P>'); 
document.write ('Blah, blah, blah... ');
document.write ('</P>');

After much trial and error, I determined that removing the <P> and </P> tags caused the text to appear properly on the page (thus, the problem IS with document mode rather than browser mode, at least in my case). Removing the <P> tags when userAgent is MSIE is not a "fix" I want to put into my pages.

The solution, as others have said, is:

<!DOCTYPE HTML whatever doctype you're using....> 
  <meta http-equiv="X-UA-Compatible" content="IE=EmulateIE8">

Yes, the meta tag has to be the FIRST tag after HEAD.

The order of keys in dictionaries

Just sort the list when you want to use it.

l = sorted(d.keys())

Difference of two date time in sql server

So this isn't my answer but I just found this while searching around online for a question like this as well. This guy set up a procedure to calculate hours, minutes and seconds. The link and the code:

--Creating Function
If OBJECT_ID('UFN_HourMinuteSecond') Is Not Null
Drop Function dbo.UFN_HourMinuteSecond
'Create Function dbo.UFN_HourMinuteSecond
@StartDateTime DateTime,
@EndDateTime DateTime
) Returns Varchar(10) 

Declare @Seconds Int,
@Minute Int,
@Hour Int,
@Elapsed Varchar(10)

Select @Seconds = ABS(DateDiff(SECOND ,@StartDateTime,@EndDateTime))

If @Seconds >= 60 
select @Minute = @Seconds/60
select @Seconds = @Seconds%60

If @Minute >= 60
select @hour = @Minute/60
select @Minute = @Minute%60

Goto Final 

Select @Hour = Isnull(@Hour,0), @Minute = IsNull(@Minute,0), @Seconds =               IsNull(@Seconds,0)
select @Elapsed = Cast(@Hour as Varchar) + '':'' + Cast(@Minute as Varchar) + '':'' +     Cast(@Seconds as Varchar)

Return (@Elapsed)

Changing width property of a :before css selector using JQuery

As Boltclock states in his answer to Selecting and manipulating CSS pseudo-elements such as ::before and ::after using jQuery

Although they are rendered by browsers through CSS as if they were like other real DOM elements, pseudo-elements themselves are not part of the DOM, and thus you can't select and manipulate them with jQuery.

Might just be best to set the style with jQuery instead of using the pseudo CSS selector.

Merging two arrays in .NET

Everyone has already had their say but I think this more readable than the "use as Extension method" approach:

var arr1 = new[] { 1, 2, 3, 4, 5 };
var arr2 = new[] { 6, 7, 8, 9, 0 };
var arr = Queryable.Concat(arr1, arr2).ToArray();

However it can only be used when bringing together 2 arrays.

How do I load an org.w3c.dom.Document from XML in a string?

This works for me in Java 1.5 - I stripped out specific exceptions for readability.

import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.DocumentBuilder;
import org.w3c.dom.Document;

public Document loadXMLFromString(String xml) throws Exception
    DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();

    DocumentBuilder builder = factory.newDocumentBuilder();

    return builder.parse(new ByteArrayInputStream(xml.getBytes()));

Check, using jQuery, if an element is 'display:none' or block on click

another shortcut i personally prefer more than .is() or .length:

   // is visible
}else {
   // is hidden

How to redirect to action from JavaScript method?

I struggled with this a little because I wanted to use Knockout to bind the button to the click event. Here's my button and the relevant function from inside my view model.

<a class="btn btn-secondary showBusy" data-bind="click: back">Back to Dashboard</a>

var vm = function () {
    self.back = function() {
        window.location.href = '@Url.Action("LicenseDashboard", "Application")';

How do I get the AM/PM value from a DateTime?

I know this might seem to be extremely late.. however it may help someone out there

I wanted to get the AM PM part of the date, so I used what Andy advised:


I used that part to construct a Path to save my files.. I built my assumptions that I will get either AM or PM and nothing else !!

however when I used a PC that its culture is not English ..( in my case ARABIC) .. my application failed becase the format "tt" returned something new not AM nor PM (? or ?)..

So the fix to this was to ignore the culture by adding the second argument as follow:

dateTime.ToString("tt", CultureInfo.InvariantCulture);

.. of course u have to add : using System.Globalization; on top of ur file I hope that will help someone :)

SELECT using 'CASE' in SQL

This is just the syntax of the case statement, it looks like this.


As a reminder remember; no assignment is performed the value becomes the column contents. (If you wanted to assign that to a variable you would put it before the CASE statement).

How find out which process is using a file in Linux?

$ lsof | tree MyFold

As shown in the image attached:

enter image description here

Placing an image to the top right corner - CSS

Position the div relatively, and position the ribbon absolutely inside it. Something like:

#content {

.ribbon {

how to add a day to a date using jquery datepicker

The datepicker('setDate') sets the date in the datepicket not in the input.

You should add the date and set it in the input.

var date2 = $('.pickupDate').datepicker('getDate');
var nextDayDate = new Date();
nextDayDate.setDate(date2.getDate() + 1);

Convert canvas to PDF

So for today, jspdf-1.5.3. To answer the question of having the pdf file page exactly same as the canvas. After many tries of different combinations, I figured you gotta do something like this. We first need to set the height and width for the output pdf file with correct orientation, otherwise the sides might be cut off. Then we get the dimensions from the 'pdf' file itself, if you tried to use the canvas's dimensions, the sides might be cut off again. I am not sure why that happens, my best guess is the jsPDF convert the dimensions in other units in the library.

  // Download button
  $("#download-image").on('click', function () {
    let width = __CANVAS.width; 
    let height = __CANVAS.height;

    //set the orientation
    if(width > height){
      pdf = new jsPDF('l', 'px', [width, height]);
      pdf = new jsPDF('p', 'px', [height, width]);
    //then we get the dimensions from the 'pdf' file itself
    width = pdf.internal.pageSize.getWidth();
    height = pdf.internal.pageSize.getHeight();
    pdf.addImage(__CANVAS, 'PNG', 0, 0,width,height);"download.pdf");

Learnt about switching orientations from here:

React-router: How to manually invoke Link?

If you'd like to extend the Link component to utilise some of the logic in it's onClick() handler, here's how:

import React from 'react';
import { Link } from "react-router-dom";

// Extend react-router-dom Link to include a function for validation.
class LinkExtra extends Link {
  render() {
    const linkMarkup = super.render();
    const { validation,} = linkMarkup.props; // Filter out props for <a>.
    const onclick = event => {
      if (!this.props.validation || this.props.validation()) {
      } else {
        console.log("Failed validation");

      <a {} onClick={onclick} />

export default LinkExtra;


<LinkExtra to="/mypage" validation={() => false}>Next</LinkExtra>

How to manually force a commit in a @Transactional method?

I had a similar use case during testing hibernate event listeners which are only called on commit.

The solution was to wrap the code to be persistent into another method annotated with REQUIRES_NEW. (In another class) This way a new transaction is spawned and a flush/commit is issued once the method returns.


Keep in mind that this might influence all the other tests! So write them accordingly or you need to ensure that you can clean up after the test ran.

Regular expression for floating point numbers

I want to match what most languages consider valid numbers (integer and floats):

  • '5' / '-5'

  • '1.0' / '1.' / '.1' / '-1.' / '-.1'

  • '0.45326e+04', '666999e-05', '0.2e-3', '-33.e-1'


  • preceding sign of number ('-' or '+') is optional

  • '-1.' and '-.1' are valid but '.' and '-.' are invalid

  • '.1e3' is valid, but '.e3' and 'e3' are invalid

In order to support both '1.' and '.1' we need an OR operator ('|') in order to make sure we exclude '.' from matching.

[+-]? +/- sing is optional since ? means 0 or 1 matches

( since we have 2 sub expressions we need to put them in parenthesis

\d+([.]\d*)?(e[+-]?\d+)? This is for numbers starting with a digit

| separates sub expressions

[.]\d+(e[+-]?\d+)? this is for numbers starting with '.'

) end of expressions

  • For numbers starting with '.'

[.] first character is dot (inside brackets or else it is a wildcard character)

\d+ one or more digits

(e[+-]?\d+)? this is an optional (0 or 1 matches due to ending '?') scientific notation

  • For numbers starting with a digit

\d+ one or more digits

([.]\d*)? optionally we can have a dot character an zero or more digits after it

(e[+-]?\d+)? this is an optional scientific notation

  • Scientific notation

e literal that specifies exponent

[+-]? optional exponent sign

\d+ one or more digits

All of those combined:


To accept E as well:


(Test cases)

Nested or Inner Class in PHP

Real nested classes with public/protected/private accessibility were proposed in 2013 for PHP 5.6 as an RFC but did not make it (No voting yet, no update since 2013 - as of 2021/02/03):

class foo {
    public class bar {

At least, anonymous classes made it into PHP 7

From this RFC page:

Future Scope

The changes made by this patch mean named nested classes are easier to implement (by a tiny bit).

So, we might get nested classes in some future version, but it's not decided yet.

Crop image in android

I found a really cool library, try this out. this is really smooth and easy to use.

iPhone get SSID without private library

UPDATE FOR iOS 10 and up

CNCopySupportedInterfaces is no longer deprecated in iOS 10. (API Reference)

You need to import SystemConfiguration/CaptiveNetwork.h and add SystemConfiguration.framework to your target's Linked Libraries (under build phases).

Here is a code snippet in swift (RikiRiocma's Answer):

import Foundation
import SystemConfiguration.CaptiveNetwork

public class SSID {
    class func fetchSSIDInfo() -> String {
        var currentSSID = ""
        if let interfaces = CNCopySupportedInterfaces() {
            for i in 0..<CFArrayGetCount(interfaces) {
                let interfaceName: UnsafePointer<Void> = CFArrayGetValueAtIndex(interfaces, i)
                let rec = unsafeBitCast(interfaceName, AnyObject.self)
                let unsafeInterfaceData = CNCopyCurrentNetworkInfo("\(rec)")
                if unsafeInterfaceData != nil {
                    let interfaceData = unsafeInterfaceData! as Dictionary!
                    currentSSID = interfaceData["SSID"] as! String
        return currentSSID

(Important: CNCopySupportedInterfaces returns nil on simulator.)

For Objective-c, see Esad's answer here and below

+ (NSString *)GetCurrentWifiHotSpotName {    
    NSString *wifiName = nil;
    NSArray *ifs = (__bridge_transfer id)CNCopySupportedInterfaces();
    for (NSString *ifnam in ifs) {
        NSDictionary *info = (__bridge_transfer id)CNCopyCurrentNetworkInfo((__bridge CFStringRef)ifnam);
        if (info[@"SSID"]) {
            wifiName = info[@"SSID"];
    return wifiName;


As of iOS 9 Captive Network is deprecated*. (source)

*No longer deprecated in iOS 10, see above.

It's recommended you use NEHotspotHelper (source)

You will need to email apple at [email protected] and request entitlements. (source)

Sample Code (Not my code. See Pablo A's answer):

for(NEHotspotNetwork *hotspotNetwork in [NEHotspotHelper supportedNetworkInterfaces]) {
    NSString *ssid = hotspotNetwork.SSID;
    NSString *bssid = hotspotNetwork.BSSID;
    BOOL secure =;
    BOOL autoJoined = hotspotNetwork.autoJoined;
    double signalStrength = hotspotNetwork.signalStrength;

Side note: Yup, they deprecated CNCopySupportedInterfaces in iOS 9 and reversed their position in iOS 10. I spoke with an Apple networking engineer and the reversal came after so many people filed Radars and spoke out about the issue on the Apple Developer forums.

How to check if a windows form is already open, and close it if it is?

Form only once

If your goal is to diallow multiple instaces of a form, consider following ...

public class MyForm : Form
    private static MyForm alreadyOpened = null;

    public MyForm()
        // If the form already exists, and has not been closed
        if (alreadyOpened != null && !alreadyOpened.IsDisposed)
            alreadyOpened.Focus();            // Bring the old one to top
            Shown += (s, e) => this.Close();  // and destroy the new one.

        // Otherwise store this one as reference
        alreadyOpened = this;  

        // Initialization

Warning: Null value is eliminated by an aggregate or other SET operation in Aqua Data Studio

If any Null value exists inside aggregate function you will face this issue. Instead of below code

 SELECT Count(closed)
  FROM   ticket
  WHERE  assigned_to = c.user_id
  AND closed IS NULL

use like

SELECT Count(ISNULL(closed, 0))
  FROM   ticket
  WHERE  assigned_to = c.user_id
  AND closed IS NULL

ggplot2, change title size

+ theme(plot.title = element_text(size=22))

Here is the full set of things you can change in element_text:

element_text(family = NULL, face = NULL, colour = NULL, size = NULL,
  hjust = NULL, vjust = NULL, angle = NULL, lineheight = NULL,
  color = NULL)

Multiple select in Visual Studio?

MixEdit extension for Visual Studio allows you to do multiediting in the way you are describing. It supports multiple carets and multiple selections.

The character encoding of the plain text document was not declared - mootool script

I got this error using Spring Boot (in Mozilla),

because I was just testing some basic controller -> service -> repository communication by directly returning some entities from the database to the browser (as JSON).

I forgot to put data in the database, so my method wasn't returning anything... and I got this error.

Now that I put some data in my db, it works fine (the error is removed). :D

How to use continue in jQuery each() loop?

We can break both a $(selector).each() loop and a $.each() loop at a particular iteration by making the callback function return false. Returning non-false is the same as a continue statement in a for loop; it will skip immediately to the next iteration.

return false; // this is equivalent of 'break' for jQuery loop

return;       // this is equivalent of 'continue' for jQuery loop

Note that $(selector).each() and $.each() are different functions.


Where can I download an offline installer of Cygwin?

may this post can solve your problem

see Full Installation Answer on that: What is the current full install size of Cygwin?

"starting Tomcat server 7 at localhost has encountered a prob"

Hey i got the solution recently... Just copy the "ROOT" folder FROM C:\Program Files\ Apache Software Foundation\ Tomcat 7.0\ webapps \ TO your_Workspace\ .metadata\ .plugins\ org.eclipse.wst.server.core\ tmp0 \wtpwebapps\ and over write it when asked..

This is needed because eclipse forgets to copy that root folder to its workspace.. Just right click on Apache tomcat 7.0 in servers tab and observe that in location will be workspace metadata by default example:"location:[workspace metadata]". Therefore it will find the root folder which has the welcome page in it and the 404 page not found error will be displayed. Thankyou ..

Removing NA in dplyr pipe

I don't think desc takes an na.rm argument... I'm actually surprised it doesn't throw an error when you give it one. If you just want to remove NAs, use na.omit (base) or tidyr::drop_na:

outcome.df %>%
  na.omit() %>%
  group_by(Hospital, State) %>%
  arrange(desc(HeartAttackDeath)) %>%

outcome.df %>%
  drop_na() %>%
  group_by(Hospital, State) %>%
  arrange(desc(HeartAttackDeath)) %>%

If you only want to remove NAs from the HeartAttackDeath column, filter with, or use tidyr::drop_na:

outcome.df %>%
  filter(! %>%
  group_by(Hospital, State) %>%
  arrange(desc(HeartAttackDeath)) %>%

outcome.df %>%
  drop_na(HeartAttackDeath) %>%
  group_by(Hospital, State) %>%
  arrange(desc(HeartAttackDeath)) %>%

As pointed out at the dupe, complete.cases can also be used, but it's a bit trickier to put in a chain because it takes a data frame as an argument but returns an index vector. So you could use it like this:

outcome.df %>%
  filter(complete.cases(.)) %>%
  group_by(Hospital, State) %>%
  arrange(desc(HeartAttackDeath)) %>%

Converting char* to float or double

printf("price: %d, %f",temp,ftemp); 

This is your problem. Since the arguments are type double and float, you should be using %f for both (since printf is a variadic function, ftemp will be promoted to double).

%d expects the corresponding argument to be type int, not double.

Variadic functions like printf don't really know the types of the arguments in the variable argument list; you have to tell it with the conversion specifier. Since you told printf that the first argument is supposed to be an int, printf will take the next sizeof (int) bytes from the argument list and interpret it as an integer value; hence the first garbage number.

Now, it's almost guaranteed that sizeof (int) < sizeof (double), so when printf takes the next sizeof (double) bytes from the argument list, it's probably starting with the middle byte of temp, rather than the first byte of ftemp; hence the second garbage number.

Use %f for both.

Visual Studio 2015 Update 3 Offline Installer (ISO)

The ISO file that suggested in the accepted answer is still not complete. The very complete offline installer is about 24GB! There is only one way to get it. follow these steps:

  1. Download Web Installer from Microsoft Web Site
  2. Execute the Installer. NOTE: the installer is still a simple downloader for the real web-installer.
  3. After running the real web installer, Run Windows Task manager and find the real web installer path that is stored in your temp folder
  4. copy the real installer somewhere else. like C:\VS Community\
  5. Open Command Prompt and execute the installer that you copied to C:\VS Community\ with this argument: /Layout .
  6. Now installer will download the FULL offline installer to your selected folder!

Good Luck

Faking an RS232 Serial Port

Another alternative, even though the OP did not ask for it:

There exist usb-to-serial adapters. Depending on the type of adapter, you may also need a nullmodem cable, too.

They are extremely easy to use under linux, work under windows, too, if you have got working drivers installed.

That way you can work directly with the sensors, and you do not have to try and emulate data. That way you are maybe even save from building an anemic system. (Due to your emulated data inputs not covering all cases, leading you to a brittle system.)

Its often better to work with the real stuff.

How to get address location from latitude and longitude in Google Map.?

You have to make one ajax call to get the required result, in this case you can use Google API to get the same,-73.961452&sensor=true/false

Build this kind of url and replace the lat long with the one you want to. do the call and response will be in JSON, parse the JSON and you will get the complete address up to street level

Javascript to stop HTML5 video playback on modal window close

None of these worked for me using 4.1 video.js CDN. This code kills the video playing in a modal when the (.closemodal) is clicked. I had 3 videos. Someone else can refactor.

var myPlayer = videojs("my_video_1");
var myPlayer2 = videojs("my_video_2");
var myPlayer3 = videojs("my_video_3");

as per their Api docs.

How do I replace whitespaces with underscore?

You don't need regular expressions. Python has a built-in string method that does what you need:

mystring.replace(" ", "_")

How do you check what version of SQL Server for a database using TSQL?


SELECT @@MICROSOFTVERSION / 0x01000000 AS MajorVersionNumber

For more information see: Querying for version/edition info

Insert all data of a datagridview to database at once

Please see if below can help you

Class Post_Sales

Public Shared Sub Post_sales()

    Dim ITM_ID As Integer

    Dim SLS_QTY As Integer

    Dim SLS_PRC As Double

    Dim SLS_AMT As Double

    Dim DSPL_RCT As String

    Dim TAX_CODE As Integer

    'Format the current  date and send it to a textbox
    Form1.TextBox6.Text = System.DateTime.Now.ToString((" yyyy-MM-dd"))

    'Open Connection

    Dim con As New SqlConnection("Initial Catalog=Your Database here;Data source=.;Network Library=DBMSSOCN;User ID=sa;Password=")


    'Insert Records into the database

    For Each rw As DataGridViewRow In Form1.DataGridView1.Rows

        ITM_ID = rw.Cells("Column1").Value
        DSPL_RCT = rw.Cells("Column2").Value
        SLS_QTY = rw.Cells("Column3").Value
        SLS_PRC = rw.Cells("Column4").Value
        SLS_AMT = rw.Cells("Column5").Value
        TAX_CODE = rw.Cells("Column6").Value

        Dim cmd As New SqlCommand("INSERT INTO DAY_PLUSALES (DT,ITM_ID,DSPL_RCT,SLS_QTY,SLS_PRC,SLS_AMT,TAX_CODE) values ('" & Form1.TextBox6.Text & "','" & ITM_ID & "','" & DSPL_RCT & "','" & SLS_QTY & "','" & SLS_PRC & "','" & SLS_AMT & "','" & TAX_CODE & "')", con)




    MessageBox.Show("Records Added to the SQL Database successfully!", "Records Updated ")

End Sub

End Class

javascript - match string against the array of regular expressions

let expressions = [ '/something/', '/something_else/', '/and_something_else/'];

let str = 'else';

here will be the check for following expressions:

if( expressions.find(expression => expression.includes(str) ) ) {


using Array .find() method to traverse array and .include to check substring

What is the difference between Tomcat, JBoss and Glassfish?

It seems a bit discouraging to use Tomcat when you read these answers. However what most fail to mention is that you can get to identical or almost identical use cases with tomcat but that requires you to add the libraries needed (through Maven or whatever include system you use).

I have been running tomcat with JPA, EJBs with very small configuration efforts.

What is a Sticky Broadcast?

A normal broadcast Intent is not available anymore after is was send and processed by the system. If you use the sendStickyBroadcast(Intent) method, the Intent is sticky, meaning the Intent you are sending stays around after the broadcast is complete.

you refer to my blog:enter link description here

How to start anonymous thread class

Just call start()

new Thread()
    public void run() {

How to convert image file data in a byte array to a Bitmap?

Just try this:

Bitmap bitmap = BitmapFactory.decodeFile("/path/images/image.jpg");
ByteArrayOutputStream blob = new ByteArrayOutputStream();
bitmap.compress(CompressFormat.PNG, 0 /* Ignored for PNGs */, blob);
byte[] bitmapdata = blob.toByteArray();

If bitmapdata is the byte array then getting Bitmap is done like this:

Bitmap bitmap = BitmapFactory.decodeByteArray(bitmapdata, 0, bitmapdata.length);

Returns the decoded Bitmap, or null if the image could not be decoded.

Accessing Websites through a Different Port?

If website server is listening to a different port, then yes, simply use http://address:port/

If server is not listening to a different port, then obviously you cannot.

How to specify function types for void (not Void) methods in Java8?

You are trying to use the wrong interface type. The type Function is not appropriate in this case because it receives a parameter and has a return value. Instead you should use Consumer (formerly known as Block)

The Function type is declared as

interface Function<T,R> {
  R apply(T t);

However, the Consumer type is compatible with that you are looking for:

interface Consumer<T> {
   void accept(T t);

As such, Consumer is compatible with methods that receive a T and return nothing (void). And this is what you want.

For instance, if I wanted to display all element in a list I could simply create a consumer for that with a lambda expression:

List<String> allJedi = asList("Luke","Obiwan","Quigon");
allJedi.forEach( jedi -> System.out.println(jedi) );

You can see above that in this case, the lambda expression receives a parameter and has no return value.

Now, if I wanted to use a method reference instead of a lambda expression to create a consume of this type, then I need a method that receives a String and returns void, right?.

I could use different types of method references, but in this case let's take advantage of an object method reference by using the println method in the System.out object, like this:

Consumer<String> block = System.out::println

Or I could simply do


The println method is appropriate because it receives a value and has a return type void, just like the accept method in Consumer.

So, in your code, you need to change your method signature to somewhat like:

public static void myForEach(List<Integer> list, Consumer<Integer> myBlock) {

And then you should be able to create a consumer, using a static method reference, in your case by doing:

myForEach(theList, Test::displayInt);

Ultimately, you could even get rid of your myForEach method altogether and simply do:


About Functions as First Class Citizens

All been said, the truth is that Java 8 will not have functions as first-class citizens since a structural function type will not be added to the language. Java will simply offer an alternative way to create implementations of functional interfaces out of lambda expressions and method references. Ultimately lambda expressions and method references will be bound to object references, therefore all we have is objects as first-class citizens. The important thing is the functionality is there since we can pass objects as parameters, bound them to variable references and return them as values from other methods, then they pretty much serve a similar purpose.

Inserting data into a MySQL table using VB.NET

  • First, You missed this one: sqlCommand.CommandType = CommandType.Text
  • Second, Your MySQL Parameter Declaration is wrong. It should be @ and not ?

try this:

Public Function InsertCar() As Boolean

    Dim iReturn as boolean
    Using SQLConnection As New MySqlConnection(connectionString)
        Using sqlCommand As New MySqlCommand()
            With sqlCommand
                .CommandText = "INSERT INTO members_car (`car_id`, `member_id`, `model`, `color`, `chassis_id`, `plate_number`, `code`) values (@xid,@m_id,@imodel,@icolor,@ch_id,@pt_num,@icode)"
                .Connection = SQLConnection
                .CommandType = CommandType.Text // You missed this line
                .Parameters.AddWithValue("@xid", TextBox20.Text)
                .Parameters.AddWithValue("@m_id", TextBox20.Text)
                .Parameters.AddWithValue("@imodel", TextBox23.Text)
                .Parameters.AddWithValue("@icolor", TextBox24.Text)
                .Parameters.AddWithValue("@ch_id", TextBox22.Text)
                .Parameters.AddWithValue("@pt_num", TextBox21.Text)
                .Parameters.AddWithValue("@icode", ComboBox1.SelectedItem)
            End With
                iReturn = TRUE
            Catch ex As MySqlException
                MsgBox ex.Message.ToString
                iReturn = False
            End Try
        End Using
    End Using

   Return iReturn

End Function

Doing HTTP requests FROM Laravel to an external API

As of Laravel v7.X, the framework now comes with a minimal API wrapped around the Guzzle HTTP client. It provides an easy way to make get, post, put, patch, and delete requests using the HTTP Client:

use Illuminate\Support\Facades\Http;

$response = Http::get('');
$response = Http::post('');
$response = Http::put('');
$response = Http::patch('');
$response = Http::delete('');

You can manage responses using the set of methods provided by the Illuminate\Http\Client\Response instance returned.

$response->body() : string;
$response->json() : array;
$response->status() : int;
$response->ok() : bool;
$response->successful() : bool;
$response->serverError() : bool;
$response->clientError() : bool;
$response->header($header) : string;
$response->headers() : array;

Please note that you will, of course, need to install Guzzle like so:

composer require guzzlehttp/guzzle

There are a lot more helpful features built-in and you can find out more about these set of the feature here:

This is definitely now the easiest way to make external API calls within Laravel.

Regular vs Context Free Grammars

I think what you want to think about are the various pumping lemmata. A regular language can be recognized by a finite automaton. A context-free language requires a stack, and a context sensitive language requires two stacks (which is equivalent to saying it requires a full Turing machine.)

So, if we think about the pumping lemma for regular languages, what it says, essentially, is that any regular language can be broken down into three pieces, x, y, and z, where all instances of the language are in xy*z (where * is Kleene repetition, ie, 0 or more copies of y.) You basically have one "nonterminal" that can be expanded.

Now, what about context-free languages? There's an analogous pumping lemma for context-free languages that breaks the strings in the language into five parts, uvxyz, and where all instances of the language are in uvixyiz, for i ≥ 0. Now, you have two "nonterminals" that can be replicated, or pumped, as long as you have the same number.

How can I simulate a click to an anchor tag?

None of the above solutions address the generic intention of the original request. What if we don't know the id of the anchor? What if it doesn't have an id? What if it doesn't even have an href parameter (e.g. prev/next icon in a carousel)? What if we want to apply the action to multiple anchors with different models in an agnostic fashion? Here's an example that does something instead of a click, then later simulates the click (for any anchor or other tag):

var clicker = null;
    clicker=$(this); // capture the clicked dom object
    /* ... do something ... */
    e.preventDefault(); // prevent original click action
clicker[0].click(); // this repeats the original click. [0] is necessary.

How do I update a Tomcat webapp without restarting the entire service?

There are multiple easy ways.

  1. Just touch web.xml of any webapp.

    touch /usr/share/tomcat/webapps/<WEBAPP-NAME>/WEB-INF/web.xml

You can also update a particular jar file in WEB-INF/lib and then touch web.xml, rather than building whole war file and deploying it again.

  1. Delete webapps/YOUR_WEB_APP directory, Tomcat will start deploying war within 5 seconds (assuming your war file still exists in webapps folder).

  2. Generally overwriting war file with new version gets redeployed by tomcat automatically. If not, you can touch web.xml as explained above.

  3. Copy over an already exploded "directory" to your webapps folder

Cannot construct instance of - Jackson

For me there was no default constructor defined for the POJOs I was trying to use. creating default constructor fixed it.

public class TeamCode {

    private String value;

    public String getValue() {
        return value;

    **public TeamCode() {

    public TeamCode(String value) {
        this.value = value;

    public String toString() {
        return "TeamCode{" +
                "value='" + value + '\'' +

    public void setValue(String value) {
        this.value = value;


Creating a very simple 1 username/password login in php

Here is a simple php script for login and a page that can only be accessed by logged in users.


    echo isset($_SESSION['login']);
    if(isset($_SESSION['login'])) {
      header('LOCATION:index.php'); die();
<!DOCTYPE html>
     <meta http-equiv='content-type' content='text/html;charset=utf-8' />
     <meta charset="utf-8">
     <meta name="viewport" content="width=device-width, initial-scale=1">
     <link rel="stylesheet" href="">
  <div class="container">
    <h3 class="text-center">Login</h3>
        $username = $_POST['username']; $password = $_POST['password'];
        if($username === 'admin' && $password === 'password'){
          $_SESSION['login'] = true; header('LOCATION:admin.php'); die();
        } {
          echo "<div class='alert alert-danger'>Username and Password do not match.</div>";

    <form action="" method="post">
      <div class="form-group">
        <label for="username">Username:</label>
        <input type="text" class="form-control" id="username" name="username" required>
      <div class="form-group">
        <label for="pwd">Password:</label>
        <input type="password" class="form-control" id="pwd" name="password" required>
      <button type="submit" name="submit" class="btn btn-default">Login</button>

admin.php ( only logged in users can access it )

    if(!isset($_SESSION['login'])) {
        header('LOCATION:login.php'); die();
        <title>Admin Page</title>
        This is admin page view able only by logged in users.

Sort arrays of primitive types in descending order

I think the easiest solution is still:

  1. Getting the natural order of the array
  2. Finding the maximum within that sorted array which is then the last item
  3. Using a for-loop with decrement operator

As said by others before: using toList is additional effort, Arrays.sort(array,Collections.reverseOrder()) doesn't work with primitives and using an extra framework seems too complicated when all you need is already inbuild and therefore probably faster as well...

Sample code:

import java.util.Arrays;

public class SimpleDescending {

    public static void main(String[] args) {

        // unsorted array
        int[] integerList = {55, 44, 33, 88, 99};

        // Getting the natural (ascending) order of the array

        // Getting the last item of the now sorted array (which represents the maximum, in other words: highest number)
        int max = integerList.length-1;

        // reversing the order with a simple for-loop
        System.out.println("Array in descending order:");
        for(int i=max; i>=0; i--) {

        // You could make the code even shorter skipping the variable max and use
        // "int i=integerList.length-1" instead of int "i=max" in the parentheses of the for-loop

How to get df linux command output always in GB

You can use the -B option.

Man page of df:

-B, --block-size=SIZE use SIZE-byte blocks

All together,

df -BG

How to get all checked checkboxes

Get all the checked checkbox value in an array - one liner

const data = [...document.querySelectorAll('.inp:checked')].map(e => e.value);_x000D_
<div class="row">_x000D_
    <input class="custom-control-input inp"type="checkbox" id="inlineCheckbox1" Checked value="option1"> _x000D_
    <label class="custom-control-label" for="inlineCheckbox1">Option1</label>_x000D_
    <input class="custom-control-input inp"  type="checkbox" id="inlineCheckbox1" value="option2"> _x000D_
    <label class="custom-control-label" for="inlineCheckbox1">Option2</label>_x000D_
    <input class="custom-control-input inp" Checked  type="checkbox" id="inlineCheckbox1" value="option3"> _x000D_
    <label class="custom-control-label" for="inlineCheckbox1">Option3</label>_x000D_

How can I create a dynamic button click event on a dynamic button?

Button button = new Button();
button.Click += (s,e) => { your code; };
//button.Click += new EventHandler(button_Click);

//protected void button_Click (object sender, EventArgs e) { }

Using CSS for a fade-in effect on page load

You can use the onload="" HTML attribute and use JavaScript to adjust the opacity style of your element.

Leave your CSS as you proposed. Edit your HTML code to:

<body onload="document.getElementById(test).style.opacity='1'">
    <div id="test">
        <p>?This is a test</p>

This also works to fade-in the complete page when finished loading:


<body onload="'1'">


    opacity: 0;
    transition: opacity 2s;
    -webkit-transition: opacity 2s; /* Safari */

Check the W3Schools website: transitions and an article for changing styles with JavaScript.

Get Cell Value from Excel Sheet with Apache Poi

You have to use the FormulaEvaluator, as shown here. This will return a value that is either the value present in the cell or the result of the formula if the cell contains such a formula :

FileInputStream fis = new FileInputStream("/somepath/test.xls");
Workbook wb = new HSSFWorkbook(fis); //or new XSSFWorkbook("/somepath/test.xls")
Sheet sheet = wb.getSheetAt(0);
FormulaEvaluator evaluator = wb.getCreationHelper().createFormulaEvaluator();

// suppose your formula is in B3
CellReference cellReference = new CellReference("B3"); 
Row row = sheet.getRow(cellReference.getRow());
Cell cell = row.getCell(cellReference.getCol()); 

if (cell!=null) {
    switch (evaluator.evaluateFormulaCell(cell)) {
        case Cell.CELL_TYPE_BOOLEAN:
        case Cell.CELL_TYPE_NUMERIC:
        case Cell.CELL_TYPE_STRING:
        case Cell.CELL_TYPE_BLANK:
        case Cell.CELL_TYPE_ERROR:

        // CELL_TYPE_FORMULA will never occur
        case Cell.CELL_TYPE_FORMULA: 

if you need the exact contant (ie the formla if the cell contains a formula), then this is shown here.

Edit : Added a few example to help you.

first you get the cell (just an example)

Row row = sheet.getRow(rowIndex+2);    
Cell cell = row.getCell(1);   

If you just want to set the value into the cell using the formula (without knowing the result) :

 String formula ="ABS((1-E"+(rowIndex + 2)+"/D"+(rowIndex + 2)+")*100)";    

if you want to change the message if there is an error in the cell, you have to change the formula to do so, something like

IF(ISERR(ABS((1-E3/D3)*100));"N/A"; ABS((1-E3/D3)*100))

(this formula check if the evaluation return an error and then display the string "N/A", or the evaluation if this is not an error).

if you want to get the value corresponding to the formula, then you have to use the evaluator.

Hope this help,

Data-frame Object has no Attribute

Quick fix: Change how excel converts imported files. Go to 'File', then 'Options', then 'Advanced'. Scroll down and uncheck 'Use system seperators'. Also change 'Decimal separator' to '.' and 'Thousands separator' to ',' . Then simply 're-save' your file in the CSV (Comma delimited) format. The root cause is usually associated with how the csv file is created. Trust that helps. Point is, why use extra code if not necessary? Cross-platform understanding and integration is key in engineering/development.

get path for my .exe

In a Windows Forms project:

For the full path (filename included): string exePath = Application.ExecutablePath;
For the path only: string appPath = Application.StartupPath;

Mongoose: Find, modify, save

I wanted to add something very important. I use JohnnyHK method a lot but I noticed sometimes the changes didn't persist to the database. When I used .markModified it worked.

User.findOne({username: oldUsername}, function (err, user) {
   user.username = newUser.username;
   user.password = newUser.password;
   user.rights = newUser.rights;

   user.markModified(rights) (err) {
    if(err) {

tell mongoose about the change with doc.markModified('pathToYourDate') before saving.

How to set column widths to a jQuery datatable?

The best solution I found this to work for me guys after trying all the other solutions.... Basically i set the sScrollX to 200% then set the individual column widths to the required % that I wanted. The more columns that you have and the more space that you require then you need to raise the sScrollX %... The null means that I want those columns to retain the datatables auto width they have set in their code. enter image description here

                "sScrollX": "200%", //This is what made my columns increase in size.
                "bScrollCollapse": true,
                "sScrollY": "320px",

                "bAutoWidth": false,
                "aoColumns": [
                    { "sWidth": "10%" }, // 1st column width 
                    { "sWidth": "null" }, // 2nd column width 
                    { "sWidth": "null" }, // 3rd column width
                    { "sWidth": "null" }, // 4th column width 
                    { "sWidth": "40%" }, // 5th column width 
                    { "sWidth": "null" }, // 6th column width
                    { "sWidth": "null" }, // 7th column width 
                    { "sWidth": "10%" }, // 8th column width 
                    { "sWidth": "10%" }, // 9th column width
                    { "sWidth": "40%" }, // 10th column width
                    { "sWidth": "null" } // 11th column width
                "bPaginate": true,              
                "sDom": '<"H"TCfr>t<"F"ip>',
                    "aButtons": [ "copy", "csv", "print", "xls", "pdf" ],
                    "sSwfPath": "copy_cvs_xls_pdf.swf"
                "aaSorting":[[0, "desc"]],


How to dismiss a Twitter Bootstrap popover by clicking outside?

According to highest two answers, I have a little fix:

<span class="btn btn-info btn-minier popover-info" data-rel="popover"
                                              data-placement="bottom" data-html="true" title=""
                                            <i class="ace-icon fa fa-info smaller-100"></i>
            $('[data-rel=popover]').popover({html: true});
            $(document).on("", '[data-rel=popover]', function () {
                $(this).attr('popover-show', '1');
            $(document).on("", '[data-rel=popover]', function () {
                if ($(this).attr('popover-show') === '0') {
                    // My important fix: using bootstrap 3.4.1, if hide popover by .popover('hide') and click to show, popover internal treat it is already shown and dispatch hidden event immediately without popover anything.
                } else {
                    $(this).attr('popover-show', '0');
            $('html').on('click', function (e) {
                if (typeof $('original-title') == 'undefined'
                    && typeof $('original-title') == 'undefined'
                    && !$('')) {

base64 encoded images in email signatures

Recently I had the same problem to include QR image/png in email. The QR image is a byte array which is generated using ZXing. We do not want to save it to a file because saving/reading from a file is too expensive (slow). So both of the answers above do not work for me. Here's what I did to solve this problem:

import javax.mail.util.ByteArrayDataSource;
import org.apache.commons.mail.ImageHtmlEmail;
ImageHtmlEmail email = new ImageHtmlEmail();
byte[] qrImageBytes = createQRCode(); // get your image byte array
ByteArrayDataSource qrImageDataSource = new ByteArrayDataSource(qrImageBytes, "image/png");
String contentId = email.embed(qrImageDataSource, "QR Image");

Let's say the contentId is "111122223333", then your HTML part should have this:

<img src="cid: 111122223333">

There's no need to convert the byte array to Base64 because Commons Mail does the conversion for you automatically. Hope this helps.

I do not want to inherit the child opacity from the parent in CSS

My answer is not about static parent-child layout, its about animations.

I was doing an svg demo today, and i needed svg to be inside div (because svg is created with parent's div width and height, to animate the path around), and this parent div needed to be invisible during svg path animation (and then this div was supposed to animate opacity from 0 to 1, it's the most important part). And because parent div with opacity: 0 was hiding my svg, i came across this hack with visibility option (child with visibility: visible can be seen inside parent with visibility: hidden):

.main.invisible .test {
  visibility: hidden;
.main.opacity-zero .test {
  opacity: 0;
  transition: opacity 0s !important;
.test { // parent div
  transition: opacity 1s;
.test-svg { // child svg
  visibility: visible;

And then, in js, you removing .invisible class with timeout function, adding .opacity-zero class, trigger layout with something like; and removing .opacity-zero class.

var $main = $(".main");
  setTimeout(function() {
  }, 3000);

Better to check this demo

How do I set ANDROID_SDK_HOME environment variable?

Copy your SDK path and assign it to the environment variable ANDROID_SDK_ROOT

Refer pic below:

enter image description here

Read file from resources folder in Spring Boot

After spending a lot of time trying to resolve this issue, finally found a solution that works. The solution makes use of Spring's ResourceUtils. Should work for json files as well.

Thanks for the well written page by Lokesh Gupta : Blog

enter image description here

package utils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.util.ResourceUtils;

import java.util.Properties;

public class Utils {

    private static final Logger LOGGER = LoggerFactory.getLogger(Utils.class.getName());

    public static Properties fetchProperties(){
        Properties properties = new Properties();
        try {
            File file = ResourceUtils.getFile("");
            InputStream in = new FileInputStream(file);
        } catch (IOException e) {
        return properties;

To answer a few concerns on the comments :

Pretty sure I had this running on Amazon EC2 using java -jar target/image-service-slave-1.0-SNAPSHOT.jar

Look at my github repo : to figure out the right way to run this from a JAR.

Select SQL Server database size

There are already a lot of great answers here but it's worth mentioning a simple and quick way to get the SQL Server Database size with SQL Server Management Studio (SSMS) using a standard report.

To run a report you need:

  1. right-click on the database
  2. go to Reports > Standard Reports > Disk Usage.

It prints a nice report:

enter image description here

Where the Total space Reserved is the total size of the database on the disk and it includes the size of all data files and the size of all transaction log files.

Under the hood, SSMS uses dbo.sysfiles view or sys.database_files view (depending on the version of MSSQL) and some kind of this query to get the Total space Reserved value:

SELECT sum((convert(dec (19, 2),  
convert(bigint,SIZE))) * 8192 / 1048576.0) db_size_mb
FROM dbo.sysfiles;

How can I beautify JSON programmatically?

Here's something that might be interesting for developers hacking (minified or obfuscated) JavaScript more frequently.

You can build your own CLI JavaScript beautifier in under 5 mins and have it handy on the command-line. You'll need Mozilla Rhino, JavaScript file of some of the JS beautifiers available online, small hack and a script file to wrap it all up.

I wrote an article explaining the procedure: Command-line JavaScript beautifier implemented in JavaScript.

image processing to improve tesseract OCR accuracy

you can do noise reduction and then apply thresholding, but that you can you can play around with the configuration of the OCR by changing the --psm and --oem values

try: --psm 5 --oem 2

you can also look at the following link for further details here

Making an array of integers in iOS

If the order of your integers is not required, and if there are only unique values

you can also use NSIndexSet or NSMutableIndexSet You will be able to easily add and remove integers, or check if your array contains an integer with

- (void)addIndex:(NSUInteger)index
- (void)removeIndex:(NSUInteger)index
- (BOOL)containsIndexes:(NSIndexSet *)indexSet

Check the documentation for more info.

Sanitizing user input before adding it to the DOM in Javascript

You could use a simple regular expression to assert that the id only contains allowed characters, like so:

    //The id is fine
    //The id is illegal

My example allows only alphanumerical characters, and strings of length 1 to 16, you should change it to match the type of ids that you use.

By the way, at line 6, the value property is missing a pair of quotes, an easy mistake to make when you quote on two levels.

I can't see your actual data flow, depending on context this check may not at all be needed, or it may not be enough. In order to make a proper security review we would need more information.

In general, about built in escape or sanitize functions, don't trust them blindly. You need to know exactly what they do, and you need to establish that that is actually what you need. If it is not what you need, the code your own, most of the time a simple whitelisting regex like the one I gave you works just fine.

file_get_contents behind a proxy?

There's a similar post here: which explains how to do it.

function file_get_contents_proxy($url,$proxy){

    // Create context stream
    $context_array = array('http'=>array('proxy'=>$proxy,'request_fulluri'=>true));
    $context = stream_context_create($context_array);

    // Use context stream with file_get_contents
    $data = file_get_contents($url,false,$context);

    // Return data via proxy
    return $data;


What's the difference between SHA and AES encryption?

SHA doesn't require anything but an input to be applied, while AES requires at least 3 things - what you're encrypting/decrypting, an encryption key, and the initialization vector.

What possibilities can cause "Service Unavailable 503" error?

Your web pages are served by an application pool. If you disable/stop the application pool, and anyone tries to browse the application, you will get a Service Unavailable. It can happen due to multiple reasons...

  1. Your application may have crashed [check the event viewer and see if you can find event logs in your Application/System log]

  2. Your application may be crashing very frequently. If an app pool crashes for 5 times in 5 minutes [check your application pool settings for rapid fail], your application pool is disabled by IIS and you will end up getting this message.

In either case, the issue is that your worker process is failing and you should troubleshoot it from crash perspective.

What is a Crash (technically)... in ASP.NET and what to do if it happens?

A fatal error occurred while creating a TLS client credential. The internal error state is 10013

After making no changes to a production server we began receiving this error. After trying several different things and thinking that perhaps there were DNS issues, restarting IIS fixed the issue (restarting only the site did not fix the issue). It likely won't work for everyone but if we tried that first it would have saved a lot of time.

Allowing Untrusted SSL Certificates with HttpClient

Most answers here suggest to use the typical pattern:

using (var httpClient = new HttpClient())
 // do something

because of the IDisposable interface. Please don't!

Microsoft tells you why:

And here you can find a detailed analysis whats going on behind the scenes: You're using HttpClient wrong and it is destabilizing your software

Regarding your SSL question and based on Improper Instantiation antipattern # How to fix the problem

Here is your pattern:

class HttpInterface
 private static readonly HttpClient client;

 // static initialize
 static HttpInterface()
  // choose one of these depending on your framework
  // HttpClientHandler is an HttpMessageHandler with a common set of properties
  var handler = new HttpClientHandler()
      ServerCertificateCustomValidationCallback = delegate { return true; },
  // derives from HttpClientHandler but adds properties that generally only are available on full .NET
  var handler = new WebRequestHandler()
      ServerCertificateValidationCallback = delegate { return true; },
      ServerCertificateCustomValidationCallback = delegate { return true; },

  client = new HttpClient(handler);
 // in your code use the static client to do your stuff
 var jsonEncoded = new StringContent(someJsonString, Encoding.UTF8, "application/json");

 // here in sync
 using (HttpResponseMessage resultMsg = client.PostAsync(someRequestUrl, jsonEncoded).Result)
  using (HttpContent respContent = resultMsg.Content)
   return respContent.ReadAsStringAsync().Result;

In Go's http package, how do I get the query string on a POST request?

A QueryString is, by definition, in the URL. You can access the URL of the request using req.URL (doc). The URL object has a Query() method (doc) that returns a Values type, which is simply a map[string][]string of the QueryString parameters.

If what you're looking for is the POST data as submitted by an HTML form, then this is (usually) a key-value pair in the request body. You're correct in your answer that you can call ParseForm() and then use req.Form field to get the map of key-value pairs, but you can also call FormValue(key) to get the value of a specific key. This calls ParseForm() if required, and gets values regardless of how they were sent (i.e. in query string or in the request body).

How to pass payload via JSON file for curl?

curl sends POST requests with the default content type of application/x-www-form-urlencoded. If you want to send a JSON request, you will have to specify the correct content type header:

$ curl -vX POST http://server/api/v1/places.json -d @testplace.json \
--header "Content-Type: application/json"

But that will only work if the server accepts json input. The .json at the end of the url may only indicate that the output is json, it doesn't necessarily mean that it also will handle json input. The API documentation should give you a hint on whether it does or not.

The reason you get a 401 and not some other error is probably because the server can't extract the auth_token from your request.

Cleanest way to toggle a boolean variable in Java?

theBoolean ^= true;

Fewer keystrokes if your variable is longer than four letters

Edit: code tends to return useful results when used as Google search terms. The code above doesn't. For those who need it, it's bitwise XOR as described here.

Calculate date from week number

I have made a refined version of the proposed solution that is a simpler and parametrises the firstDayOfWeek:

public static DateTime GetFirstDayOfWeek(int year, int week, DayOfWeek firstDayOfWeek)
    return GetWeek1Day1(year, firstDayOfWeek).AddDays(7 * (week - 1));

public static DateTime GetWeek1Day1(int year, DayOfWeek firstDayOfWeek)
    DateTime date = new DateTime(year, 1, 1);

    // Move towards firstDayOfWeek
    date = date.AddDays(firstDayOfWeek - date.DayOfWeek);

    // Either 1 or 52 or 53
    int weekOfYear = CultureInfo.CurrentCulture.Calendar.GetWeekOfYear(date, CalendarWeekRule.FirstFullWeek, firstDayOfWeek);

    // Move forwards 1 week if week is 52 or 53
    date = date.AddDays(7 * System.Math.Sign(weekOfYear - 1));

    return date;

pip3: command not found but python3-pip is already installed

For Kali, you must use this code after the update.

$sudo python3

or if you write this, it also works but not supported anymore. So don't use:

$sudo python

Resolve Javascript Promise outside function scope

Thanks to everyone who posted in this thread. I created a module that includes the Defer() object described earlier as well as a few other objects built upon it. They all leverage Promises and the neat Promise call-back syntax to implement communication/event handling within a program.

  • Defer: Promise that can be resolved failed remotely (outside of its body)
  • Delay: Promise that is resolved automatically after a given time
  • TimeOut: Promise that fails automatically after a given time.
  • Cycle: Re-triggerable promise to manage events with the Promise syntax
  • Queue: Execution queue based on Promise chaining.

rp = require("openpromise")

MySQL said: Documentation #1045 - Access denied for user 'root'@'localhost' (using password: NO)

Check your MySQL Port number 3306.

Is there any other MySQL Install in your system on same port ?

If any installation found the change the port number to any number between 3301-3309 (except 3306)

user name : root
password : ' ' (Empty)

Force browser to clear cache

A lot of answers are missing the point - most developers are well aware that turning off the cache is inefficient. However, there are many common circumstances where efficiency is unimportant and default cache behavior is badly broken.

These include nested, iterative script testing (the big one!) and broken third party software workarounds. None of the solutions given here are adequate to address such common scenarios. Most web browsers are far too aggressive caching and provide no sensible means to avoid these problems.

postgreSQL - psql \i : how to execute script in a given path

Have you tried using Unix style slashes (/ instead of \)?

\ is often an escape or command character, and may be the source of confusion. I have never had issues with this, but I also do not have Windows, so I cannot test it.

Additionally, the permissions may be based on the user running psql, or maybe the user executing the postmaster service, check that both have read to that file in that directory.

SQL conditional SELECT

Sounds like they want the ability to return only allowed fields, which means the number of fields returned also has to be dynamic. This will work with 2 variables. Anything more than that will be getting confusing.

IF (selectField1 = true AND selectField2 = true)
   SELECT Field1, Field2
   FROM Table
ELSE IF (selectField1 = true)
   SELECT Field1
   FROM Table
ELSE IF (selectField2 = true)
   SELECT Field2
   FROM Table

Dynamic SQL will help with multiples. This examples is assuming atleast 1 column is true.

DECLARE @sql varchar(MAX)
SET @sql = 'SELECT '
IF (selectField1 = true)
   SET @sql = @sql + 'Field1, '
IF (selectField2 = true)
   SET @sql = @sql + 'Field2, '
-- DROP ', '
@sql = SUBSTRING(@sql, 1, LEN(@sql)-2)

SET @sql = @sql + ' FROM Table'


Scrolling an iframe with JavaScript?

You can use the onload event to detect when the iframe has finished loading, and there you can use the scrollTo function on the contentWindow of the iframe, to scroll to a defined position of pixels, from left and top (x, y):

var myIframe = document.getElementById('iframe');
myIframe.onload = function () {

You can check a working example here.

Note: This will work if both pages reside on the same domain.

Read a HTML file into a string variable in memory

var htmlText = System.IO.File.ReadAllText(@"C:/filename.html");

And if file in at application root, user below

var htmlText = System.IO.File.ReadAllText(HttpContext.Current.Server.MapPath(@"~/filename.html"));

Calculate number of hours between 2 dates in PHP

First, you should create an interval object from a range of dates. By the wording used in this sentence alone, one can easily identify basic abstractions needed. There is an interval as a concept, and a couple of more ways to implement it, include the one already mentioned -- from a range of dates. Thus, an interval looks like that:

$interval =
    new FromRange(
        new FromISO8601('2017-02-14T14:27:39+00:00'),
        new FromISO8601('2017-03-14T14:27:39+00:00')

FromISO8601 has the same semantics: it's a datetime object created from iso8601-formatted string, hence the name.

When you have an interval, you can format it however you like. If you need a number of full hours, you can have

(new TotalFullHours($interval))->value();

If you want a ceiled total hours, here you go:

(new TotalCeiledHours($interval))->value();

For more about this approach and some examples, check out this entry.

Check if table exists without using "select from"

A performance comparison:

  • MySQL 5.0.77, on a db that has about 11,000 tables.
  • Selecting a non-recently-used table so it's not cached.
  • Averaged over 10 tries each. (Note: done with different tables to avoid caching).

322ms: show tables like 'table201608';

691ms: select 1 from table201608 limit 1;

319ms: SELECT count(*) FROM information_schema.TABLES WHERE (TABLE_SCHEMA = 'mydb') AND (TABLE_NAME = 'table201608');

Note if you're running this a lot -- like over many HTML requests in a short period -- the 2nd will be way faster since it'll be cached an average 200 ms or faster.

Visual Studio Copy Project

The easiest way to do this would be to export the project as a template and save it to the default template location. Then, copy the template into the exact same directory on the location you want to move it to. After that, open up visual studio on the new location, create a new project, and you will get a prompt to search for a template. Search for whatever you named the template, select it and you're done!

Auto submit form on page load

Add the following to Body tag,

<body onload="document.forms['member_signup'].submit()">

and give name attribute to your Form.

<form method="POST" action="" name="member_signup">

What is the difference between ELF files and bin files?

A Bin file is a pure binary file with no memory fix-ups or relocations, more than likely it has explicit instructions to be loaded at a specific memory address. Whereas....

ELF files are Executable Linkable Format which consists of a symbol look-ups and relocatable table, that is, it can be loaded at any memory address by the kernel and automatically, all symbols used, are adjusted to the offset from that memory address where it was loaded into. Usually ELF files have a number of sections, such as 'data', 'text', 'bss', to name but a is within those sections where the run-time can calculate where to adjust the symbol's memory references dynamically at run-time.

SQL update from one Table to another based on a ID match

update from one table to another table on id matched

     TABLE1 t1, 
     TABLE2 t2
     t1.column_name = t2.column_name 

Is it possible to use Java 8 for Android development?

I wrote a similar answer to a similar question on Stack Overflow, but here is part of that answer.

Android Studio 2.1:

The new version of Android Studio (2.1) has support for Java 8 features. Here is an extract from the Android Developers blogspot post:

... Android Studio 2.1 release includes support for the new Jack compiler and support for Java 8.


To use Java 8 language features when developing with the N Developer Preview, you need to use the Jack compiler. The New Project Wizard [File? New? Project] generates the correct configurations for projects targeting the N.

Prior to Android Studio 2.1:

Android does not support Java 1.8 yet (it only supports up to 1.7), so you cannot use Java 8 features like lambdas.

This answer gives more detail on Android Studio's compatibility; it states:

If you want to use lambdas, one of the major features of Java 8 in Android, you can use gradle-retrolamba

If you want to know more about using gradle-retrolambda, this answer gives a lot of detail on doing that.

Serialize and Deserialize Json and Json Array in Unity

Like @Maximiliangerhardt said, MiniJson do not have the capability to deserialize properly. I used JsonFx and works like a charm. Works with the []

player[] p = JsonReader.Deserialize<player[]>(serviceData);
Debug.Log(p[0].playerId +" "+ p[0].playerLoc+"--"+ p[1].playerId + " " + p[1].playerLoc+"--"+ p[2].playerId + " " + p[2].playerLoc);

How do I configure different environments in Angular.js?

For Gulp users, gulp-ng-constant is also useful combined with gulp-concat, event-stream and yargs.

var concat = require('gulp-concat'),
    es = require('event-stream'),
    gulp = require('gulp'),
    ngConstant = require('gulp-ng-constant'),
    argv = require('yargs').argv;

var enviroment = argv.env || 'development';

gulp.task('config', function () {
  var config = gulp.src('config/' + enviroment + '.json')
    .pipe(ngConstant({name: 'app.config'}));
  var scripts = gulp.src('js/*');
  return es.merge(config, scripts)
    .on('error', function() { });

In my config folder I have these files:

ls -l config
total 8
-rw-r--r--+ 1 .. ci.json
-rw-r--r--+ 1 .. development.json
-rw-r--r--+ 1 .. production.json

Then you can run gulp config --env development and that will create something like this:

angular.module("app.config", [])
.constant("foo", "bar")
.constant("ngConstant", true);

I also have this spec:


it('loads the config', inject(function(config) {

How to configure SMTP settings in web.config

Set IIS to forward your mail to the remote server. The specifics vary greatly depending on the version of IIS. For IIS 7.5:

  1. Open IIS Manager
  2. Connect to your server if needed
  3. Select the server node; you should see an SMTP option on the right in the ASP.NET section
  4. Double-click the SMTP icon.
  5. Select the "Deliver e-mail to SMTP server" option and enter your server name, credentials, etc.

Show/hide image with JavaScript

This is working code:

  <body bgcolor=cyan>
    <img src ="backgr1.JPG" id="my" width="310" height="392" style="position: absolute; top:92px; left:375px; visibility:hidden"/>
    <script type="text/javascript">
      function tend() {
      function tn() {
    <input type="button" onclick="tend()" value="back">
    <input type="button" onclick="tn()" value="close">


Thanks HansUp for your answer, it is very helpful and it works!

I found three patterns working in Access, yours is the best, because it works in all cases.

  • INNER JOIN, your variant. I will call it "closed set pattern". It is possible to join more than two tables to the same table with good performance only with this pattern.

    SELECT C_Name, cr.P_FirstName+" "+cr.P_SurName AS ClassRepresentativ, cr2.P_FirstName+" "+cr2.P_SurName AS ClassRepresentativ2nd
           INNER JOIN person AS cr 
           ON class.C_P_ClassRep=cr.P_Nr
         INNER JOIN person AS cr2
         ON class.C_P_ClassRep2nd=cr2.P_Nr


  • INNER JOIN "chained-set pattern"

    SELECT C_Name, cr.P_FirstName+" "+cr.P_SurName AS ClassRepresentativ, cr2.P_FirstName+" "+cr2.P_SurName AS ClassRepresentativ2nd
    FROM person AS cr
    INNER JOIN ( class 
       INNER JOIN ( person AS cr2
       ) ON class.C_P_ClassRep2nd=cr2.P_Nr
    ) ON class.C_P_ClassRep=cr.P_Nr

    SELECT C_Name, cr.P_FirstName+" "+cr.P_SurName AS ClassRepresentativ, cr2.P_FirstName+" "+cr2.P_SurName AS ClassRepresentativ2nd
    FROM class, person AS cr, person AS cr2
    WHERE class.C_P_ClassRep=cr.P_Nr AND class.C_P_ClassRep2nd=cr2.P_Nr

How to mount host volumes into docker containers in Dockerfile during build

There is a way to mount a volume during a build, but it doesn't involve Dockerfiles.

The technique would be to create a container from whatever base you wanted to use (mounting your volume(s) in the container with the -v option), run a shell script to do your image building work, then commit the container as an image when done.

Not only will this leave out the excess files you don't want (this is good for secure files as well, like SSH files), it also creates a single image. It has downsides: the commit command doesn't support all of the Dockerfile instructions, and it doesn't let you pick up when you left off if you need to edit your build script.


For example,

CONTAINER_ID=$(docker run -dit ubuntu:16.04)
docker cp $CONTAINER_ID:/
docker exec -t $CONTAINER_ID /bin/sh -c '/bin/sh /'
docker commit $CONTAINER_ID $REPO:$TAG
docker stop $CONTAINER_ID

Socket send and receive byte array

First, do not use DataOutputStream unless it’s really necessary. Second:

Socket socket = new Socket("host", port);
OutputStream socketOutputStream = socket.getOutputStream();

Of course this lacks any error checking but this should get you going. The JDK API Javadoc is your friend and can help you a lot.

How do I specify different layouts for portrait and landscape orientations?

Just a reminder:

Remove orientation from android:configChanges attribute for the activity in your manifest xml file if you defined it:


How to start a Process as administrator mode in C#

 Process proc = new Process();                                                              
                   ProcessStartInfo info = 
                   new ProcessStartInfo("Your Process name".exe, "Arguments");
                   info.WindowStyle = ProcessWindowStyle.Hidden;
                   info.UseShellExecute =true;
                   info.Verb ="runas";
                   proc.StartInfo = info;

How to programmatically get iOS status bar height

Swift 3 or Swift 4:


How to advance to the next form input when the current input has a value?

you just need to give focus to the next input field (by invoking focus()method on that input element), for example if you're using jQuery this code will simulate the tab key when enter is pressed:

var inputs = $(':input').keypress(function(e){ 
    if (e.which == 13) {
       var nextInput = inputs.get(inputs.index(this) + 1);
       if (nextInput) {

Adding external library into Qt Creator project

Are you using qmake projects? If so, you can add an external library using the LIBS variable. E.g:

win32:LIBS += path/to/Psapi.lib

Where is the file in a Spring Boot project?

You can create it manually but the default location of is here

enter image description here

Android Push Notifications: Icon not displaying in notification, white square shown instead

I really suggest following Google's Design Guidelines:

which says "Notification icons must be entirely white."

Problems with installation of Google App Engine SDK for php in OS X

It's likely that the download was corrupted if you are getting an error with the disk image. Go back to the downloads page at and look at the SHA1 checksum. Then, go to your Terminal app on your mac and run the following:

openssl sha1 [put the full path to the file here without brackets] 

For example:

openssl sha1 /Users/me/Desktop/myFile.dmg 

If you get a different value than the one on the Downloads page, you know your file is not properly downloaded and you should try again.

How can I compare strings in C using a `switch` statement?

This is generally how I do it.

void order_plane(const char *p)
    switch ((*p) * 256 + *(p+1))
        case 0x4231 : /* B1 */
           printf("Yes, order this bomber.  It's a blast.\n");

        case 0x5354 : /* ST */
            printf("Nah.  I just can't see this one.\n");

        default :
            printf("Not today.  Can I interest you in a crate of SAMs?\n";

SmartGit Installation and Usage on Ubuntu

Now on the Smartgit webpage (I don't know since when) there is the possibility to download directly the .deb package. Once installed, it will upgrade automagically itself when a new version is released.

Given the lat/long coordinates, how can we find out the city/country?

You can use Google Geocoding API

Bellow is php function that returns Adress, City, State and Country

public function get_location($latitude='', $longitude='')
    $geolocation = $latitude.','.$longitude;
    $request = ''.$geolocation.'&sensor=false'; 
    $file_contents = file_get_contents($request);
    $json_decode = json_decode($file_contents);
    if(isset($json_decode->results[0])) {
        $response = array();
        foreach($json_decode->results[0]->address_components as $addressComponet) {
            if(in_array('political', $addressComponet->types)) {
                    $response[] = $addressComponet->long_name; 

        if(isset($response[0])){ $first  =  $response[0];  } else { $first  = 'null'; }
        if(isset($response[1])){ $second =  $response[1];  } else { $second = 'null'; } 
        if(isset($response[2])){ $third  =  $response[2];  } else { $third  = 'null'; }
        if(isset($response[3])){ $fourth =  $response[3];  } else { $fourth = 'null'; }
        if(isset($response[4])){ $fifth  =  $response[4];  } else { $fifth  = 'null'; }

        $loc['address']=''; $loc['city']=''; $loc['state']=''; $loc['country']='';
        if( $first != 'null' && $second != 'null' && $third != 'null' && $fourth != 'null' && $fifth != 'null' ) {
            $loc['address'] = $first;
            $loc['city'] = $second;
            $loc['state'] = $fourth;
            $loc['country'] = $fifth;
        else if ( $first != 'null' && $second != 'null' && $third != 'null' && $fourth != 'null' && $fifth == 'null'  ) {
            $loc['address'] = $first;
            $loc['city'] = $second;
            $loc['state'] = $third;
            $loc['country'] = $fourth;
        else if ( $first != 'null' && $second != 'null' && $third != 'null' && $fourth == 'null' && $fifth == 'null' ) {
            $loc['city'] = $first;
            $loc['state'] = $second;
            $loc['country'] = $third;
        else if ( $first != 'null' && $second != 'null' && $third == 'null' && $fourth == 'null' && $fifth == 'null'  ) {
            $loc['state'] = $first;
            $loc['country'] = $second;
        else if ( $first != 'null' && $second == 'null' && $third == 'null' && $fourth == 'null' && $fifth == 'null'  ) {
            $loc['country'] = $first;
      return $loc;

MySQL: #126 - Incorrect key file for table

mysql> set global sql_slave_skip_counter=1; start slave; show slave status\G

Then got error exists :

 Error 'Table './openx/f_scraper_banner_details' is marked as crashed and should be repaired' on query. Default database: 'openx'. Query: 'INSERT INTO f_scraper_banner_details(job_details_id, ad_id, client_id, zone_id, affiliateid, comments, pct_to_report, publisher_currency, sanity_check_enabled, status, error_code, report_date) VALUES (10274859, 321264, 0, 31926, 0, '', -1, 'USD', 1, 'FAILURE', 'INACTIVE_BANNER', '2016-06-28 04:00:00')'
 mysql> repair table f_scraper_banner_details;

This worked for me

How to add a linked source folder in Android Studio?

in your build.gradle add the following to the end of the android node

android {

    sourceSets { += 'src/main/<YOUR DIRECTORY>'


how to make negative numbers into positive

floor a;
floor b;
a = -0.340515;

so what to do?

b = 65565 +a;
a = 65565 -b;


if(a < 0){
a = 65565-(65565+a);}

An exception of type 'System.Data.SqlClient.SqlException' occurred in System.Data.dll

Try this

SqlCommand cmd = new SqlCommand("SELECT EmpName FROM Employee WHERE EmpID=@id", con);
cmd.Parameters.AddWithValue("id", id.Text);

JQuery datepicker language

Here is example how you can do localization by yourself.

jQuery(function($) {_x000D_
    duration: '',_x000D_
    changeMonth: false,_x000D_
    changeYear: false,_x000D_
    yearRange: '2010:2020',_x000D_
    showTime: false,_x000D_
    time24h: true_x000D_
  $.datepicker.regional['cs'] = {_x000D_
    closeText: 'Zavrít',_x000D_
    prevText: '&#x3c;Dríve',_x000D_
    nextText: 'Pozdeji&#x3e;',_x000D_
    currentText: 'Nyní',_x000D_
    monthNames: ['leden', 'únor', 'brezen', 'duben', 'kveten', 'cerven', 'cervenec', 'srpen',_x000D_
      'zárí', 'ríjen', 'listopad', 'prosinec'_x000D_
    monthNamesShort: ['led', 'úno', 'bre', 'dub', 'kve', 'cer', 'cvc', 'srp', 'zár', 'ríj', 'lis', 'pro'],_x000D_
    dayNames: ['nedele', 'pondelí', 'úterý', 'streda', 'ctvrtek', 'pátek', 'sobota'],_x000D_
    dayNamesShort: ['ne', 'po', 'út', 'st', 'ct', 'pá', 'so'],_x000D_
    dayNamesMin: ['ne', 'po', 'út', 'st', 'ct', 'pá', 'so'],_x000D_
    weekHeader: 'Týd',_x000D_
    dateFormat: 'dd/mm/yy',_x000D_
    firstDay: 1,_x000D_
    isRTL: false,_x000D_
    showMonthAfterYear: false,_x000D_
    yearSuffix: ''_x000D_
<!DOCTYPE html>_x000D_
  <script src=""></script>_x000D_
  <link data-require="jqueryui@*" data-semver="1.10.0" rel="stylesheet" href="//" />_x000D_
  <script data-require="jqueryui@*" data-semver="1.10.0" src="//"></script>_x000D_
  <script src="datepicker-cs.js"></script>_x000D_
  <script type="text/javascript">_x000D_
    $(document).ready(function() {_x000D_
        dateFormat: "dd.m.yy",_x000D_
        minDate: 0,_x000D_
        showOtherMonths: true,_x000D_
        firstDay: 1_x000D_
  <h1>Here is your datepicker</h1>_x000D_
  <input id="test" type="text" />_x000D_

How to fit Windows Form to any screen resolution?

You can simply set the window state

this.WindowState = System.Windows.Forms.FormWindowState.Maximized;

How do I encode URI parameter values?

I don't have enough reputation to comment on answers, but I just wanted to note that downloading the JSR-311 api by itself will not work. You need to download the reference implementation (jersey).

Only downloading the api from the JSR page will give you a ClassNotFoundException when the api tries to look for an implementation at runtime.

Difference between long and int data types

A typical best practice is not using long/int/short directly. Instead, according to specification of compilers and OS, wrap them into a header file to ensure they hold exactly the amount of bits that you want. Then use int8/int16/int32 instead of long/int/short. For example, on 32bit Linux, you could define a header like this

typedef char int8;
typedef short int16;
typedef int int32;
typedef unsigned int uint32;

Difference between os.getenv and os.environ.get

While there is no functional difference between os.environ.get and os.getenv, there is a massive difference between os.putenv and setting entries on os.environ. os.putenv is broken, so you should default to os.environ.get simply to avoid the way os.getenv encourages you to use os.putenv for symmetry.

os.putenv changes the actual OS-level environment variables, but in a way that doesn't show up through os.getenv, os.environ, or any other stdlib way of inspecting environment variables:

>>> import os
>>> os.environ['asdf'] = 'fdsa'
>>> os.environ['asdf']
>>> os.putenv('aaaa', 'bbbb')
>>> os.getenv('aaaa')
>>> os.environ.get('aaaa')

You'd probably have to make a ctypes call to the C-level getenv to see the real environment variables after calling os.putenv. (Launching a shell subprocess and asking it for its environment variables might work too, if you're very careful about escaping and --norc/--noprofile/anything else you need to do to avoid startup configuration, but it seems a lot harder to get right.)

How can I declare and define multiple variables in one line using C++?

As @Josh said, the correct answer is:

int column = 0,
    row = 0,
    index = 0;

You'll need to watch out for the same thing with pointers. This:

int* a, b, c;

Is equivalent to:

int *a;
int b;
int c;

Code for a simple JavaScript countdown timer?

So far the answers seem to rely on code being run instantly. If you set a timer for 1000ms, it will actually be around 1008 instead.

Here is how you should do it:

function timer(time,update,complete) {
    var start = new Date().getTime();
    var interval = setInterval(function() {
        var now = time-(new Date().getTime()-start);
        if( now <= 0) {
        else update(Math.floor(now/1000));
    },100); // the smaller this number, the more accurate the timer will be

To use, call:

    5000, // milliseconds
    function(timeleft) { // called every step to update the visible countdown
        document.getElementById('timer').innerHTML = timeleft+" second(s)";
    function() { // what to do after
        alert("Timer complete!");

HTML input textbox with a width of 100% overflows table cells

The problem has been explained previously so I will only reiterate: width doesn't take into account border and padding. One possible answer to this not discussed but which I have found helped me out a bunch is to wrap your inputs. Here's the code, and I'll explain how this helps in a second:

    <td><div style="overflow:hidden"><input style="width:100%" type="text" name="name" value="hello world" /></div></td>

The DIV wrapping the INPUT has no padding nor does it have a border. This is the solution. A DIV will expand to its container's size, but it will also respect border and padding. Now, the INPUT will have no issue expanding to the size of its container since it is border-less and pad-less. Also note that the DIV has its overflow set to hidden. It seems that by default items can fall outside of their container with the default overflow of visible. This just ensures that the input stays inside its container and doesn't attempt to poke through.

I've tested this in Chrome and in Fire Fox. Both seem to respect this solution well.

UPDATE: Since I just got a random downvote, I would like to say that a better way to deal with overflow is with the CSS3 box-sizing attribute as described by pricco:

.myinput {
    -moz-box-sizing: border-box;
    -webkit-box-sizing: border-box;
    -ms-box-sizing: border-box;
    -o-box-sizing: border-box;
    box-sizing: border-box;

This seems to be pretty well supported by the major browsers and isn't "hacky" like the overflow trick. There are, however, some minor issues on current browsers with this approach (see Known Issues).

Could not find main class HelloWorld

Just remove your "classpath" from you environment variable. Then try running:

java HelloWorld 

This should work fine.

Angular2 handling http response

The service :

import 'rxjs/add/operator/map';

import { Http } from '@angular/http';
import { Observable } from "rxjs/Rx"
import { Injectable } from '@angular/core';

export class ItemService {
  private api = "your_api_url";

  constructor(private http: Http) {


  toSaveItem(item) {
    return new Promise((resolve, reject) => {
        .post(this.api + '/items', { item: item })
        .map(res => res.json())
        // This catch is very powerfull, it can catch all errors
        .catch((err: Response) => {
          // The err.statusText is empty if server down (err.type === 3)
          console.log((err.statusText || "Can't join the server."));
          // Really usefull. The app can't catch this in "(err)" closure
          reject((err.statusText || "Can't join the server."));
          // This return is required to compile but unuseable in your app
          return Observable.throw(err);
        // The (err) => {} param on subscribe can't catch server down error so I keep only the catch
        .subscribe(data => { resolve(data) })

In the app :

  (res) => { console.log('success', res) },
  (err) => { console.log('error', err) }

Passing A List Of Objects Into An MVC Controller Method Using jQuery Ajax

The only way I could get this to work is to pass the JSON as a string and then deserialise it using JavaScriptSerializer.Deserialize<T>(string input), which is pretty strange if that's the default deserializer for MVC 4.

My model has nested lists of objects and the best I could get using JSON data is the uppermost list to have the correct number of items in it, but all the fields in the items were null.

This kind of thing should not be so hard.

        type: 'POST',
        url: '/Agri/Map/SaveSelfValuation',
        data: { json: JSON.stringify(model) },
        dataType: 'text',
        success: function (data) {

    public JsonResult DoSomething(string json)
        var model = new JavaScriptSerializer().Deserialize<Valuation>(json);

The view 'Index' or its master was not found.

Add the following code in the Application_Start() method inside your project:

ViewEngines.Engines.Add(new RazorViewEngine());

How to POST request using RestSharp

I added this helper method to handle my POST requests that return an object I care about.

For REST purists, I know, POSTs should not return anything besides a status. However, I had a large collection of ids that was too big for a query string parameter.

Helper Method:

    public TResponse Post<TResponse>(string relativeUri, object postBody) where TResponse : new()
        //Note: Ideally the RestClient isn't created for each request. 
        var restClient = new RestClient("http://localhost:999");

        var restRequest = new RestRequest(relativeUri, Method.POST)
            RequestFormat = DataFormat.Json


        var result = restClient.Post<TResponse>(restRequest);

        if (!result.IsSuccessful)
            throw new HttpException($"Item not found: {result.ErrorMessage}");

        return result.Data;


    public List<WhateverReturnType> GetFromApi()
        var idsForLookup = new List<int> {1, 2, 3, 4, 5};

        var relativeUri = "/api/idLookup";

        var restResponse = Post<List<WhateverReturnType>>(relativeUri, idsForLookup);

        return restResponse;

SQL Server 2000: How to exit a stored procedure?

Put it in a TRY/CATCH.

When RAISERROR is run with a severity of 11 or higher in a TRY block, it transfers control to the associated CATCH block

Reference: MSDN.

EDIT: This works for MSSQL 2005+, but I see that you now have clarified that you are working on MSSQL 2000. I'll leave this here for reference.

Creating a BAT file for python script

Just simply open a batch file that contains this two lines in the same folder of your python script:

How can I see if a Perl hash already has a certain key?

Well, your whole code can be limited to:

foreach $line (@lines){
        $strings{$1}++ if $line =~ m|my regex|;

If the value is not there, ++ operator will assume it to be 0 (and then increment to 1). If it is already there - it will simply be incremented.

How to obtain image size using standard Python class (without using external library)?

If you happen to have ImageMagick installed, then you can use 'identify'. For example, you can call it like this:

path = "//folder/image.jpg"
dim = subprocess.Popen(["identify","-format","\"%w,%h\"",path], stdout=subprocess.PIPE).communicate()[0]
(width, height) = [ int(x) for x in re.sub('[\t\r\n"]', '', dim).split(',') ]

Missing Maven dependencies in Eclipse project

For the following steps worked in my case:

1 On eclipse, right click on the desired project Maven -> Disable Maven Nature

2 Right click again then go to Properties. Delete every evidence of external Maven dependency leaving only JRE System Library.

3 Right click one more time on the project then go to Configure -> Convert to Maven Project

it worked for me also

Simple way to transpose columns and rows in SQL?

I'd like to point out few more solutions to transposing columns and rows in SQL.

The first one is - using CURSOR. Although the general consensus in the professional community is to stay away from SQL Server Cursors, there are still instances whereby the use of cursors is recommended. Anyway, Cursors present us with another option to transpose rows into columns.

  • Vertical expansion

    Similar to the PIVOT, the cursor has the dynamic capability to append more rows as your dataset expands to include more policy numbers.

  • Horizontal expansion

    Unlike the PIVOT, the cursor excels in this area as it is able to expand to include newly added document, without altering the script.

  • Performance breakdown

    The major limitation of transposing rows into columns using CURSOR is a disadvantage that is linked to using cursors in general – they come at significant performance cost. This is because the Cursor generates a separate query for each FETCH NEXT operation.

Another solution of transposing rows into columns is by using XML.

The XML solution to transposing rows into columns is basically an optimal version of the PIVOT in that it addresses the dynamic column limitation.

The XML version of the script addresses this limitation by using a combination of XML Path, dynamic T-SQL and some built-in functions (i.e. STUFF, QUOTENAME).

  • Vertical expansion

    Similar to the PIVOT and the Cursor, newly added policies are able to be retrieved in the XML version of the script without altering the original script.

  • Horizontal expansion

    Unlike the PIVOT, newly added documents can be displayed without altering the script.

  • Performance breakdown

    In terms of IO, the statistics of the XML version of the script is almost similar to the PIVOT – the only difference is that the XML has a second scan of dtTranspose table but this time from a logical read – data cache.

You can find some more about these solutions (including some actual T-SQL exmaples) in this article:

How to print an exception in Python?

One has pretty much control on which information from the traceback to be displayed/logged when catching exceptions.

The code

with open("not_existing_file.txt", 'r') as text:

would produce the following traceback:

Traceback (most recent call last):
  File "", line 19, in <module>
    with open("not_existing_file.txt", 'r') as text:
FileNotFoundError: [Errno 2] No such file or directory: 'not_existing_file.txt'

Print/Log the full traceback

As others already mentioned, you can catch the whole traceback by using the traceback module:

import traceback
    with open("not_existing_file.txt", 'r') as text:
except Exception as exception:

This will produce the following output:

Traceback (most recent call last):
  File "", line 19, in <module>
    with open("not_existing_file.txt", 'r') as text:
FileNotFoundError: [Errno 2] No such file or directory: 'not_existing_file.txt'

You can achieve the same by using logging:

    with open("not_existing_file.txt", 'r') as text:
except Exception as exception:
    logger.error(exception, exc_info=True)


__main__: 2020-05-27 12:10:47-ERROR- [Errno 2] No such file or directory: 'not_existing_file.txt'
Traceback (most recent call last):
  File "", line 27, in <module>
    with open("not_existing_file.txt", 'r') as text:
FileNotFoundError: [Errno 2] No such file or directory: 'not_existing_file.txt'

Print/log error name/message only

You might not be interested in the whole traceback, but only in the most important information, such as Exception name and Exception message, use:

    with open("not_existing_file.txt", 'r') as text:
except Exception as exception:
    print("Exception: {}".format(type(exception).__name__))
    print("Exception message: {}".format(exception))


Exception: FileNotFoundError
Exception message: [Errno 2] No such file or directory: 'not_existing_file.txt'

error: use of deleted function

I encountered this error when inheriting from an abstract class and not implementing all of the pure virtual methods in my subclass.

Returning JSON object from an ASP.NET page

In your Page_Load you will want to clear out the normal output and write your own, for example:

string json = "{\"name\":\"Joe\"}";
Response.ContentType = "application/json; charset=utf-8";

To convert a C# object to JSON you can use a library such as Json.NET.

Instead of getting your .aspx page to output JSON though, consider using a Web Service (asmx) or WCF, both of which can output JSON.

Getting data from Yahoo Finance

To your first question, you can't really do any query through YQL to get data for all companies. It's more oriented towards obtaining data for a smaller query. (I.e., it's not going to give you a full data dump of the whole Yahoo! Finance database.)

To your second question, here's how you can get started exploring the Yahoo! Finance tables in YQL:

  1. Start at the YQL Console
  2. In the upper left corner, make sure Show Community Tables is checked
  3. Type finance in the search field
  4. You'll see all the Yahoo Finance tables (about 15)

Then you can try some example queries like the following:

select * from where symbol in ("YHOO","AAPL","GOOG","MSFT")

Update 2016-04-04: Here's a current screenshot showing the location of the Show Community Tables checkbox which must be clicked to see these finance tables: enter image description here

Unexpected 'else' in "else" error

You need to rearrange your curly brackets. Your first statement is complete, so R interprets it as such and produces syntax errors on the other lines. Your code should look like:

if (dsnt<0.05) {
} else if (dst<0.05) {
} else {

To put it more simply, if you have:

if(condition == TRUE) x <- TRUE
else x <- FALSE

Then R reads the first line and because it is complete, runs that in its entirety. When it gets to the next line, it goes "Else? Else what?" because it is a completely new statement. To have R interpret the else as part of the preceding if statement, you must have curly brackets to tell R that you aren't yet finished:

if(condition == TRUE) {x <- TRUE
 } else {x <- FALSE}

How to change JFrame icon

This did the trick in my case super or this referes to JFrame in my class

URL url = getClass().getResource("gfx/hi_20px.png");
ImageIcon imgicon = new ImageIcon(url);

How to POST a FORM from HTML to ASPX page

You sure can.

The easiest way to see how you might do this is to browse to the aspx page you want to post to. Then save the source of that page as HTML. Change the action of the form on your new html page to point back to the aspx page you originally copied it from.

Add value tags to your form fields and put the data you want in there, then open the page and hit the submit button.

How to run multiple DOS commands in parallel?

You can execute commands in parallel with start like this:

start "" ping myserver
start "" nslookup myserver
start "" morecommands

They will each start in their own command prompt and allow you to run multiple commands at the same time from one batch file.

Hope this helps!

Laravel PDOException SQLSTATE[HY000] [1049] Unknown database 'forge'

Sounds like you have an environment-specific config file somewhere that overrides the default database settings. Possibly app/config/local/database.php.

How can I get the source directory of a Bash script from within the script itself?

The shortest and most elegant way to do this is:

DIRECTORY=$(cd `dirname $0` && pwd)

This would work on all platforms and is super clean.

More details can be found in "Which directory is that bash script in?".

Using Tempdata in ASP.NET MVC - Best practice

Just be aware of TempData persistence, it's a bit tricky. For example if you even simply read TempData inside the current request, it would be removed and consequently you don't have it for the next request. Instead, you can use Peek method. I would recommend reading this cool article:

MVC Tempdata , Peek and Keep confusion

How to hide navigation bar permanently in android activity?

I think this code will resolve your issue. Copy and paste this code on your

protected void onCreate(Bundle savedInstanceState) {                          

    View decorView = getWindow().getDecorView();
    (new View.OnSystemUiVisibilityChangeListener() {
        public void onSystemUiVisibilityChange(int visibility) {

            if ((visibility & View.SYSTEM_UI_FLAG_FULLSCREEN) == 0) {

private void hideNavigationBar() {

It will works on Android-10. I hope it will helps.

Convert a number range to another range, maintaining ratio

List comprehension one liner solution

color_array_new = [int((((x - min(node_sizes)) * 99) / (max(node_sizes) - min(node_sizes))) + 1) for x in node_sizes]

Longer version

def colour_specter(waste_amount):
color_array = []
OldRange = max(waste_amount) - min(waste_amount)
NewRange = 99
for number_value in waste_amount:
    NewValue = int((((number_value - min(waste_amount)) * NewRange) / OldRange) + 1)
return color_array

PHP syntax question: What does the question mark and colon mean?

This is the PHP ternary operator (also known as a conditional operator) - if first operand evaluates true, evaluate as second operand, else evaluate as third operand.

Think of it as an "if" statement you can use in expressions. Can be very useful in making concise assignments that depend on some condition, e.g.

$param = isset($_GET['param']) ? $_GET['param'] : 'default';

There's also a shorthand version of this (in PHP 5.3 onwards). You can leave out the middle operand. The operator will evaluate as the first operand if it true, and the third operand otherwise. For example:

$result = $x ?: 'default';

It is worth mentioning that the above code when using i.e. $_GET or $_POST variable will throw undefined index notice and to prevent that we need to use a longer version, with isset or a null coalescing operator which is introduced in PHP7:

$param = $_GET['param'] ?? 'default';

SQL Server Management Studio – tips for improving the TSQL coding process

If you need to write a lot of sprocs for an API of some sort. You may like this tools I wrote when I was a programmer. Say you have a 200 columns table that need to have a sproc written to insert/update and another one to delete. Because you don't want your application to directly access the tables. Just the declaration part will be a tedious task but not if a part of the code is written for you. Here's an example...

CREATE PROC upsert_Table1(@col1 int, @col2 varchar(200), @col3 float, etc.)
  UPDATE table1 SET col1 = @col1, col2 = @col2, col3 = @col3, etc.
  IF @@error <> 0
    INSERT Table1 (col1, col2, col3, etc.)
    VALUES(@col1, @col2, @col3, etc.)
CREATE PROC delete_Table1(@col1)
AS DELETE FROM Table1 WHERE col1 = @col1

Note : You can also get to the original code and article written in 2002 (I feel old now!)

What is the T-SQL syntax to connect to another SQL Server?

Update: for connecting to another sql server and executing sql statements, you have to use sqlcmd Utility. This is typically done in a batch file. You can combine this with xmp_cmdshell if you want to execute it within management studio.

one way is to configure a linked server. then you can append the linked server and the database name to the table name. (select * from linkedserver.database.dbo.TableName)

USE master
EXEC sp_addlinkedserver 
    N'SQL Server'

Installed Java 7 on Mac OS X but Terminal is still using version 6

Check JDK versions installed:

$ ls  /Library/Java/JavaVirtualMachines/
jdk-11.0.2.jdk  jdk1.8.0_91.jdk

Now in your ~/.bashrc export JAVA_HOME specifying the version:

if [ -e /usr/libexec/java_home ]; then
  export JAVA_HOME=$(/usr/libexec/java_home -v 11)

Source the bashrc file and the Java version will be updated:

$ java -version
java version "11.0.2" 2019-01-15 LTS
Java(TM) SE Runtime Environment 18.9 (build 11.0.2+9-LTS)
Java HotSpot(TM) 64-Bit Server VM 18.9 (build 11.0.2+9-LTS, mixed mode)

Simple linked list in C++



using namespace std;

struct Node
    int num;
    Node *next;

Node *head = NULL;
Node *tail = NULL;

void AddnodeAtbeggining(){
    Node *temp = new Node;
    cout << "Enter the item";
    cin >> temp->num;
    temp->next = NULL;
    if (head == NULL)
        head = temp;
        tail = temp;
        temp->next = head;
        head = temp;

void addnodeAtend()
    Node *temp = new Node;
    cout << "Enter the item";
    cin >> temp->num;
    temp->next = NULL;
    if (head == NULL){
        head = temp;
        tail = temp;
        tail->next = temp;
        tail = temp;

void displayNode()
    cout << "\nDisplay Function\n";
    Node *temp = head;
    for(Node *temp = head; temp != NULL; temp = temp->next)
        cout << temp->num << ",";

void deleteNode ()
    for (Node *temp = head; temp != NULL; temp = temp->next)
        delete head;

int main ()

Why am I getting "void value not ignored as it ought to be"?

    int a = srand(time(NULL))
        arr[i] = a;

Should be

        arr[i] = rand();

And put srand(time(NULL)) somewhere at the very beginning of your program.

How to define an enum with string value?

A class that emulates enum behaviour but using string instead of int can be created as follows...

public class GrainType
    private string _typeKeyWord;

    private GrainType(string typeKeyWord)
        _typeKeyWord = typeKeyWord;

    public override string ToString()
        return _typeKeyWord;

    public static GrainType Wheat = new GrainType("GT_WHEAT");
    public static GrainType Corn = new GrainType("GT_CORN");
    public static GrainType Rice = new GrainType("GT_RICE");
    public static GrainType Barley = new GrainType("GT_BARLEY");



GrainType myGrain = GrainType.Wheat;



public void PrintGrainKeyword(GrainType grain) 
    Console.Writeline("My Grain code is " + grain.ToString());   // Displays "My Grain code is GT_WHEAT"

Defining and using a variable in batch file

input location.bat

@echo off

set /p "location"="bob"
echo We're working with %location%


We're working with bob

(mistakes u done : space and " ")

Resizing UITableView to fit content

I've tried this in iOS 7 and it worked for me

- (void)viewDidLoad
    [super viewDidLoad];
    [self.tableView sizeToFit];

Add vertical scroll bar to panel

Add to your panel's style code something like this:

<asp:Panel ID="myPanel" runat="Server" CssClass="myPanelCSS" style="overflow-y:auto; overflow-x:hidden"></asp:Panel>

Generate UML Class Diagram from Java Project

How about the Omondo Plugin for Eclipse. I have used it and I find it to be quite useful. Although if you are generating diagrams for large sources, you might have to start Eclipse with more memory.

Displaying files (e.g. images) stored in Google Drive on a website

For images, open an image in google viewer. i.e.

Method 1

then view source> find word "texmex-thumb" and aside it there will be link.

Setting a divs background image to fit its size?

You can achieve this with the background-size property, which is now supported by most browsers.

To scale the background image to fit inside the div:

background-size: contain;

To scale the background image to cover the whole div:

background-size: cover;

Nginx: Permission denied for nginx on Ubuntu

Permission to view log files is granted to users being in the group adm.

To add a user to this group on the command line issue:

sudo usermod -aG adm <USER>

How can I completely remove TFS Bindings

You could try using this tool which automatically removes the Team Foundation Bindings from a project.