Programs & Examples On #Quickbooks online

Import a file from a subdirectory?

Try import .lib.BoxTime. For more information read about relative import in PEP 328.

ALTER TABLE add constraint

Omit the parenthesis:

    ADD CONSTRAINT userProperties
    FOREIGN KEY(properties)
    REFERENCES Properties(ID)

How can I represent a range in Java?

import java.util.Arrays;

class Soft{
    public static void main(String[] args){
        int[] nums=range(9, 12);
    static int[] range(int low, int high){
        int[] a=new int[high-low];
        for(int i=0,j=low;i<high-low;i++,j++){
        return a;


My code is similar to Python`s range :)

Why doesn't Python have multiline comments?

This likely goes back to the core concept that there should be one obvious way to do a task. Additional comment styles add unnecessary complications and could decrease readability.

Error inflating when extending a class

@Tim - Both the constructors are not required, only the ViewClassName(Context context, AttributeSet attrs ) constructor is necessary. I found this out the painful way, after hours and hours of wasted time.

I am very new to Android development, but I am making a wild guess here, that it maybe due to the fact that since we are adding the custom View class in the XML file, we are setting several attributes to it in the XML, which needs to be processed at the time of instantiation. Someone far more knowledgeable than me will be able to shed clearer light on this matter though.

How to convert HTML to PDF using iTextSharp

As of 2018, there is also iText7 (A next iteration of old iTextSharp library) and its HTML to PDF package available: itext7.pdfhtml

Usage is straightforward:

    new FileInfo(@"Path\to\Html\File.html"),
    new FileInfo(@"Path\to\Pdf\File.pdf")

Method has many more overloads.

Update: iText* family of products has dual licensing model: free for open source, paid for commercial use.

Using an attribute of the current class instance as a default value for method's parameter

Default value for parameters are evaluated at "compilation", once. So obviously you can't access self. The classic example is list as default parameter. If you add elements into it, the default value for the parameter changes!

The workaround is to use another default parameter, typically None, and then check and update the variable.

Execute a command in command prompt using excel VBA

The S parameter does not do anything on its own.

/S      Modifies the treatment of string after /C or /K (see below) 
/C      Carries out the command specified by string and then terminates  
/K      Carries out the command specified by string but remains  

Try something like this instead

Call Shell("cmd.exe /S /K" & "perl c:\temp", vbNormalFocus)

You may not even need to add "cmd.exe" to this command unless you want a command window to open up when this is run. Shell should execute the command on its own.

Shell("perl c:\temp")

To wait for the command to finish you will have to do something like @Nate Hekman shows in his answer here

Dim wsh As Object
Set wsh = VBA.CreateObject("WScript.Shell")
Dim waitOnReturn As Boolean: waitOnReturn = True
Dim windowStyle As Integer: windowStyle = 1

wsh.Run "cmd.exe /S /C perl c:\temp", windowStyle, waitOnReturn

Setting default checkbox value in Objective-C?

Documentation on UISwitch says:

[mySwitch setOn:NO]; 

In Interface Builder, select your switch and in the Attributes inspector you'll find State which can be set to on or off.

"ImportError: no module named 'requests'" after installing with pip

Opening CMD in the location of the already installed request folder and running "pip install requests" worked for me. I am using two different versions of Python.

I think this works because requests is now installed outside my virtual environment. Haven't checked but just thought I'd write this in, in case anyone else is going crazy searching on Google.

remote rejected master -> master (pre-receive hook declined)

Mine finally worked somewhere along this road:

  1. Updating Git
  2. back to \my_first_rail_app\, type or run:
    • a. bundle install
    • b. bundle install --gemfile
    • c. bundle update
    • d. git add .
    • e. git commit -m "updates for heroku deployment"
    • f. git pust heroku master (still wont work with my case)
    • g. heroku buildpacks:set

Loop through array of values with Arrow Function

In short:

someValues.forEach((element) => {

If you care about index, then second parameter can be passed to receive the index of current element:

someValues.forEach((element, index) => {
    console.log(`Current index: ${index}`);

Refer here to know more about Array of ES6:

Should methods in a Java interface be declared with or without a public access modifier?

I disagree with the popular answer, that having public implies that there are other options and so it shouldn't be there. The fact is that now with Java 9 and beyond there ARE other options.

I think instead Java should enforce/require 'public' to be specified. Why? Because the absence of a modifier means 'package' access everywhere else, and having this as a special case is what leads to the confusion. If you simply made it a compile error with a clear message (e.g. "Package access is not allowed in an interface.") we would get rid of the apparent ambiguity that having the option to leave out 'public' introduces.

Note the current wording at:

"A method in the body of an interface may be declared public or private (§6.6). If no access modifier is given, the method is implicitly public. It is permitted, but discouraged as a matter of style, to redundantly specify the public modifier for a method declaration in an interface."

See that 'private' IS allowed now. I think that last sentence should have been removed from the JLS. It is unfortunate that the "implicitly public" behaviour was ever allowed as it will now likely remain for backward compatibilty and lead to the confusion that the absence of the access modifier means 'public' in interfaces and 'package' elsewhere.

git submodule tracking latest

Edit (2020.12.28): GitHub change default master branch to main branch since October 2020. See

Update March 2013

Git 1.8.2 added the possibility to track branches.

"git submodule" started learning a new mode to integrate with the tip of the remote branch (as opposed to integrating with the commit recorded in the superproject's gitlink).

# add submodule to track master branch
git submodule add -b master [URL to Git repo];

# update your submodule
git submodule update --remote 

If you had a submodule already present you now wish would track a branch, see "how to make an existing submodule track a branch".

Also see Vogella's tutorial on submodules for general information on submodules.


git submodule add -b . [URL to Git repo];

See git submodule man page:

A special value of . is used to indicate that the name of the branch in the submodule should be the same name as the current branch in the current repository.

See commit b928922727d6691a3bdc28160f93f25712c565f6:

submodule add: If --branch is given, record it in .gitmodules

This allows you to easily record a submodule.<name>.branch option in .gitmodules when you add a new submodule. With this patch,

$ git submodule add -b <branch> <repository> [<path>]
$ git config -f .gitmodules submodule.<path>.branch <branch>

reduces to

$ git submodule add -b <branch> <repository> [<path>]

This means that future calls to

$ git submodule update --remote ...

will get updates from the same branch that you used to initialize the submodule, which is usually what you want.

Signed-off-by: W. Trevor King [email protected]

Original answer (February 2012):

A submodule is a single commit referenced by a parent repo.
Since it is a Git repo on its own, the "history of all commits" is accessible through a git log within that submodule.

So for a parent to track automatically the latest commit of a given branch of a submodule, it would need to:

  • cd in the submodule
  • git fetch/pull to make sure it has the latest commits on the right branch
  • cd back in the parent repo
  • add and commit in order to record the new commit of the submodule.

gitslave (that you already looked at) seems to be the best fit, including for the commit operation.

It is a little annoying to make changes to the submodule due to the requirement to check out onto the correct submodule branch, make the change, commit, and then go into the superproject and commit the commit (or at least record the new location of the submodule).

Other alternatives are detailed here.

How to add google-play-services.jar project dependency so my project will run and present map

The quick start guide that keyboardsurfer references will work if you need to get your project to build properly, but it leaves you with a dummy google-play-services project in your Eclipse workspace, and it doesn't properly link Eclipse to the Google Play Services Javadocs.

Here's what I did instead:

  1. Install the Google Play Services SDK using the instructions in the Android Maps V2 Quick Start referenced above, or the instructions to Setup Google Play Services SDK, but do not follow the instructions to add Google Play Services into your project.

  2. Right click on the project in the Package Explorer, select Properties to open the properties for your project.

  3. (Only if you already followed the instructions in the quick start guide!) Remove the dependency on the google-play-services project:

    • Click on the Android category and remove the reference to the google-play-services project.

    • Click on the Java Build Path category, then the Projects tab and remove the reference to the google-play-services project.

  4. Click on the Java Build Path category, then the Libraries tab.

  5. Click Add External JARs... and select the google-play-services.jar file. This should be in [Your ADT directory]\sdk\extras\google\google_play_services\libproject\google-play-services_lib\libs.

  6. Click on the arrow next to the new google-play-services.jar entry, and select the Javadoc Location item.

  7. Click Edit... and select the folder containing the Google Play Services Javadocs. This should be in [Your ADT directory]\sdk\extras\google\google_play_services\docs\reference.

  8. Still in the Java Build Path category, click on the Order and Export tab. Check the box next to the google-play-services.jar entry.

  9. Click OK to save your project properties.

Your project should now have access to the Google Play Services library, and the Javadocs should display properly in Eclipse.

Is there a way to make Firefox ignore invalid ssl-certificates?

Create some nice new 10 year certificates and install them. The procedure is fairly easy.

Start at (1B) Generate your own CA (Certificate Authority) on this web page: Creating Certificate Authorities and self-signed SSL certificates and generate your CA Certificate and Key. Once you have these, generate your Server Certificate and Key. Create a Certificate Signing Request (CSR) and then sign the Server Key with the CA Certificate. Now install your Server Certificate and Key on the web server as usual, and import the CA Certificate into Internet Explorer's Trusted Root Certification Authority Store (used by the Flex uploader and Chrome as well) and into Firefox's Certificate Manager Authorities Store on each workstation that needs to access the server using the self-signed, CA-signed server key/certificate pair.

You now should not see any warning about using self-signed Certificates as the browsers will find the CA certificate in the Trust Store and verify the server key has been signed by this trusted certificate. Also in e-commerce applications like Magento, the Flex image uploader will now function in Firefox without the dreaded "Self-signed certificate" error message.


I rely on NDEBUG, because it's the only one whose behavior is standardized across compilers and implementations (see documentation for the standard assert macro). The negative logic is a small readability speedbump, but it's a common idiom you can quickly adapt to.

To rely on something like _DEBUG would be to rely on an implementation detail of a particular compiler and library implementation. Other compilers may or may not choose the same convention.

The third option is to define your own macro for your project, which is quite reasonable. Having your own macro gives you portability across implementations and it allows you to enable or disable your debugging code independently of the assertions. Though, in general, I advise against having different classes of debugging information that are enabled at compile time, as it causes an increase in the number of configurations you have to build (and test) for arguably small benefit.

With any of these options, if you use third party code as part of your project, you'll have to be aware of which convention it uses.

How to check if a file exists in the Documents directory in Swift?

works at Swift 5

    do {
        let documentDirectory = try FileManager.default.url(for: .documentDirectory, in: .userDomainMask, appropriateFor: nil, create: true)
        let fileUrl = documentDirectory.appendingPathComponent("userInfo").appendingPathExtension("sqlite3")
        if FileManager.default.fileExists(atPath: fileUrl.path) {
            print("FILE AVAILABLE")
        } else {
            print("FILE NOT AVAILABLE")
    } catch {

where "userInfo" - file's name, and "sqlite3" - file's extension

Angular 2 - Setting selected value on dropdown list

This works for me.

<select formControlName="preferredBankAccountId" class="form-control" value="">
    <option value="">Please select</option>    
    <option *ngFor="let item of societyAccountDtos" [value]="item.societyAccountId" >{{item.nickName}}</option>

Not sure this is valid or not, correct me if it's wrong.
Correct me if this should not be like this.

ERROR: SQLSTATE[HY000] [2002] No connection could be made because the target machine actively refused it

Check whether MySQL server is running at all. If you not run apache server(or any server you use) this could happen. After run your local server and refresh the page.

Java Convert GMT/UTC to Local time doesn't work as expected

I also recommend using Joda as mentioned before.

Solving your problem using standard Java Date objects only can be done as follows:

    // **** YOUR CODE **** BEGIN ****
    long ts = System.currentTimeMillis();
    Date localTime = new Date(ts);
    String format = "yyyy/MM/dd HH:mm:ss";
    SimpleDateFormat sdf = new SimpleDateFormat(format);

    // Convert Local Time to UTC (Works Fine)
    Date gmtTime = new Date(sdf.format(localTime));
    System.out.println("Local:" + localTime.toString() + "," + localTime.getTime() + " --> UTC time:"
            + gmtTime.toString() + "," + gmtTime.getTime());

    // **** YOUR CODE **** END ****

    // Convert UTC to Local Time
    Date fromGmt = new Date(gmtTime.getTime() + TimeZone.getDefault().getOffset(localTime.getTime()));
    System.out.println("UTC time:" + gmtTime.toString() + "," + gmtTime.getTime() + " --> Local:"
            + fromGmt.toString() + "-" + fromGmt.getTime());


Local:Tue Oct 15 12:19:40 CEST 2013,1381832380522 --> UTC time:Tue Oct 15 10:19:40 CEST 2013,1381825180000
UTC time:Tue Oct 15 10:19:40 CEST 2013,1381825180000 --> Local:Tue Oct 15 12:19:40 CEST 2013-1381832380000

Angular: Can't find Promise, Map, Set and Iterator

Angular 2 Final

- es5 support (Works perfectly with TS 2.0.0 +)

Per update es6-shim isn't supported now, if you have both typings installed together es6-shim & core-js together. Remove es6-shim typing by mentioning in tsconfig.json. You could now refer below core-js typing for es5 support inside main.ts

///<reference path="./../typings/globals/core-js/index.d.ts"/>


exclude: [
   "node_modules", //<-- this would be needed in case of VS2015

- es6 suppport

You just need to set "target" property to es6, then all will error go away. And the transpiled code will be in es6 format.

Pandas: Return Hour from Datetime Column Directly

You can try this:

sales['time_hour'] = pd.to_datetime(sales['timestamp']).dt.hour

What are the most common font-sizes for H1-H6 tags

Headings are normally bold-faced; that has been turned off for this demonstration of size correspondence. MSIE and Opera interpret these sizes the same, but note that Gecko browsers and Chrome interpret Heading 6 as 11 pixels instead of 10 pixels/font size 1, and Heading 3 as 19 pixels instead of 18 pixels/font size 4 (though it's difficult to tell the difference even in a direct comparison and impossible in use). It seems Gecko also limits text to no smaller than 10 pixels.

List of standard lengths for database fields

|   Field    | Length (Char) |           Description           |
|firstname   | 35            |                                 |
|lastname    | 35            |                                 |
|email       | 255           |                                 |
|url         | 60+           | According to server and browser |
|city        | 45            |                                 |
|address     | 90            |                                 |

Edit: Added some spacing

Should Gemfile.lock be included in .gitignore?

The real problem happens when you are working on an open-source Rails app that needs to have a configurable database adapter. I'm developing the Rails 3 branch of Fat Free CRM. My preference is postgres, but we want the default database to be mysql2.

In this case, Gemfile.lock still needs be checked in with the default set of gems, but I need to ignore changes that I have made to it on my machine. To accomplish this, I run:

git update-index --assume-unchanged Gemfile.lock

and to reverse:

git update-index --no-assume-unchanged Gemfile.lock

It is also useful to include something like the following code in your Gemfile. This loads the appropriate database adapter gem, based on your database.yml.

# Loads the database adapter gem based on config/database.yml (Default: mysql2)
# -----------------------------------------------------------------------------
db_gems = {"mysql2"     => ["mysql2", ">= 0.2.6"],
           "postgresql" => ["pg",     ">= 0.9.0"],
           "sqlite3"    => ["sqlite3"]}
adapter = if File.exists?(db_config = File.join(File.dirname(__FILE__),"config","database.yml"))
  db = YAML.load_file(db_config)
  # Fetch the first configured adapter from config/database.yml
  (db["production"] || db["development"] || db["test"])["adapter"]
gem *db_gems[adapter]
# -----------------------------------------------------------------------------

I can't say if this is an established best practice or not, but it works well for me.

Unable to preventDefault inside passive event listener

I am getting this issue when using owl carousal and scrolling the images.

So get solved just adding below CSS in your page.

.owl-carousel {
-ms-touch-action: pan-y;
touch-action: pan-y;


.owl-carousel {
-ms-touch-action: none;
touch-action: none;

iCheck check if checkbox is checked

You just need to use the callbacks, from the documentation:

$('input').on('ifChecked', function(event){
  alert(event.type + ' callback');

In PowerShell, how do I test whether or not a specific variable exists in global scope?

Test-Path can be used with a special syntax:

Test-Path variable:global:foo

This also works for environment variables ($env:foo):

Test-Path env:foo

And for non-global variables (just $foo inline):

Test-Path variable:foo

Perl: function to trim string leading and trailing whitespace

For those that are using Text::CSV I found this thread and then noticed within the CSV module that you could strip it out via switch:

$csv = Text::CSV->new({allow_whitespace => 1});

The logic is backwards in that if you want to strip then you set to 1. Go figure. Hope this helps anyone.

Setting up Gradle for api 26 (Android)

allprojects {
    repositories {
        maven {
            url ""

android {
    compileSdkVersion 26
    buildToolsVersion "26.0.1"
    defaultConfig {
        applicationId "com.keshav.retroft2arrayinsidearrayexamplekeshav"
        minSdkVersion 15
        targetSdkVersion 26
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner ""
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), ''
 compile ''
    compile ''
    compile ''

JavaScript CSS how to add and remove multiple CSS classes to an element

Try this:

function addClass(element, value) {
  if(!element.className) {
    element.className = value;
  } else {
    newClassName = element.className;
    newClassName+= " ";
    newClassName+= value;
    element.className = newClassName;

Similar logic could be used to make a removeClass function.

Git - How to use .netrc file on Windows to save user and password

You can also install Git Credential Manager for Windows to save Git passwords in Windows credentials manager instead of _netrc. This is a more secure way to store passwords.

Completely remove MariaDB or MySQL from CentOS 7 or RHEL 7


sudo systemctl stop mysqld.service && sudo yum remove -y mariadb mariadb-server && sudo rm -rf /var/lib/mysql /etc/my.cnf


sudo service mysql stop && sudo apt-get remove mariadb mariadb-server && sudo rm -rf /var/lib/mysql /etc/my.cnf

List comprehension on a nested list?

Here is how you would do this with a nested list comprehension:

[[float(y) for y in x] for x in l]

This would give you a list of lists, similar to what you started with except with floats instead of strings. If you want one flat list then you would use [float(y) for x in l for y in x].

Most efficient way to find mode in numpy array

If you want to use numpy only:

x = [-1, 2, 1, 3, 3]
vals,counts = np.unique(x, return_counts=True)


(array([-1,  1,  2,  3]), array([1, 1, 1, 2]))

And extract it:

index = np.argmax(counts)
return vals[index]

Bundle ID Suffix? What is it?

The bundle identifier is an ID for your application used by the system as a domain for which it can store settings and reference your application uniquely.

It is represented in reverse DNS notation and it is recommended that you use your company name and application name to create it.

An example bundle ID for an App called The Best App by a company called Awesome Apps would look like:


In this case the suffix is thebestapp.

Random Number Between 2 Double Numbers

What if one of the values is negative? Wouldn't a better idea be:

double NextDouble(double min, double max)
       if (min >= max)
            throw new ArgumentOutOfRangeException();    
       return random.NextDouble() * (Math.Abs(max-min)) + min;

Div Height in Percentage

It doesn't take the 50% of the whole page is because the "whole page" is only how tall your contents are. Change the enclosing html and body to 100% height and it will work.

html, body{
    height: 100%;
    height: 50%;

enter image description here

^ Your document is only 20px high. 50% of 20px is 10px, and it is not what you expected.

enter image description here

^ Now if you change the height of the document to the height of the whole page (150px), 50% of 150px is 75px, then it will work.

WordPress - Check if user is logged in

This problem is from the lazy update data request of Chrome. At the first time you go to homepage. Chrome request with empty data. Then you go to the login page and logged in. When you back home page Chrome lazy to update the cookie data request because this domain is the same with the first time you access. Solution: Add parameter for home url. That helps Chrome realizes that this request need to update cookie to call to the server.

add at dashboard page

$track = '?track='.uniqid();
<a href="<?= get_home_url(). $track ?>"> <img src="/img/logo.svg"></a>

import android packages cannot be resolved

try this in eclipse: Window - Preferences - Android - SDK Location and setup SDK path

Should IBOutlets be strong or weak under ARC?

It looks like something has changed over the years and now Apple recommends to use strong in general. The evidence on their WWDC session is in session 407 - Implementing UI Designs in Interface Builder and starts at 32:30. My note from what he says is (almost, if not exactly, quoting him):

  • outlet connections in general should be strong especially if we connect a subview or constraint that is not always retained by the view hierarchy

  • weak outlet connection might be needed when creating custom views that has some reference to something back up in the view hierarchy and in general it is not recommended

In other wards it should be always strong now as long as some of our custom view doesn't create a retain cycle with some of the view up in the view hierarchy


Some may ask the question. Does keeping it with a strong reference doesn't create a retain cycle as the root view controller and the owning view keeps the reference to it? Or why that changed happened? I think the answer is earlier in this talk when they describe how the nibs are created from the xib. There is a separate nib created for a VC and for the view. I think this might be the reason why they change the recommendations. Still it would be nice to get a deeper explanation from Apple.

Returning the product of a list

I remember some long discussions on comp.lang.python (sorry, too lazy to produce pointers now) which concluded that your original product() definition is the most Pythonic.

Note that the proposal is not to write a for loop every time you want to do it, but to write a function once (per type of reduction) and call it as needed! Calling reduction functions is very Pythonic - it works sweetly with generator expressions, and since the sucessful introduction of sum(), Python keeps growing more and more builtin reduction functions - any() and all() are the latest additions...

This conclusion is kinda official - reduce() was removed from builtins in Python 3.0, saying:

"Use functools.reduce() if you really need it; however, 99 percent of the time an explicit for loop is more readable."

See also The fate of reduce() in Python 3000 for a supporting quote from Guido (and some less supporting comments by Lispers that read that blog).

P.S. if by chance you need product() for combinatorics, see math.factorial() (new 2.6).

Resource interpreted as Document but transferred with MIME type application/json warning in Chrome Developer Tools

you can simply use JSON.stringify(options) convert JSON object to string before submit, then warning dismiss and works fine

How do I correctly detect orientation change using Phonegap on iOS?

if (window.matchMedia("(orientation: portrait)").matches) {
   // you're in PORTRAIT mode

if (window.matchMedia("(orientation: landscape)").matches) {
  // you're in LANDSCAPE mode

HTML <sup /> tag affecting line height, how to make it consistent?

The reason why the <sup> tag is affecting the spacing between two lines has to do with a number of factors. The factors are: line height, size of the superscript in relation to the regular font, the line height of the superscript and last but not least what is the bottom of the superscript aligning with... If you set... the line height of regular text to be in a "tunnel band" (that's what I call it) of 135% then regular text (the 100%) gets white padded by 35% of more white. For a paragraph this looks like this:

            line-height: 135%;

If you then do not white pad the superscript...(i.e. keep its line height to 0) the superscript only has the width of its own text... if you then ask the superscript to be a percentage of the regular font (for example 70%) and you align it with the middle of the regular text (text-middle), you can eliminate the problem and get a superscript that looks like a superscript. Here it is:

    font-size: 70%;
    vertical-align: text-middle;
    line-height: 0;

"com.jcraft.jsch.JSchException: Auth fail" with working passwords

I have also face the Auth Fail issue, the problem with my code is that I have"");

It changed it to".");

Then it works.

How do I check for vowels in JavaScript?

I kind of like this method which I think covers all the bases:

const matches = str.match(/aeiou/gi];
return matches ? matches.length : 0;

How do I hide javascript code in a webpage?

I'm not sure anyone else actually addressed your question directly which is code being viewed from the browser's View Source command.

As other have said, there is no way to protect javascript intended to run in a browser from a determined viewer. If the browser can run it, then any determined person can view/run it also.

But, if you put your javascript in an external javascript file that is included with:

<script type="text/javascript" src=""></script>

tags, then the javascript code won't be immediately visible with the View Source command - only the script tag itself will be visible that way. That doesn't mean that someone can't just load that external javascript file to see it, but you did ask how to keep it out of the browser's View Source command and this will do it.

If you wanted to really make it more work to view the source, you would do all of the following:

  1. Put it in an external .js file.
  2. Obfuscate the file so that most native variable names are replaced with short versions, so that all unneeded whitespace is removed, so it can't be read without further processing, etc...
  3. Dynamically include the .js file by programmatically adding script tags (like Google Analytics does). This will make it even more difficult to get to the source code from the View Source command as there will be no easy link to click on there.
  4. Put as much interesting logic that you want to protect on the server that you retrieve via ajax calls rather than do local processing.

With all that said, I think you should focus on performance, reliability and making your app great. If you absolutely have to protect some algorithm, put it on the server, but other than that, compete on being the best at you do, not by having secrets. That's ultimately how success works on the web anyway.

What are the retransmission rules for TCP?

What exactly are the rules for requesting retransmission of lost data?

The receiver does not request the retransmission. The sender waits for an ACK for the byte-range sent to the client and when not received, resends the packets, after a particular interval. This is ARQ (Automatic Repeat reQuest). There are several ways in which this is implemented.

Stop-and-wait ARQ
Go-Back-N ARQ
Selective Repeat ARQ

are detailed in the RFC 3366.

At what time frequency are the retransmission requests performed?

The retransmissions-times and the number of attempts isn't enforced by the standard. It is implemented differently by different operating systems, but the methodology is fixed. (One of the ways to fingerprint OSs perhaps?)

The timeouts are measured in terms of the RTT (Round Trip Time) times. But this isn't needed very often due to Fast-retransmit which kicks in when 3 Duplicate ACKs are received.

Is there an upper bound on the number?

Yes there is. After a certain number of retries, the host is considered to be "down" and the sender gives up and tears down the TCP connection.

Is there functionality for the client to indicate to the server to forget about the whole TCP segment for which part went missing when the IP packet went missing?

The whole point is reliable communication. If you wanted the client to forget about some part, you wouldn't be using TCP in the first place. (UDP perhaps?)

How to Convert Datetime to Date in dd/MM/yyyy format

Give a different alias

SELECT  Convert(varchar,A.InsertDate,103) as converted_Tran_Date from table as A
order by A.InsertDate 

Copy file remotely with PowerShell

None of the above answers worked for me. I kept getting this error:

Copy-Item : Access is denied
+ CategoryInfo          : PermissionDenied: (\\\Shared\test.txt:String) [Copy-Item], UnauthorizedAccessException>   
+ FullyQualifiedErrorId : ItemExistsUnauthorizedAccessError,Microsoft.PowerShell.Commands.CopyItemCommand

So this did it for me:

netsh advfirewall firewall set rule group="File and Printer Sharing" new enable=yes

Then from my host my machine in the Run box I just did this:

\\{IP address of nanoserver}\C$

Have Excel formulas that return 0, make the result blank

The question may be why would you want it to act different from how it does right now? Apart from writing your own enveloping function or an alternative function in VBA (which will probably cause calculation speed reduction in large files) there might not be a single solution to your different problems.

Any follow up formula's would most probably fail over a blank thus cause an error that you would capture with IFERROR() or prevent by IF(sourcecell<>"";...), if you would use the latter then testing for a zero is just the same amount of work and clutter. Checking for blank cells becomes checking for 0 valued cells. (if this doenst work for you please explain more specific what the problem is).

For esthetic purposes the custom formatting solution would be just fine.

For charts there might be an issue, which would be solved by applying it in the original formula indeed.

Avoid "current URL string parser is deprecated" warning by setting useNewUrlParser to true

The following works for me

const mongoose = require('mongoose');

mongoose.connect("mongodb://localhost/playground", { useNewUrlParser: true,useUnifiedTopology: true })
.then(res => console.log('Connected to db'));

The mongoose version is 5.8.10.

Docker error response from daemon: "Conflict ... already in use by container"

Instead of command: docker run

You should use:

docker start **CONTAINER ID**

because the container is already exist

More info

How to JUnit test that two List<E> contain the same elements in the same order?

org.junit.Assert.assertEquals() and org.junit.Assert.assertArrayEquals() do the job.

To avoid next questions: If you want to ignore the order put all elements to set and then compare: Assert.assertEquals(new HashSet<String>(one), new HashSet<String>(two))

If however you just want to ignore duplicates but preserve the order wrap you list with LinkedHashSet.

Yet another tip. The trick Assert.assertEquals(new HashSet<String>(one), new HashSet<String>(two)) works fine until the comparison fails. In this case it shows you error message with to string representations of your sets that can be confusing because the order in set is almost not predictable (at least for complex objects). So, the trick I found is to wrap the collection with sorted set instead of HashSet. You can use TreeSet with custom comparator.

How may I reference the script tag that loaded the currently-executing script?

Consider this algorithm. When your script loads (if there are multiple identical scripts), look through document.scripts, find the first script with the correct "src" attribute, and save it and mark it as 'visited' with a data-attribute or unique className.

When the next script loads, scan through document.scripts again, passing over any script already marked as visited. Take the first unvisited instance of that script.

This assumes that identical scripts will likely execute in the order in which they are loaded, from head to body, from top to bottom, from synchronous to asynchronous.

(function () {
  var scripts = document.scripts;

  // Scan for this data-* attribute
  var dataAttr = 'data-your-attribute-here';

  var i = 0;
  var script;
  while (i < scripts.length) {
    script = scripts[i];
    if (/your_script_here\.js/i.test(script.src)
        && !script.hasAttribute(dataAttr)) {

        // A good match will break the loop before
        // script is set to null.

    // If we exit the loop through a while condition failure,
    // a check for null will reveal there are no matches.
    script = null;

   * This specific your_script_here.js script tag.
   * @type {Element|Node}
  var yourScriptVariable = null;

  // Mark the script an pass it on.
  if (script) {
    script.setAttribute(dataAttr, '');
    yourScriptVariable = script;

This will scan through all the script for the first matching script that isn't marked with the special attribute.

Then mark that node, if found, with a data-attribute so subsequent scans won't choose it. This is similar to graph traversal BFS and DFS algorithms where nodes may be marked as 'visited' to prevent revisitng.

Apache Name Virtual Host with SSL

It sounds like Apache is warning you that you have multiple <VirtualHost> sections with the same IP address and port... as far as getting it to work without warnings, I think you would need to use something like Server Name Indication (SNI), a way of identifying the hostname requested as part of the SSL handshake. Basically it lets you do name-based virtual hosting over SSL, but I'm not sure how well it's supported by browsers. Other than something like SNI, you're basically limited to one SSL-enabled domain name for each IP address you expose to the public internet.

Of course, if you are able to access the websites properly, you'll probably be fine ignoring the warnings. These particular ones aren't very serious - they're mainly an indication of what to look at if you are experiencing problems

Creating the checkbox dynamically using JavaScript?

   /* worked for me  */
     <div id="divid"> </div>
     <script type="text/javascript">
         var hold = document.getElementById("divid");
         var checkbox = document.createElement('input');
         checkbox.type = "checkbox"; = "chkbox1"; = "cbid";
         var label = document.createElement('label');
         var tn = document.createTextNode("Not A RoBot");

Is there a method for String conversion to Title Case?

This should work:

String str="i like pancakes";
String arr[]=str.split(" ");
String strNew="";
for(String str1:arr)
    Character oldchar=str1.charAt(0);
    Character newchar=Character.toUpperCase(str1.charAt(0));
    strNew=strNew+str1.replace(oldchar,newchar)+" ";    

Difference between return and exit in Bash functions

return will cause the current function to go out of scope, while exit will cause the script to end at the point where it is called. Here is a sample program to help explain this:


    echo "this is retfunc()"
    return 1

    echo "this is exitfunc()"
    exit 1

echo "We are still here"
echo "We will never see this"


$ ./
this is retfunc()
We are still here
this is exitfunc()

Can't push to remote branch, cannot be resolved to branch

Based on my own testing and the OP's comments, I think at some point they goofed on the casing of the branch name.

First, I believe the OP is on a case insensitive operating system like OS X or Windows. Then they did something like this...

$ git checkout -b SQLMigration/ReportFixes
Switched to a new branch 'SQLMigration/ReportFixes'

$ git push origin SqlMigration/ReportFixes
fatal: SqlMigration/ReportFixes cannot be resolved to branch.

Note the casing difference. Also note the error is very different from if you just typo the name.

$ git push origin SQLMigration/ReportFixme
error: src refspec SQLMigration/ReportFixme does not match any.
error: failed to push some refs to '[email protected]:schwern/testing123.git'

Because Github uses the filesystem to store branch names, it tries to open .git/refs/heads/SqlMigration/ReportFixes. Because the filesystem is case insensitive it successfully opens .git/refs/heads/SqlMigration/ReportFixes but gets confused when it tries to compare the branch names case-sensitively and they don't match.

How they got into a state where the local branch is SQLMigration/ReportFixes and the remote branch is SqlMigration/ReportFixes I'm not sure. I don't believe Github messed with the remote branch name. Simplest explanation is someone else with push access changed the remote branch name. Otherwise, at some point they did something which managed to create the remote with the typo. If they check their shell history, perhaps with history | grep -i sqlmigration/reportfixes they might be able to find a command where they mistyped the casing.

Stack array using pop() and push()

Better solution for your Stack implementation

import java.util.List;
import java.util.ArrayList;
public class IntegerStack 


    private List<Integer> stack;

    public IntegerStack(int SIZE) 
        stack = new ArrayList<Integer>(SIZE);

    public void push(int i) 


     public int pop() 
           int i= stack.get(0);
           return i;
        } else{
           return -1;// Or any invalid value

     public int peek()
           return stack.get(0);
        } else{
           return -1;// Or any invalid value

     public boolean isEmpty() 


If you have to use Array... Here are problems in your code and possible solutions

import java.util.Arrays;
public class IntegerStack 

    private int stack [];
    private int top; 

    public IntegerStack(int SIZE) 
    stack = new int [SIZE];
    top = -1; // top should be 0. If you keep it as -1, problems will arise when SIZE is passed as 0. 
    // In your push method -1==0 will be false and your code will try to add the invalid element to Stack .. 
     /**Solution top=0; */

public void push(int i) 
    if (top == stack.length)

       stack[top]= i;


public int pop() 
    top --; // here you are reducing the top before giving the Object back 
      int value = stack[top];
       top --;
     return value; 
    } else{
      return -1;// OR invalid value
    return stack[top];

public int peek()
    return stack[top]; // Problem when stack is empty or size is 0
         return stack[top];
         return -1;// Or any invalid value


public boolean isEmpty() 
    if ( top == -1); // problem... we changed top to 0 above so here it need to check if its 0 and there should be no semicolon after the if statement
   /* Solution if(top==0) */
        return true;

private void extendStack()

    int [] copy = Arrays.copyOf(stack, stack.length); // The second parameter in Arrays.copyOf has no changes, so there will be no change in array length.
    stack=Arrays.copyOf(stack, stack.length+1); 


Java: int[] array vs int array[]

Both are the same. I usually use int[] array = new int[10];, because of better (contiguous) readability of the type int[].

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

Try this

cd repo1

This will remove all the directories except the ones mentioned, preserving history only for these directories

git filter-branch --index-filter 'git rm --ignore-unmatch --cached -qr -- . && git reset -q $GIT_COMMIT -- dir1/ dir2/ dir3/ ' --prune-empty -- --all

Now you can add your new repo in your git remote and push it to that

git remote remove origin <old-repo>
git remote add origin <new-repo>
git push origin <current-branch>

add -f to overwrite

SQL RANK() over PARTITION on joined tables

As the rank doesn't depend at all from the contacts


   A     |    1     |    15  |   3
   A     |    2     |    32  |   1
   A     |    3     |    29  |   2
   C     |    7     |    61  |   1
   C     |    9     |    30  |   2

Thus :


How to correct indentation in IntelliJ

You can also try out ctrl + alt + I even though you can also use l as well.

jquery $(this).id return Undefined

Hiya demo

this is a reference to the DOM element, so you can wrap it directly.

attr api:

The .attr() method gets the attribute value for only the first element in the matched set.

have a nice one, cheers!


$(document).ready(function () {
    $(".inputs").click(function () {

        alert(" or " + $(this).attr("id"));



Telegram Bot - how to get a group chat id?

You can retrieve the group ID the same way. It appears in the message body as and it's usually a negative number, where normal chats are positive.

Group IDs and Chat IDs can only be retrieved from a received message, there are no calls available to retrieve active groups etc. You have to remember the group ID when you receive the message and store it in cache or something similar.

Angular ui-grid dynamically calculate height of the grid


The HTML was requested so I've pasted it below.

<div ui-grid="gridOptions" class="my-grid"></div>


We were able to adequately solve this problem by using responsive CSS (@media) that sets the height and width based on screen real estate. Something like (and clearly you can add more based on your needs):

@media (min-width: 1024px) {
  .my-grid {
    width: 772px;

@media (min-width: 1280px) {
  .my-grid {
    width: 972px;

@media (min-height: 768px) {
  .my-grid {
    height: 480px;

@media (min-height: 900px) {
  .my-grid {
    height: 615px;

The best part about this solution is that we need no resize event handling to monitor for grid size changes. It just works.

Removing underline with href attribute

Add a style with the attribute text-decoration:none;:

There are a number of different ways of doing this.

Inline style:

<a href="xxx.html" style="text-decoration:none;">goto this link</a>

Inline stylesheet:

<style type="text/css">
   a {
<a href="xxx.html">goto this link</a>

External stylesheet:

<link rel="Stylesheet" href="stylesheet.css" />
<a href="xxx.html">goto this link</a>


a {

How to add and get Header values in WebApi

Another way using a the TryGetValues method.

public string Postsam([FromBody]object jsonData)
    IEnumerable<string> headerValues;

    if (Request.Headers.TryGetValues("Custom", out headerValues))
        string token = headerValues.First();

How to install iPhone application in iPhone Simulator

This thread discusses how to install the binary on the simulator. I've done it and it works:

From the thread:

Look inside your ~/Library/Application Support/iPhone Simulator/User/Applications/ directory and see what happens inside this directory when you install and run apps using XCode, and also when you delete apps using the Simulator.

You can run the Simulator by itself (without starting XCode).

If you start the Simulator, delete an app, quit the Simulator, put back copies of the files that were deleted from the support directory, and restart the Simulator, the app will reappear in the Simulator. Email those files with instructions about how to copy them into the appropriate support directory.

How can I scroll up more (increase the scroll buffer) in iTerm2?

There is an option “unlimited scrollback buffer” which you can find under Preferences > Profiles > Terminal or you can just pump up number of lines that you want to have in history in the same place.

How to get HTTP Response Code using Selenium WebDriver

Not sure this is what you're looking for, but I had a bit different goal is to check if remote image exists and I will not have 403 error, so you could use something like below:

public static boolean linkExists(String URLName){
    try {
        HttpURLConnection con = (HttpURLConnection) new URL(URLName).openConnection();
        return (con.getResponseCode() == HttpURLConnection.HTTP_OK);
    catch (Exception e) {
        return false;

How does the getView() method work when creating your own custom adapter?

What is exactly the function of the LayoutInflater?

When you design using XML, all your UI elements are just tags and parameters. Before you can use these UI elements, (eg a TextView or LinearLayout), you need to create the actual objects corresponding to these xml elements. That is what the inflater is for. The inflater, uses these tags and their corresponding parameters to create the actual objects and set all the parameters. After this you can get a reference to the UI element using findViewById().

Why do all the articles that I've read check if convertview is null or not first? What does it mean when it is null and what does it mean when it isn't?

This is an interesting one. You see, getView() is called everytime an item in the list is drawn. Now, before the item can be drawn, it has to be created. Now convertView basically is the last used view to draw an item. In getView() you inflate the xml first and then use findByViewID() to get the various UI elements of the listitem. When we check for (convertView == null) what we do is check that if a view is null(for the first item) then create it, else, if it already exists, reuse it, no need to go through the inflate process again. Makes it a lot more efficient.

You must also have come across a concept of ViewHolder in getView(). This makes the list more efficient. What we do is create a viewholder and store the reference to all the UI elements that we got after inflating. This way, we can avoid calling the numerous findByViewId() and save on a lot of time. This ViewHolder is created in the (convertView == null) condition and is stored in the convertView using setTag(). In the else loop we just obtain it back using getView() and reuse it.

What is the parent parameter that this method accepts?

The parent is a ViewGroup to which your view created by getView() is finally attached. Now in your case this would be the ListView.

Hope this helps :)

Entity Framework code first unique column

In Entity Framework 6.1+ you can use this attribute on your model:


You can find it in this namespace:

using System.ComponentModel.DataAnnotations.Schema;

If your model field is a string, make sure it is not set to nvarchar(MAX) in SQL Server or you will see this error with Entity Framework Code First:

Column 'x' in table 'dbo.y' is of a type that is invalid for use as a key column in an index.

The reason is because of this:

SQL Server retains the 900-byte limit for the maximum total size of all index key columns."

(from: )

You can solve this by setting a maximum string length on your model:


Your model will look like this now in EF CF 6.1+:

public class User
   public int UserId{get;set;}
   public string UserName{get;set;}


if you use Fluent:

  public class UserMap : EntityTypeConfiguration<User>
    public UserMap()
      // ....
      Property(x => x.Name).IsRequired().HasMaxLength(450).HasColumnAnnotation("Index", new IndexAnnotation(new[] { new IndexAttribute("Index") { IsUnique = true } }));

and use in your modelBuilder:

protected override void OnModelCreating(DbModelBuilder modelBuilder)
  // ...
  modelBuilder.Configurations.Add(new UserMap());
  // ...

Update 2

for EntityFrameworkCore see also this topic:

Update 3

for EF6.2 see:

Update 4

ASP.NET Core Mvc 2.2 with EF Core:

public Guid Unique { get; set; }

How do I print the type or class of a variable in Swift?

In the latest XCode 6.3 with Swift 1.2, this is the only way I found:

if view.classForCoder.description() == "UISegment" {

SVG rounded corner

You are using a path element, why don't you just give the path a curve? See here for how to make curves using path elements:

split string in two on given index and return both parts

Try this

function split_at_index(value, index)
 return value.substring(0, index) + "," + value.substring(index);

console.log(split_at_index('3123124', 2));

how to calculate percentage in python

def percentage_match(mainvalue,comparevalue):
    if mainvalue >= comparevalue:
        matched_less = mainvalue - comparevalue
        no_percentage_matched = 100 - matched_less*100.0/mainvalue
        no_percentage_matched = str(no_percentage_matched) + ' %'
        return no_percentage_matched 
        print('please checkout your value')

print percentage_match(100,10)
Ans = 10.0 %

Use string in switch case in java

Here is a possible pre-1.7 way, which I can't recommend:

public class PoorSwitch
    final static public int poorHash (String s) {
        long l = 0L;
        for (char c: s.toCharArray ()) {
            l = 97*l + c;
        return (int) l;

    public static void main (String args[])
        String param = "foo";
        if (args.length == 1)
            param = args[0];
        // uncomment these lines, to evaluate your hash
        // test ("foo");
        // test ("bar");
        switch (poorHash (param)) {
            // this doesn't work, since you need a literal constant
            // so we have to evaluate our hash beforehand:
            // case poorHash ("foo"): {
            case 970596: {
                System.out.println ("Foo!");
            // case poorHash ("bar"): {
            case 931605: {
                System.out.println ("Bar!");
            default: {
                System.out.println ("unknown\t" + param);

    public static void test (String s)
        System.out.println ("Hash:\t " + s + " =\t" + poorHash (s));

Maybe you could work with such a trick in a generated code. Else I can't recommend it. Not so much that the possibility of a hash collision makes me worry, but if something is mixed up (cut and paste), it is hard to find the error. 931605 is not a good documentation.

Take it just as proof of concept, as curiosity.

How to add constraints programmatically using Swift

    var xCenterConstraint : NSLayoutConstraint!
    var yCenterConstraint: NSLayoutConstraint!

 xCenterConstraint = NSLayoutConstraint(item: self.view, attribute: .CenterX, relatedBy: .Equal, toItem: (Your view NAme), attribute: .CenterX, multiplier: 1, constant: 0)

 yCenterConstraint = NSLayoutConstraint(item: self.view, attribute: .CenterY, relatedBy: .Equal, toItem: (Your view Name), attribute: .CenterY, multiplier: 1, constant: 0)

Copy all values in a column to a new column in a pandas dataframe

Following up on these solutions, here is some helpful code illustrating :

# Copying columns in pandas without slice warning
import numpy as np
df = pd.DataFrame(np.random.randn(10, 3), columns=list('ABC'))

# copies column B into new column D
df.loc[:,'D'] = df['B']
print df

# creates new column 'E' with values -99
# But copy command replaces those where 'B'>0 while others become NaN (not copied)
df['E'] = -99
print df
df['E'] = df[df['B']>0]['B'].copy()
print df

# creates new column 'F' with values -99
# Copy command only overwrites values which meet criteria 'B'>0
df.loc[df['B']>0,'F'] = df[df['B']>0]['B'].copy()
print df

How to trigger event in JavaScript?

The accepted answer didn’t work for me, none of the createEvent ones did.

What worked for me in the end was:

    new MouseEvent('click', {
        bubbles: true,
        cancelable: true,
        view: window,

Here’s a snippet:

const clickBtn = document.querySelector('.clickme');_x000D_
const viaBtn = document.querySelector('.viame');_x000D_
viaBtn.addEventListener('click', function(event) {_x000D_
        new MouseEvent('click', {_x000D_
            bubbles: true,_x000D_
            cancelable: true,_x000D_
            view: window,_x000D_
clickBtn.addEventListener('click', function(event) {_x000D_
    console.warn(`I was accessed via the other button! A ${event.type} occurred!`);_x000D_
<button class="clickme">Click me</button>_x000D_
<button class="viame">Via me</button>

From reading:

Difference between ref and out parameters in .NET

They are subtly different.

An out parameter does not need to be initialized by the callee before being passed to the method. Therefore, any method with an out parameter

  • Cannot read the parameter before assigning a value to it
  • Must assign a value to it before returning

This is used for a method which needs to overwrite its argument regardless of its previous value.

A ref parameter must be initialized by the callee before passing it to the method. Therefore, any method with a ref parameter

  • Can inspect the value before assigning it
  • Can return the original value, untouched

This is used for a method which must (e.g.) inspect its value and validate it or normalize it.

Android WebView not loading URL

maybe SSL

    public void onReceivedSslError(WebView view, SslErrorHandler handler, SslError error) {
        // ignore ssl error
        if (handler != null){
        } else {
            super.onReceivedSslError(view, null, error);

Reading CSV file and storing values into an array

I have a library that is doing exactly you need.

Some time ago I had wrote simple and fast enough library for work with CSV files. You can find it by the following link:

It works with CSV like with 2 dimensions array. Exactly like you need.

As example, in case of you need all of values of 3rd row only you need is to write:

Csv csv = new Csv();


var allValuesOf3rdRow = csv.Rows[2];

or to read 2nd cell of

var value = csv.Rows[2][1];

Print multiple arguments in Python

There are many ways to do this. To fix your current code using %-formatting, you need to pass in a tuple:

  1. Pass it as a tuple:

    print("Total score for %s is %s" % (name, score))

A tuple with a single element looks like ('this',).

Here are some other common ways of doing it:

  1. Pass it as a dictionary:

    print("Total score for %(n)s is %(s)s" % {'n': name, 's': score})

There's also new-style string formatting, which might be a little easier to read:

  1. Use new-style string formatting:

    print("Total score for {} is {}".format(name, score))
  2. Use new-style string formatting with numbers (useful for reordering or printing the same one multiple times):

    print("Total score for {0} is {1}".format(name, score))
  3. Use new-style string formatting with explicit names:

    print("Total score for {n} is {s}".format(n=name, s=score))
  4. Concatenate strings:

    print("Total score for " + str(name) + " is " + str(score))

The clearest two, in my opinion:

  1. Just pass the values as parameters:

    print("Total score for", name, "is", score)

    If you don't want spaces to be inserted automatically by print in the above example, change the sep parameter:

    print("Total score for ", name, " is ", score, sep='')

    If you're using Python 2, won't be able to use the last two because print isn't a function in Python 2. You can, however, import this behavior from __future__:

    from __future__ import print_function
  2. Use the new f-string formatting in Python 3.6:

    print(f'Total score for {name} is {score}')

SHA-256 or MD5 for file integrity

It is technically approved that MD5 is faster than SHA256 so in just verifying file integrity it will be sufficient and better for performance.

You are able to checkout the following resources:

Java Array, Finding Duplicates

Initialize k = j+1. You won't compare elements to themselves and you'll also not duplicate comparisons. For example, j = 0, k = 1 and k = 0, j = 1 compare the same set of elements. This would remove the k = 0, j = 1 comparison.

Position absolute but relative to parent

#father {
   position: relative;

#son1 {
   position: absolute;
   top: 0;

#son2 {
   position: absolute;
   bottom: 0;

This works because position: absolute means something like "use top, right, bottom, left to position yourself in relation to the nearest ancestor who has position: absolute or position: relative."

So we make #father have position: relative, and the children have position: absolute, then use top and bottom to position the children.

Angular 2 / 4 / 5 not working in IE11

EDIT 2018/05/15: This can be achieved with a meta tag; please add that tag to your index.html and disregard this post.

This is not a complete answer to the question (for the technical answer please refer to @Zze's answer above), but there's an important step that needs to be added:


Even with the appropriate polyfills in place, there are still issues with running Angular 2+ apps using the polyfills on IE11. If you are running the site off an intranet host (ie. if you are testing it at http://localhost or another mapped local domain name), you must go into Compatibility View settings and uncheck "Display intranet sites in Compatibility View", since IE11's Compatibility View breaks a couple of the conventions included in the ES5 polyfills for Angular.

enter image description here

Why would Oracle.ManagedDataAccess not work when Oracle.DataAccess does?

To avoid all the Oracle mess of not knowing where it is looking for the TNSNAMES.ORA (I have the added confusion of multiple Oracle versions and 32/64 bit), you can copy the setting from your existing TNSNAMES.ORA to your own config file and use that for your connection.
Say you're happy with the 'DSDSDS' reference in TNSNAMES.ORA which maps to something like:


You can take the text after the first '=' and use that wherever you are using 'DSDSDS' and it won't need to find TNSNAMES.ORA to know how to connect.
Now your connection string would look like this:
string connectionString = "Data Source=(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)(Host=DSDSDSHost)(Port=4521)))(CONNECT_DATA=(SERVICE_NAME=DSDSDSService)));User Id=UNUNUN;Password=PWPWPW;";

Where does Android emulator store SQLite database?

according to Android docs, Monitor was deprecated in Android Studio 3.1 and removed from Android Studio 3.2. To access files, there is a tab in android studio called "Device File Explorer" bottom-right side of developing window which you can access your emulator file system. Just follow


good luck.

Android device File explorer

Targeting only Firefox with CSS

CSS support has binding to javascript, as a side note.

if (CSS.supports("( -moz-user-select:unset )")) {_x000D_

Wrap long lines in Python

I'd probably split the long statement up into multiple shorter statements so that the program logic is separated from the definition of the long string:

>>> def fun():
...     format_string = '{0} Here is a really long ' \
...                     'sentence with {1}'
...     print format_string.format(3, 5)

If the string is only just too long and you choose a short variable name then by doing this you might even avoid having to split the string:

>>> def fun():
...     s = '{0} Here is a really long sentence with {1}'
...     print s.format(3, 5)

How to call a method daily, at specific time, in C#?

Try to use Windows Task Scheduler. Create an exe which is not prompting for any user inputs.

What are the proper permissions for an upload folder with PHP/Apache?

Based on the answer from @Ryan Ahearn, following is what I did on Ubuntu 16.04 to create a user front that only has permission for nginx's web dir /var/www/html.


* pre-steps:
    * basic prepare of server,
    * create user 'dev'
        which will be the owner of "/var/www/html",
    * install nginx,
* create user 'front'
    sudo useradd -d /home/front -s /bin/bash front
    sudo passwd front

    # create home folder, if not exists yet,
    sudo mkdir /home/front
    # set owner of new home folder,
    sudo chown -R front:front /home/front

    # switch to user,
    su - front

    # copy .bashrc, if not exists yet,
    cp /etc/skel/.bashrc ~front/
    cp /etc/skel/.profile ~front/

    # enable color,
    vi ~front/.bashrc
    # uncomment the line start with "force_color_prompt",

    # exit user
* add to group 'dev',
    sudo usermod -a -G dev front
* change owner of web dir,
    sudo chown -R dev:dev /var/www
* change permission of web dir,
    chmod 775 $(find /var/www/html -type d)
    chmod 664 $(find /var/www/html -type f)
* re-login as 'front'
    to make group take effect,
* test
* ok

Git update submodules recursively

As it may happens that the default branch of your submodules are not master (which happens a lot in my case), this is how I automate the full Git submodules upgrades:

git submodule init
git submodule update
git submodule foreach 'git fetch origin; git checkout $(git rev-parse --abbrev-ref HEAD); git reset --hard origin/$(git rev-parse --abbrev-ref HEAD); git submodule update --recursive; git clean -dfx'

How is a CSS "display: table-column" supposed to work?

The "table-column" display type means it acts like the <col> tag in HTML - i.e. an invisible element whose width* governs the width of the corresponding physical column of the enclosing table.

See the W3C standard for more information about the CSS table model.

* And a few other properties like borders, backgrounds.

Push method in React Hooks (useState)?

I tried the above methods for pushing an object into an array of objects in useState but had the following error when using TypeScript:

Type 'TxBacklog[] | undefined' must have a 'Symbol.iterator' method that returns an iterator.ts(2488)

The setup for the tsconfig.json was apparently right:

   "compilerOptions": {
   "target": "es6",
   "lib": [

This workaround solved the problem (my sample code):


   interface TxBacklog {
      status: string,
      txHash: string,

State variable:

    const [txBacklog, setTxBacklog] = React.useState<TxBacklog[]>();

Push new object into array:

    // Define new object to be added
    const newTx = {
       txHash: '0x368eb7269eb88ba86..',
       status: 'pending'
    // Push new object into array
       ? setTxBacklog(prevState => [ ...prevState!, newTx ])
       : setTxBacklog([newTx]);

Angular-Material DateTime Picker Component?

Unfortunately, the answer to your question of whether there is official Material support for selecting the time is "No", but it's currently an open issue on the official Material2 GitHub repo:

Hopefully this changes soon, in the mean time, you'll have to fight with the 3rd-party ones you've already discovered. There are a few people in that GitHub issue that provide their self-made workarounds that you can try.

Could not find in circle ci

My problem was that I forgot that I added a proxy in in C:\Users\(current user)\.gradle like:


How to loop through all the files in a directory in c # .net?

You can have a look at this page showing Deep Folder Copy, it uses recursive means to iterate throught the files and has some really nice tips, like filtering techniques etc.

Raise warning in Python without interrupting program

import warnings

See the python documentation: here

Convert UTF-8 to base64 string

It's a little difficult to tell what you're trying to achieve, but assuming you're trying to get a Base64 string that when decoded is abcdef==, the following should work:

byte[] bytes = Encoding.UTF8.GetBytes("abcdef==");
string base64 = Convert.ToBase64String(bytes);

This will output: YWJjZGVmPT0= which is abcdef== encoded in Base64.


To decode a Base64 string, simply use Convert.FromBase64String(). E.g.

string base64 = "YWJjZGVmPT0=";
byte[] bytes = Convert.FromBase64String(base64);

At this point, bytes will be a byte[] (not a string). If we know that the byte array represents a string in UTF8, then it can be converted back to the string form using:

string str = Encoding.UTF8.GetString(bytes);

This will output the original input string, abcdef== in this case.

ImageView rounded corners

Use this Custom ImageView in Xml

public class RoundedCornerImageView extends ImageView {

    public RoundedCornerImageView(Context ctx, AttributeSet attrs) {
        super(ctx, attrs);

    protected void onDraw(Canvas canvas) {
        Drawable drawable = getDrawable();
        if (drawable == null) {

        if (getWidth() == 0 || getHeight() == 0) {
        Bitmap b = ((BitmapDrawable) drawable).getBitmap();
        Bitmap bitmap = b.copy(Bitmap.Config.ARGB_8888, true);
        int w = getWidth(), h = getHeight();
        Bitmap roundBitmap = getRoundedCroppedBitmap(bitmap, w);
        canvas.drawBitmap(roundBitmap, 0, 0, null);

    public static Bitmap getRoundedCroppedBitmap(Bitmap bitmap, int radius) {
        Bitmap finalBitmap;
        if (bitmap.getWidth() != radius || bitmap.getHeight() != radius)
            finalBitmap = Bitmap.createScaledBitmap(bitmap, radius, radius,
            finalBitmap = bitmap;
        Bitmap output = Bitmap.createBitmap(finalBitmap.getWidth(),
                finalBitmap.getHeight(), Bitmap.Config.ARGB_8888);
        Canvas canvas = new Canvas(output);

        final Paint paint = new Paint();
        final Rect rect = new Rect(0, 0, finalBitmap.getWidth(),

        final RectF rectf = new RectF(0, 0, finalBitmap.getWidth(),

        canvas.drawARGB(0, 0, 0, 0);
        //Set Required Radius Here
        int yourRadius = 7;
        canvas.drawRoundRect(rectf, yourRadius, yourRadius, paint);
        paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_IN));
        canvas.drawBitmap(finalBitmap, rect, rect, paint);

        return output;


Javascript add method to object

You can make bar a function making it a method. = function(passvariable){  };

As a property it would just be assigned a string, data type or boolean = "a place";

ORA-03113: end-of-file on communication channel after long inactivity in ASP.Net app

Check that there isn't a firewall that is ending the connection after certain period of time (this was the cause of a similar problem we had)

Embedding a media player in a website using HTML


      Automatically play music files on your website when a page loads

  <embed src="YourMusic.mp3" autostart="true" loop="true" width="2" height="0">


Using Linq select list inside list

After my previous answer disaster, I'm going to try something else.

List<Model> usrList  = 
(list.Where(n => n.application == "applicationame").ToList());
usrList.ForEach(n => n.users.RemoveAll(n => n.surname != "surname"));

How to set timeout in Retrofit library?

These answers were outdated for me, so here's how it worked out.

Add OkHttp, in my case the version is 3.3.1:

compile 'com.squareup.okhttp3:okhttp:3.3.1'

Then before building your Retrofit, do this:

OkHttpClient okHttpClient = new OkHttpClient().newBuilder()
    .connectTimeout(60, TimeUnit.SECONDS)
    .readTimeout(60, TimeUnit.SECONDS)
    .writeTimeout(60, TimeUnit.SECONDS)
return new Retrofit.Builder()

Specify JDK for Maven to use

You could also set the JDK for Maven in a file in your home directory ~/.mavenrc:


This environment variable will be checked by the mvn script and used when present:

  if [ -f "$HOME/.mavenrc" ] ; then
    . "$HOME/.mavenrc"

What does it mean when Statement.executeUpdate() returns -1?

As the statement executed is not actually DML (eg UPDATE, INSERT or EXECUTE), but a piece of T-SQL which contains DML, I suspect it is not treated as an update-query.

Section of the JDBC 4.1 specification states something (rather hard to interpret btw):

When the method execute returns true, the method getResultSet is called to retrieve the ResultSet object. When execute returns false, the method getUpdateCount returns an int. If this number is greater than or equal to zero, it indicates the update count returned by the statement. If it is -1, it indicates that there are no more results.

Given this information, I guess that executeUpdate() internally does an execute(), and then - as execute() will return false - it will return the value of getUpdateCount(), which in this case - in accordance with the JDBC spec - will return -1.

This is further corroborated by the fact 1) that the Javadoc for Statement.executeUpdate() says:

Returns: either (1) the row count for SQL Data Manipulation Language (DML) statements or (2) 0 for SQL statements that return nothing

And 2) that the Javadoc for Statement.getUpdateCount() specifies:

the current result as an update count; -1 if the current result is a ResultSet object or there are no more results

Just to clarify: given the Javadoc for executeUpdate() the behavior is probably wrong, but it can be explained.

Also as I commented elsewhere, the -1 might just indicate: maybe something was changed, but we simply don't know, or we can't give an accurate number of changes (eg because in this example it is a piece of T-SQL that is executed).

When is the init() function run?

Take for example a framework or a library you're designing for other users, these users eventually will have a main function in their code in order to execute their app. If the user directly imports a sub-package of your library's project then the init of that sub-package will be called(once) first of all. The same for the root package of the library, etc...

There are many times when you may want a code block to be executed without the existence of a main func, directly or not.

If you, as the developer of the imaginary library, import your library's sub-package that has an init function, it will be called first and once, you don't have a main func but you need to make sure that some variables, or a table, will be initialized before the calls of other functions.

A good thing to remember and not to worry about, is that: the init always execute once per application.

init execution happens:

  1. right before the init function of the "caller" package,
  2. before the, optionally, main func,
  3. but after the package-level variables, var = [...] or cost = [...],

When you import a package it will run all of its init functions, by order.

I'll will give a very good example of an init function. It will add mime types to a standard go's library named mime and a package-level function will use the mime standard package directly to get the custom mime types that are already be initialized at its init function:

package mime

import (

var types = map[string]string{
    ".3dm":       "x-world/x-3dmf",
    ".3dmf":      "x-world/x-3dmf",
    ".7z":        "application/x-7z-compressed",
    ".a":         "application/octet-stream",
    ".aab":       "application/x-authorware-bin",
    ".aam":       "application/x-authorware-map",
    ".aas":       "application/x-authorware-seg",
    ".abc":       "text/vndabc",
    ".ace":       "application/x-ace-compressed",
    ".acgi":      "text/html",
    ".afl":       "video/animaflex",
    ".ai":        "application/postscript",
    ".aif":       "audio/aiff",
    ".aifc":      "audio/aiff",
    ".aiff":      "audio/aiff",
    ".aim":       "application/x-aim",
    ".aip":       "text/x-audiosoft-intra",
    ".alz":       "application/x-alz-compressed",
    ".ani":       "application/x-navi-animation",
    ".aos":       "application/x-nokia-9000-communicator-add-on-software",
    ".aps":       "application/mime",
    ".apk":       "application/",
    ".arc":       "application/x-arc-compressed",
    ".arj":       "application/arj",
    ".art":       "image/x-jg",
    ".asf":       "video/x-ms-asf",
    ".asm":       "text/x-asm",
    ".asp":       "text/asp",
    ".asx":       "application/x-mplayer2",
    ".au":        "audio/basic",
    ".avi":       "video/x-msvideo",
    ".avs":       "video/avs-video",
    ".bcpio":     "application/x-bcpio",
    ".bin":       "application/mac-binary",
    ".bmp":       "image/bmp",
    ".boo":       "application/book",
    ".book":      "application/book",
    ".boz":       "application/x-bzip2",
    ".bsh":       "application/x-bsh",
    ".bz2":       "application/x-bzip2",
    ".bz":        "application/x-bzip",
    ".c++":       "text/plain",
    ".c":         "text/x-c",
    ".cab":       "application/",
    ".cat":       "application/vndms-pkiseccat",
    ".cc":        "text/x-c",
    ".ccad":      "application/clariscad",
    ".cco":       "application/x-cocoa",
    ".cdf":       "application/cdf",
    ".cer":       "application/pkix-cert",
    ".cha":       "application/x-chat",
    ".chat":      "application/x-chat",
    ".chrt":      "application/vnd.kde.kchart",
    ".class":     "application/java",
    ".com":       "text/plain",
    ".conf":      "text/plain",
    ".cpio":      "application/x-cpio",
    ".cpp":       "text/x-c",
    ".cpt":       "application/mac-compactpro",
    ".crl":       "application/pkcs-crl",
    ".crt":       "application/pkix-cert",
    ".crx":       "application/x-chrome-extension",
    ".csh":       "text/x-scriptcsh",
    ".css":       "text/css",
    ".csv":       "text/csv",
    ".cxx":       "text/plain",
    ".dar":       "application/x-dar",
    ".dcr":       "application/x-director",
    ".deb":       "application/x-debian-package",
    ".deepv":     "application/x-deepv",
    ".def":       "text/plain",
    ".der":       "application/x-x509-ca-cert",
    ".dif":       "video/x-dv",
    ".dir":       "application/x-director",
    ".divx":      "video/divx",
    ".dl":        "video/dl",
    ".dmg":       "application/x-apple-diskimage",
    ".doc":       "application/msword",
    ".dot":       "application/msword",
    ".dp":        "application/commonground",
    ".drw":       "application/drafting",
    ".dump":      "application/octet-stream",
    ".dv":        "video/x-dv",
    ".dvi":       "application/x-dvi",
    ".dwf":       "drawing/x-dwf=(old)",
    ".dwg":       "application/acad",
    ".dxf":       "application/dxf",
    ".dxr":       "application/x-director",
    ".el":        "text/x-scriptelisp",
    ".elc":       "application/x-bytecodeelisp=(compiled=elisp)",
    ".eml":       "message/rfc822",
    ".env":       "application/x-envoy",
    ".eps":       "application/postscript",
    ".es":        "application/x-esrehber",
    ".etx":       "text/x-setext",
    ".evy":       "application/envoy",
    ".exe":       "application/octet-stream",
    ".f77":       "text/x-fortran",
    ".f90":       "text/x-fortran",
    ".f":         "text/x-fortran",
    ".fdf":       "application/vndfdf",
    ".fif":       "application/fractals",
    ".fli":       "video/fli",
    ".flo":       "image/florian",
    ".flv":       "video/x-flv",
    ".flx":       "text/vndfmiflexstor",
    ".fmf":       "video/x-atomic3d-feature",
    ".for":       "text/x-fortran",
    ".fpx":       "image/vndfpx",
    ".frl":       "application/freeloader",
    ".funk":      "audio/make",
    ".g3":        "image/g3fax",
    ".g":         "text/plain",
    ".gif":       "image/gif",
    ".gl":        "video/gl",
    ".gsd":       "audio/x-gsm",
    ".gsm":       "audio/x-gsm",
    ".gsp":       "application/x-gsp",
    ".gss":       "application/x-gss",
    ".gtar":      "application/x-gtar",
    ".gz":        "application/x-compressed",
    ".gzip":      "application/x-gzip",
    ".h":         "text/x-h",
    ".hdf":       "application/x-hdf",
    ".help":      "application/x-helpfile",
    ".hgl":       "application/vndhp-hpgl",
    ".hh":        "text/x-h",
    ".hlb":       "text/x-script",
    ".hlp":       "application/hlp",
    ".hpg":       "application/vndhp-hpgl",
    ".hpgl":      "application/vndhp-hpgl",
    ".hqx":       "application/binhex",
    ".hta":       "application/hta",
    ".htc":       "text/x-component",
    ".htm":       "text/html",
    ".html":      "text/html",
    ".htmls":     "text/html",
    ".htt":       "text/webviewhtml",
    ".htx":       "text/html",
    ".ice":       "x-conference/x-cooltalk",
    ".ico":       "image/x-icon",
    ".ics":       "text/calendar",
    ".icz":       "text/calendar",
    ".idc":       "text/plain",
    ".ief":       "image/ief",
    ".iefs":      "image/ief",
    ".iges":      "application/iges",
    ".igs":       "application/iges",
    ".ima":       "application/x-ima",
    ".imap":      "application/x-httpd-imap",
    ".inf":       "application/inf",
    ".ins":       "application/x-internett-signup",
    ".ip":        "application/x-ip2",
    ".isu":       "video/x-isvideo",
    ".it":        "audio/it",
    ".iv":        "application/x-inventor",
    ".ivr":       "i-world/i-vrml",
    ".ivy":       "application/x-livescreen",
    ".jam":       "audio/x-jam",
    ".jav":       "text/x-java-source",
    ".java":      "text/x-java-source",
    ".jcm":       "application/x-java-commerce",
    ".jfif-tbnl": "image/jpeg",
    ".jfif":      "image/jpeg",
    ".jnlp":      "application/x-java-jnlp-file",
    ".jpe":       "image/jpeg",
    ".jpeg":      "image/jpeg",
    ".jpg":       "image/jpeg",
    ".jps":       "image/x-jps",
    ".js":        "application/javascript",
    ".json":      "application/json",
    ".jut":       "image/jutvision",
    ".kar":       "audio/midi",
    ".karbon":    "application/vnd.kde.karbon",
    ".kfo":       "application/vnd.kde.kformula",
    ".flw":       "application/vnd.kde.kivio",
    ".kml":       "application/",
    ".kmz":       "application/",
    ".kon":       "application/vnd.kde.kontour",
    ".kpr":       "application/vnd.kde.kpresenter",
    ".kpt":       "application/vnd.kde.kpresenter",
    ".ksp":       "application/vnd.kde.kspread",
    ".kwd":       "application/vnd.kde.kword",
    ".kwt":       "application/vnd.kde.kword",
    ".ksh":       "text/x-scriptksh",
    ".la":        "audio/nspaudio",
    ".lam":       "audio/x-liveaudio",
    ".latex":     "application/x-latex",
    ".lha":       "application/lha",
    ".lhx":       "application/octet-stream",
    ".list":      "text/plain",
    ".lma":       "audio/nspaudio",
    ".log":       "text/plain",
    ".lsp":       "text/x-scriptlisp",
    ".lst":       "text/plain",
    ".lsx":       "text/x-la-asf",
    ".ltx":       "application/x-latex",
    ".lzh":       "application/octet-stream",
    ".lzx":       "application/lzx",
    ".m1v":       "video/mpeg",
    ".m2a":       "audio/mpeg",
    ".m2v":       "video/mpeg",
    ".m3u":       "audio/x-mpegurl",
    ".m":         "text/x-m",
    ".man":       "application/x-troff-man",
    ".manifest":  "text/cache-manifest",
    ".map":       "application/x-navimap",
    ".mar":       "text/plain",
    ".mbd":       "application/mbedlet",
    ".mc$":       "application/x-magic-cap-package-10",
    ".mcd":       "application/mcad",
    ".mcf":       "text/mcf",
    ".mcp":       "application/netmc",
    ".me":        "application/x-troff-me",
    ".mht":       "message/rfc822",
    ".mhtml":     "message/rfc822",
    ".mid":       "application/x-midi",
    ".midi":      "application/x-midi",
    ".mif":       "application/x-frame",
    ".mime":      "message/rfc822",
    ".mjf":       "audio/x-vndaudioexplosionmjuicemediafile",
    ".mjpg":      "video/x-motion-jpeg",
    ".mm":        "application/base64",
    ".mme":       "application/base64",
    ".mod":       "audio/mod",
    ".moov":      "video/quicktime",
    ".mov":       "video/quicktime",
    ".movie":     "video/x-sgi-movie",
    ".mp2":       "audio/mpeg",
    ".mp3":       "audio/mpeg3",
    ".mp4":       "video/mp4",
    ".mpa":       "audio/mpeg",
    ".mpc":       "application/x-project",
    ".mpe":       "video/mpeg",
    ".mpeg":      "video/mpeg",
    ".mpg":       "video/mpeg",
    ".mpga":      "audio/mpeg",
    ".mpp":       "application/vndms-project",
    ".mpt":       "application/x-project",
    ".mpv":       "application/x-project",
    ".mpx":       "application/x-project",
    ".mrc":       "application/marc",
    ".ms":        "application/x-troff-ms",
    ".mv":        "video/x-sgi-movie",
    ".my":        "audio/make",
    ".mzz":       "application/x-vndaudioexplosionmzz",
    ".nap":       "image/naplps",
    ".naplps":    "image/naplps",
    ".nc":        "application/x-netcdf",
    ".ncm":       "application/vndnokiaconfiguration-message",
    ".nif":       "image/x-niff",
    ".niff":      "image/x-niff",
    ".nix":       "application/x-mix-transfer",
    ".nsc":       "application/x-conference",
    ".nvd":       "application/x-navidoc",
    ".o":         "application/octet-stream",
    ".oda":       "application/oda",
    ".odb":       "application/vnd.oasis.opendocument.database",
    ".odc":       "application/vnd.oasis.opendocument.chart",
    ".odf":       "application/vnd.oasis.opendocument.formula",
    ".odg":       "application/",
    ".odi":       "application/vnd.oasis.opendocument.image",
    ".odm":       "application/vnd.oasis.opendocument.text-master",
    ".odp":       "application/vnd.oasis.opendocument.presentation",
    ".ods":       "application/vnd.oasis.opendocument.spreadsheet",
    ".odt":       "application/vnd.oasis.opendocument.text",
    ".oga":       "audio/ogg",
    ".ogg":       "audio/ogg",
    ".ogv":       "video/ogg",
    ".omc":       "application/x-omc",
    ".omcd":      "application/x-omcdatamaker",
    ".omcr":      "application/x-omcregerator",
    ".otc":       "application/vnd.oasis.opendocument.chart-template",
    ".otf":       "application/vnd.oasis.opendocument.formula-template",
    ".otg":       "application/",
    ".oth":       "application/vnd.oasis.opendocument.text-web",
    ".oti":       "application/vnd.oasis.opendocument.image-template",
    ".otm":       "application/vnd.oasis.opendocument.text-master",
    ".otp":       "application/vnd.oasis.opendocument.presentation-template",
    ".ots":       "application/vnd.oasis.opendocument.spreadsheet-template",
    ".ott":       "application/vnd.oasis.opendocument.text-template",
    ".p10":       "application/pkcs10",
    ".p12":       "application/pkcs-12",
    ".p7a":       "application/x-pkcs7-signature",
    ".p7c":       "application/pkcs7-mime",
    ".p7m":       "application/pkcs7-mime",
    ".p7r":       "application/x-pkcs7-certreqresp",
    ".p7s":       "application/pkcs7-signature",
    ".p":         "text/x-pascal",
    ".part":      "application/pro_eng",
    ".pas":       "text/pascal",
    ".pbm":       "image/x-portable-bitmap",
    ".pcl":       "application/vndhp-pcl",
    ".pct":       "image/x-pict",
    ".pcx":       "image/x-pcx",
    ".pdb":       "chemical/x-pdb",
    ".pdf":       "application/pdf",
    ".pfunk":     "audio/make",
    ".pgm":       "image/x-portable-graymap",
    ".pic":       "image/pict",
    ".pict":      "image/pict",
    ".pkg":       "application/x-newton-compatible-pkg",
    ".pko":       "application/vndms-pkipko",
    ".pl":        "text/x-scriptperl",
    ".plx":       "application/x-pixclscript",
    ".pm4":       "application/x-pagemaker",
    ".pm5":       "application/x-pagemaker",
    ".pm":        "text/x-scriptperl-module",
    ".png":       "image/png",
    ".pnm":       "application/x-portable-anymap",
    ".pot":       "application/mspowerpoint",
    ".pov":       "model/x-pov",
    ".ppa":       "application/vndms-powerpoint",
    ".ppm":       "image/x-portable-pixmap",
    ".pps":       "application/mspowerpoint",
    ".ppt":       "application/mspowerpoint",
    ".ppz":       "application/mspowerpoint",
    ".pre":       "application/x-freelance",
    ".prt":       "application/pro_eng",
    ".ps":        "application/postscript",
    ".psd":       "application/octet-stream",
    ".pvu":       "paleovu/x-pv",
    ".pwz":       "application/vndms-powerpoint",
    ".py":        "text/x-scriptphyton",
    ".pyc":       "application/x-bytecodepython",
    ".qcp":       "audio/vndqcelp",
    ".qd3":       "x-world/x-3dmf",
    ".qd3d":      "x-world/x-3dmf",
    ".qif":       "image/x-quicktime",
    ".qt":        "video/quicktime",
    ".qtc":       "video/x-qtc",
    ".qti":       "image/x-quicktime",
    ".qtif":      "image/x-quicktime",
    ".ra":        "audio/x-pn-realaudio",
    ".ram":       "audio/x-pn-realaudio",
    ".rar":       "application/x-rar-compressed",
    ".ras":       "application/x-cmu-raster",
    ".rast":      "image/cmu-raster",
    ".rexx":      "text/x-scriptrexx",
    ".rf":        "image/vndrn-realflash",
    ".rgb":       "image/x-rgb",
    ".rm":        "application/vndrn-realmedia",
    ".rmi":       "audio/mid",
    ".rmm":       "audio/x-pn-realaudio",
    ".rmp":       "audio/x-pn-realaudio",
    ".rng":       "application/ringing-tones",
    ".rnx":       "application/vndrn-realplayer",
    ".roff":      "application/x-troff",
    ".rp":        "image/vndrn-realpix",
    ".rpm":       "audio/x-pn-realaudio-plugin",
    ".rt":        "text/vndrn-realtext",
    ".rtf":       "text/richtext",
    ".rtx":       "text/richtext",
    ".rv":        "video/vndrn-realvideo",
    ".s":         "text/x-asm",
    ".s3m":       "audio/s3m",
    ".s7z":       "application/x-7z-compressed",
    ".saveme":    "application/octet-stream",
    ".sbk":       "application/x-tbook",
    ".scm":       "text/x-scriptscheme",
    ".sdml":      "text/plain",
    ".sdp":       "application/sdp",
    ".sdr":       "application/sounder",
    ".sea":       "application/sea",
    ".set":       "application/set",
    ".sgm":       "text/x-sgml",
    ".sgml":      "text/x-sgml",
    ".sh":        "text/x-scriptsh",
    ".shar":      "application/x-bsh",
    ".shtml":     "text/x-server-parsed-html",
    ".sid":       "audio/x-psid",
    ".skd":       "application/x-koan",
    ".skm":       "application/x-koan",
    ".skp":       "application/x-koan",
    ".skt":       "application/x-koan",
    ".sit":       "application/x-stuffit",
    ".sitx":      "application/x-stuffitx",
    ".sl":        "application/x-seelogo",
    ".smi":       "application/smil",
    ".smil":      "application/smil",
    ".snd":       "audio/basic",
    ".sol":       "application/solids",
    ".spc":       "text/x-speech",
    ".spl":       "application/futuresplash",
    ".spr":       "application/x-sprite",
    ".sprite":    "application/x-sprite",
    ".spx":       "audio/ogg",
    ".src":       "application/x-wais-source",
    ".ssi":       "text/x-server-parsed-html",
    ".ssm":       "application/streamingmedia",
    ".sst":       "application/vndms-pkicertstore",
    ".step":      "application/step",
    ".stl":       "application/sla",
    ".stp":       "application/step",
    ".sv4cpio":   "application/x-sv4cpio",
    ".sv4crc":    "application/x-sv4crc",
    ".svf":       "image/vnddwg",
    ".svg":       "image/svg+xml",
    ".svr":       "application/x-world",
    ".swf":       "application/x-shockwave-flash",
    ".t":         "application/x-troff",
    ".talk":      "text/x-speech",
    ".tar":       "application/x-tar",
    ".tbk":       "application/toolbook",
    ".tcl":       "text/x-scripttcl",
    ".tcsh":      "text/x-scripttcsh",
    ".tex":       "application/x-tex",
    ".texi":      "application/x-texinfo",
    ".texinfo":   "application/x-texinfo",
    ".text":      "text/plain",
    ".tgz":       "application/gnutar",
    ".tif":       "image/tiff",
    ".tiff":      "image/tiff",
    ".tr":        "application/x-troff",
    ".tsi":       "audio/tsp-audio",
    ".tsp":       "application/dsptype",
    ".tsv":       "text/tab-separated-values",
    ".turbot":    "image/florian",
    ".txt":       "text/plain",
    ".uil":       "text/x-uil",
    ".uni":       "text/uri-list",
    ".unis":      "text/uri-list",
    ".unv":       "application/i-deas",
    ".uri":       "text/uri-list",
    ".uris":      "text/uri-list",
    ".ustar":     "application/x-ustar",
    ".uu":        "text/x-uuencode",
    ".uue":       "text/x-uuencode",
    ".vcd":       "application/x-cdlink",
    ".vcf":       "text/x-vcard",
    ".vcard":     "text/x-vcard",
    ".vcs":       "text/x-vcalendar",
    ".vda":       "application/vda",
    ".vdo":       "video/vdo",
    ".vew":       "application/groupwise",
    ".viv":       "video/vivo",
    ".vivo":      "video/vivo",
    ".vmd":       "application/vocaltec-media-desc",
    ".vmf":       "application/vocaltec-media-file",
    ".voc":       "audio/voc",
    ".vos":       "video/vosaic",
    ".vox":       "audio/voxware",
    ".vqe":       "audio/x-twinvq-plugin",
    ".vqf":       "audio/x-twinvq",
    ".vql":       "audio/x-twinvq-plugin",
    ".vrml":      "application/x-vrml",
    ".vrt":       "x-world/x-vrt",
    ".vsd":       "application/x-visio",
    ".vst":       "application/x-visio",
    ".vsw":       "application/x-visio",
    ".w60":       "application/wordperfect60",
    ".w61":       "application/wordperfect61",
    ".w6w":       "application/msword",
    ".wav":       "audio/wav",
    ".wb1":       "application/x-qpro",
    ".wbmp":      "image/vnd.wap.wbmp",
    ".web":       "application/vndxara",
    ".wiz":       "application/msword",
    ".wk1":       "application/x-123",
    ".wmf":       "windows/metafile",
    ".wml":       "text/vnd.wap.wml",
    ".wmlc":      "application/vnd.wap.wmlc",
    ".wmls":      "text/vnd.wap.wmlscript",
    ".wmlsc":     "application/vnd.wap.wmlscriptc",
    ".word":      "application/msword",
    ".wp5":       "application/wordperfect",
    ".wp6":       "application/wordperfect",
    ".wp":        "application/wordperfect",
    ".wpd":       "application/wordperfect",
    ".wq1":       "application/x-lotus",
    ".wri":       "application/mswrite",
    ".wrl":       "application/x-world",
    ".wrz":       "model/vrml",
    ".wsc":       "text/scriplet",
    ".wsrc":      "application/x-wais-source",
    ".wtk":       "application/x-wintalk",
    ".x-png":     "image/png",
    ".xbm":       "image/x-xbitmap",
    ".xdr":       "video/x-amt-demorun",
    ".xgz":       "xgl/drawing",
    ".xif":       "image/vndxiff",
    ".xl":        "application/excel",
    ".xla":       "application/excel",
    ".xlb":       "application/excel",
    ".xlc":       "application/excel",
    ".xld":       "application/excel",
    ".xlk":       "application/excel",
    ".xll":       "application/excel",
    ".xlm":       "application/excel",
    ".xls":       "application/excel",
    ".xlt":       "application/excel",
    ".xlv":       "application/excel",
    ".xlw":       "application/excel",
    ".xm":        "audio/xm",
    ".xml":       "text/xml",
    ".xmz":       "xgl/movie",
    ".xpix":      "application/x-vndls-xpix",
    ".xpm":       "image/x-xpixmap",
    ".xsr":       "video/x-amt-showrun",
    ".xwd":       "image/x-xwd",
    ".xyz":       "chemical/x-pdb",
    ".z":         "application/x-compress",
    ".zip":       "application/zip",
    ".zoo":       "application/octet-stream",
    ".zsh":       "text/x-scriptzsh",
    ".docx":      "application/vnd.openxmlformats-officedocument.wordprocessingml.document",
    ".docm":      "application/",
    ".dotx":      "application/vnd.openxmlformats-officedocument.wordprocessingml.template",
    ".dotm":      "application/",
    ".xlsx":      "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet",
    ".xlsm":      "application/",
    ".xltx":      "application/vnd.openxmlformats-officedocument.spreadsheetml.template",
    ".xltm":      "application/",
    ".xlsb":      "application/",
    ".xlam":      "application/",
    ".pptx":      "application/vnd.openxmlformats-officedocument.presentationml.presentation",
    ".pptm":      "application/",
    ".ppsx":      "application/vnd.openxmlformats-officedocument.presentationml.slideshow",
    ".ppsm":      "application/",
    ".potx":      "application/vnd.openxmlformats-officedocument.presentationml.template",
    ".potm":      "application/",
    ".ppam":      "application/",
    ".sldx":      "application/vnd.openxmlformats-officedocument.presentationml.slide",
    ".sldm":      "application/",
    ".thmx":      "application/",
    ".onetoc":    "application/onenote",
    ".onetoc2":   "application/onenote",
    ".onetmp":    "application/onenote",
    ".onepkg":    "application/onenote",
    ".xpi":       "application/x-xpinstall",

func init() {
    for ext, typ := range types {
        // skip errors
        mime.AddExtensionType(ext, typ)

// typeByExtension returns the MIME type associated with the file extension ext.
// The extension ext should begin with a leading dot, as in ".html".
// When ext has no associated type, typeByExtension returns "".
// Extensions are looked up first case-sensitively, then case-insensitively.
// The built-in table is small but on unix it is augmented by the local
// system's mime.types file(s) if available under one or more of these
// names:
//   /etc/mime.types
//   /etc/apache2/mime.types
//   /etc/apache/mime.types
// On Windows, MIME types are extracted from the registry.
// Text types have the charset parameter set to "utf-8" by default.
func TypeByExtension(fullfilename string) string {
    ext := filepath.Ext(fullfilename)
    typ := mime.TypeByExtension(ext)

    // mime.TypeByExtension returns as text/plain; | charset=utf-8 the static .js (not always)
    if ext == ".js" && (typ == "text/plain" || typ == "text/plain; charset=utf-8") {

        if ext == ".js" {
            typ = "application/javascript"
    return typ

Hope that helped you and other users, don't hesitate to post again if you have more questions!

close fxml window by code, javafx

I found a nice solution which does not need an event to be triggered:

private Button cancelButton;

close(new Event(cancelButton, stage, null));

private void close(Event event) {

Setting action for back button in navigation controller

Overriding navigationBar(_ navigationBar:shouldPop): This is not a good idea, even if it works. for me it generated random crashes on navigating back. I advise you to just override the back button by removing the default backButton from navigationItem and creating a custom back button like below:

override func viewDidLoad(){
   navigationItem.leftBarButton = .init(title: "Go Back", ... , action: #selector(myCutsomBackAction) 



Building on previous responses with UIAlert in Swift5 in a Asynchronous way

protocol NavigationControllerBackButtonDelegate {
    func shouldPopOnBackButtonPress(_ completion: @escaping (Bool) -> ())

extension UINavigationController: UINavigationBarDelegate {
    public func navigationBar(_ navigationBar: UINavigationBar, shouldPop item: UINavigationItem) -> Bool {
        if viewControllers.count < navigationBar.items!.count {
            return true
        // Check if we have a view controller that wants to respond to being popped
        if let viewController = topViewController as? NavigationControllerBackButtonDelegate {
            viewController.shouldPopOnBackButtonPress { shouldPop in
                if (shouldPop) {
                    /// on confirm => pop
                    DispatchQueue.main.async {
                        self.popViewController(animated: true)
                } else {
                    /// on cancel => do nothing
            /// return false => so navigator will cancel the popBack
            /// until user confirm or cancel
            return false
            DispatchQueue.main.async {
                self.popViewController(animated: true)
        return true

On your controller

extension MyController: NavigationControllerBackButtonDelegate {
    func shouldPopOnBackButtonPress(_ completion: @escaping (Bool) -> ()) {
        let msg = "message"
        /// show UIAlert
        alertAttention(msg: msg, actions: [
            .init(title: "Continuer", style: .destructive, handler: { _ in
            .init(title: "Annuler", style: .cancel, handler: { _ in


PHP Pass variable to next page

HTML / HTTP is stateless, in other words, what you did / saw on the previous page, is completely unconnected with the current page. Except if you use something like sessions, cookies or GET / POST variables. Sessions and cookies are quite easy to use, with session being by far more secure than cookies. More secure, but not completely secure.


//On page 1
$_SESSION['varname'] = $var_value;

//On page 2
$var_value = $_SESSION['varname'];

Remember to run the session_start(); statement on both these pages before you try to access the $_SESSION array, and also before any output is sent to the browser.


//One page 1
$_COOKIE['varname'] = $var_value;

//On page 2
$var_value = $_COOKIE['varname'];

The big difference between sessions and cookies is that the value of the variable will be stored on the server if you're using sessions, and on the client if you're using cookies. I can't think of any good reason to use cookies instead of sessions, except if you want data to persist between sessions, but even then it's perhaps better to store it in a DB, and retrieve it based on a username or id.


You can add the variable in the link to the next page:

<a href="page2.php?varname=<?php echo $var_value ?>">Page2</a>

This will create a GET variable.

Another way is to include a hidden field in a form that submits to page two:

<form method="get" action="page2.php">
    <input type="hidden" name="varname" value="var_value">
    <input type="submit">

And then on page two:

//Using GET
$var_value = $_GET['varname'];

//Using POST
$var_value = $_POST['varname'];

//Using GET, POST or COOKIE.
$var_value = $_REQUEST['varname'];

Just change the method for the form to post if you want to do it via post. Both are equally insecure, although GET is easier to hack.

The fact that each new request is, except for session data, a totally new instance of the script caught me when I first started coding in PHP. Once you get used to it, it's quite simple though.

jquery: animate scrollLeft

First off I should point out that css animations would probably work best if you are doing this a lot but I ended getting the desired effect by wrapping .scrollLeft inside .animate


    $('.swipeBox').animate( { scrollLeft: '+=460' }, 1000);

    $('.swipeBox').animate( { scrollLeft: '-=460' }, 1000);

The second parameter is speed, and you can also add a third parameter if you are using smooth scrolling of some sort.

IE7 Z-Index Layering Issues

I encountered this issue, but on a large project where HTML changes had to be requested and became a whole issue, so I was looking for a pure css solution.

By placing position:relative; z-index:-1 on my main body content my header drop down content suddenly displayed above the body content in ie7 (it was already displaying without issue in all other browsers and in ie8+)

The problem with that was then this disabled all hover and click actions on all content in the element with the z-index:-1 so i went to the parent element of the whole page and gave it a position:relative; z-index:1

Which fixed the issue and retained the correct layering functionality.

Feels a bit hacky, but worked as required.

GIT clone repo across local file system in windows

You can specify the remote’s URL by applying the UNC path to the file protocol. This requires you to use four slashes:

git clone file:////<host>/<share>/<path>

For example, if your main machine has the IP and the computer name main, and it has a share named code which itself is a git repository, then both of the following commands should work equally:

git clone file:////main/code
git clone file:////

If the Git repository is in a subdirectory, simply append the path:

git clone file:////main/code/project-repository
git clone file:////

How to change the color of an svg element?

To change color of SVG element I have found out a way while inspecting Google search box search icon below:

.search_icon {
  color: red;
  fill: currentColor;
  display: inline-block;
  width: 100px;
  height: 100px;
<span class="search_icon">
    <svg focusable="false" xmlns="" viewBox="0 0 24 24"><path d="M15.5 14h-.79l-.28-.27A6.471 6.471 0 0 0 16 9.5 6.5 6.5 0 1 0 9.5 16c1.61 0 3.09-.59 4.23-1.57l.27.28v.79l5 4.99L20.49 19l-4.99-5zm-6 0C7.01 14 5 11.99 5 9.5S7.01 5 9.5 5 14 7.01 14 9.5 11.99 14 9.5 14z"></path></svg>

I have used span element with "display:inline-block", height, width and setting a particular style "color: red; fill: currentColor;" to that span tag which is inherited by the child svg element.

JavaScript - onClick to get the ID of the clicked button

Although it's 8+ years late, in reply to @Amc_rtty, to get dynamically generated IDs from (my) HTML, I used the index of the php loop to increment the button IDs. I concatenated the same indices to the ID of the input element, hence I ended up with id="tableview1" and button id="1" and so on.

$tableView .= "<td><input type='hidden' value='http://".$_SERVER['HTTP_HOST']."/sql/update.php?id=".$mysql_rows[0]."&table=".$theTable."'id='tableview".$mysql_rows[0]."'><button type='button' onclick='loadDoc(event)' id='".$mysql_rows[0]."'>Edit</button></td>";

In the javascript, I stored the button click in a variable and added it to the element.

function loadDoc(e) {
  var btn =;
  var xhttp = new XMLHttpRequest();
  var page = document.getElementById("tableview"+btn).value;
  //other Ajax stuff

TypeError: 'bool' object is not callable

You do cls.isFilled = True. That overwrites the method called isFilled and replaces it with the value True. That method is now gone and you can't call it anymore. So when you try to call it again you get an error, since it's not there anymore.

The solution is use a different name for the variable than you do for the method.

Failed to execute 'postMessage' on 'DOMWindow': The target origin provided does not match the recipient window's origin ('null')

In My Case, Im trying to pass messages from Salesforce Marketing Cloud Custom Activity(Domain 1) to Heroku(Domain 2) on load.

The Error Appeared in console, when I loaded my original html page from where message is being passed.

Issue I noticed after reading many blogs is that, the receiver page is not loaded yet. i.e

I need to debug from my receiver page not from sender page.

Simple but glad if it helps anyone.

Typescript: Type 'string | undefined' is not assignable to type 'string'

To avoid the compilation error I used

let name1:string = || '';

And then validate the empty string.

Vertical rulers in Visual Studio Code

In addition to global "editor.rulers" setting, it's also possible to set this on a per-language level.

For example, style guides for Python projects often specify either 79 or 120 characters vs. Git commit messages should be no longer than 50 characters.

So in your settings.json, you'd put:

"[git-commit]": {"editor.rulers": [50]},
"[python]": {
    "editor.rulers": [

Change selected value of kendo ui dropdownlist

It's possible to "natively" select by value:;

Display an array in a readable/hierarchical format

Instead of



print "<pre>";
print "</pre>";

What is the MySQL JDBC driver connection string?

Here is a little code from my side :)

needed driver:


download: here (Platform Independent)

connection string in one line:


example code:

public static void testDB(){
    try {
    } catch (ClassNotFoundException e) {

    try {
        Connection connection = DriverManager.getConnection(
        if (connection != null) {
            Statement statement = connection.createStatement();
            if (statement != null) {
                ResultSet resultSet = statement.executeQuery("select * from test");
                if (resultSet != null) {
                    ResultSetMetaData meta = resultSet.getMetaData();
                    int length = meta.getColumnCount();
                        for(int i = 1; i <= length; i++){
                            System.out.println(meta.getColumnName(i) + ": " + resultSet.getString(meta.getColumnName(i)));
    } catch (Throwable throwable) {

Popup window in winform c#

"But the thing is I also want to be able to add textboxes etc in this popup window thru the form designer."

It's unclear from your description at what stage in the development process you're in. If you haven't already figured it out, to create a new Form you click on Project --> Add Windows Form, then type in a name for the form and hit the "Add" button. Now you can add controls to your form as you'd expect.

When it comes time to display it, follow the advice of the other posts to create an instance and call Show() or ShowDialog() as appropriate.

How do you disable viewport zooming on Mobile Safari?

For the people looking for an iOS 10 solution, user-scaleable=no is disabled in Safari for iOS 10. The reason is that Apple is trying to improve accessibility by allowing people to zoom on web pages.

From release notes:

To improve accessibility on websites in Safari, users can now pinch-to-zoom even when a website sets user-scalable=no in the viewport.

So as far as I understand, we are sh** out of luck.

How to find a hash key containing a matching value

According to ruby doc key(value) is the method to find the key on the base of value.

ROLE = {"customer" => 1, "designer" => 2, "admin" => 100}

it will return the "designer".

Error when trying vagrant up

There appears to be something wrong with the embedded curl program in Vagrant. Following the advice above I just renamed it (just in case I wanted it back) and vagrant up began to work as expected.

On my mac:

? .vagrant.d sudo mv /opt/vagrant/embedded/bin/curl /opt/vagrant/embedded/bin/curlOLD Password:

CORS: credentials mode is 'include'

Customizing CORS for Angular 5 and Spring Security (Cookie base solution)

On the Angular side required adding option flag withCredentials: true for Cookie transport:

constructor(public http: HttpClient) {

public get(url: string = ''): Observable<any> {
    return this.http.get(url, { withCredentials: true });

On Java server-side required adding CorsConfigurationSource for configuration CORS policy:

public class WebSecurityConfig extends WebSecurityConfigurerAdapter {

    CorsConfigurationSource corsConfigurationSource() {
        CorsConfiguration configuration = new CorsConfiguration();
        // This Origin header you can see that in Network tab
        configuration.setAllowedOrigins(Arrays.asList("http:/url_1", "http:/url_2")); 
        UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource();
        source.registerCorsConfiguration("/**", configuration);
        return source;

    protected void configure(HttpSecurity http) throws Exception {

Method configure(HttpSecurity http) by default will use corsConfigurationSource for http.cors()

Pycharm and sys.argv arguments

On PyCharm Community or Professional Edition 2019.1+ :

  1. From the menu bar click Run -> Edit Configurations
  2. Add your arguments in the Parameters textbox (for example file2.txt file3.txt, or --myFlag myArg --anotherFlag mySecondArg)
  3. Click Apply
  4. Click OK

How to send email to multiple recipients with addresses stored in Excel?

You have to loop through every cell in the range "D3:D6" and construct your To string. Simply assigning it to a variant will not solve the purpose. EmailTo becomes an array if you assign the range directly to it. You can do this as well but then you will have to loop through the array to create your To string

Is this what you are trying? (TRIED AND TESTED)

Option Explicit

Sub Mail_workbook_Outlook_1()
     'Working in 2000-2010
     'This example send the last saved version of the Activeworkbook
    Dim OutApp As Object
    Dim OutMail As Object
    Dim emailRng As Range, cl As Range
    Dim sTo As String

    Set emailRng = Worksheets("Selections").Range("D3:D6")

    For Each cl In emailRng 
        sTo = sTo & ";" & cl.Value

    sTo = Mid(sTo, 2)

    Set OutApp = CreateObject("Outlook.Application")
    Set OutMail = OutApp.CreateItem(0)

    On Error Resume Next
    With OutMail
        .To = sTo
        .CC = "[email protected];[email protected]"
        .BCC = ""
        .Subject = "RMA #" & Worksheets("RMA").Range("E1")
        .Body = "Attached to this email is RMA #" & _
        Worksheets("RMA").Range("E1") & _
        ". Please follow the instructions for your department included in this form."
        .Attachments.Add ActiveWorkbook.FullName
         'You can add other files also like this
         '.Attachments.Add ("C:\test.txt")

    End With
    On Error GoTo 0

    Set OutMail = Nothing
    Set OutApp = Nothing
End Sub

Why do I need to explicitly push a new branch?

The actual reason is that, in a new repo (git init), there is no branch (no master, no branch at all, zero branches)

So when you are pushing for the first time to an empty upstream repo (generally a bare one), that upstream repo has no branch of the same name.


In both cases, since the upstream empty repo has no branch:

  • there is no matching named branch yet
  • there is no upstream branch at all (with or without the same name! Tracking or not)

That means your local first push has no idea:

  • where to push
  • what to push (since it cannot find any upstream branch being either recorded as a remote tracking branch, and/or having the same name)

So you need at least to do a:

git push origin master

But if you do only that, you:

  • will create an upstream master branch on the upstream (now non-empty repo): good.
  • won't record that the local branch 'master' needs to be pushed to upstream (origin) 'master' (upstream branch): bad.

That is why it is recommended, for the first push, to do a:

git push -u origin master

That will record origin/master as a remote tracking branch, and will enable the next push to automatically push master to origin/master.

git checkout master
git push

And that will work too with push policies 'current' or 'upstream'.
In each case, after the initial git push -u origin master, a simple git push will be enough to continue pushing master to the right upstream branch.

Converting newline formatting from Mac to Windows

  1. Install dos2unix with homebrew
  2. Run find ./ -type f -exec dos2unix {} \; to recursively convert all line-endings within current folder

Hibernate Criteria for Dates

If the column is a timestamp you can do the following:

            criteria.add(Restrictions.sqlRestriction("TRUNC(COLUMN) >= TO_DATE('" + dataFrom + "','dd/mm/yyyy')"));
            criteria.add(Restrictions.sqlRestriction("TRUNC(COLUMN) <= TO_DATE('" + dataTo + "','dd/mm/yyyy')"));

        resultDB = criteria.list();

How to call function of one php file from another php file and pass parameters to it?

files directory:





function sum(a,b){
 return a+b;
function product(a,b){
return a*b;


require_once "functions.php";
echo "sum of two numbers ". sum(4,2);
echo "<br>"; //  create break line
echo "product of two numbers ".product(2,3);

The Output Is :

sum of two numbers 6 product of two numbers 6

Note: don't write public before function. Public, private, these modifiers can only use when you create class.

ArrayList initialization equivalent to array initialization

This is how it is done using the fluent interface of the op4j Java library (1.1. was released Dec '10) :-

List<String> names = Op.onListFor("Ryan", "Julie", "Bob").get();

It's a very cool library that saves you a tonne of time.

How to change the remote a branch is tracking?

git fetch origin
git checkout --track -b local_branch_name origin/branch_name


git fetch
git checkout -b local_branch_name origin/branch_name

Strip HTML from strings in Python

You can write your own function:

def StripTags(text):
     finished = 0
     while not finished:
         finished = 1
         start = text.find("<")
         if start >= 0:
             stop = text[start:].find(">")
             if stop >= 0:
                 text = text[:start] + text[start+stop+1:]
                 finished = 0
     return text

SQL- Ignore case while searching for a string

Use something like this -




Cannot make file No such file or directory

If the directory ../.foo/bar/ doesn't exist, you can't create a file there, so make sure you create the directory first.

Try something like this:

File f = new File("somedirname1/somedirname2/somefilename");
if (!f.getParentFile().exists())
if (!f.exists())

Error in file(file, "rt") : cannot open the connection

I had a same issue .I removed the extension from the file name.Example my file name was saved as xyz. csv. i saved it as xyz.

Where can I find Android source code online?

Everything is mirrored on Some of the code is also mirrored on github.

Contacts is here for example.

Since December 2019, you can use the new official public code search tool for AOSP: There's also the Android official source browser (based on Gitiles) has a web view of many of the different parts that make up android. Some of the projects (such as Kernel) have been removed and it now only points you to clonable git repositories.

To get all the code locally, you can use the repo helper program, or you can just clone individual repositories.

And others:

Get folder up one level

echo dirname(__DIR__);

But note the __DIR__ constant was added in PHP 5.3.0.

AngularJS : Prevent error $digest already in progress when calling $scope.$apply()

        let $timeoutPromise = null;
        $timeoutPromise = $timeout(() => {
        }, 0, false);

Here is good solution to avoid this error and avoid $apply

you can combine this with debounce(0) if calling based on external event. Above is the 'debounce' we are using, and full example of code

.factory('debounce', [
    function ($timeout) {

        return function (func, wait, apply) {
            // apply default is true for $timeout
            if (apply !== false) {
                apply = true;

            var promise;
            return function () {
                var cntx = this,
                    args = arguments;
                promise = $timeout(function () {
                    return func.apply(cntx, args);
                }, wait, apply);
                return promise;

and the code itself to listen some event and call $digest only on $scope you need

        let $timeoutPromise = null;
        let $update = debounce(function () {
            $timeoutPromise = $timeout(() => {
            }, 0, false);
        }, 0, false);

        let $unwatchModelChanges = $scope.$root.$on('updatePropertiesInspector', function () {

        $scope.$on('$destroy', () => {

How do I print out the contents of an object in Rails for easy debugging?

inspect is great but sometimes not good enough. E.g. BigDecimal prints like this: #<BigDecimal:7ff49f5478b0,'0.1E2',9(18)>.

To have full control over what's printed you could redefine to_s or inspect methods. Or create your own one to not confuse future devs too much.

  class Something < ApplicationRecord

    def to_s{ |k, v| { k => v.to_s } }.inject(:merge)


This will apply a method (i.e. to_s) to all attributes. This example will get rid of the ugly BigDecimals.

You can also redefine a handful of attributes only:

  def to_s
    attributes.merge({ my_attribute: my_attribute.to_s })

You can also create a mix of the two or somehow add associations.

sudo: docker-compose: command not found

Or, just add your binary path into the PATH. At the end of the bashrc:

export PATH=$PATH:/home/user/.local/bin/

save the file and run:

source .bashrc

and the command will work.

Python: How to use RegEx in an if statement?

if re.match(regex, content):

You could also use depending on how you want it to match.

How correctly produce JSON by RESTful web service?

@Path ("Employee")
public JSONObject postEmployee(JSONObject jsonObject)throws Exception{
    return jsonObject;

How do I convert certain columns of a data frame to become factors?

Given the following sample

myData <- data.frame(A=rep(1:2, 3), B=rep(1:3, 2), Pulse=20:25)  


myData$A <-as.factor(myData$A)
myData$B <-as.factor(myData$B)

or you could select your columns altogether and wrap it up nicely:

# select columns
cols <- c("A", "B")
myData[,cols] <- data.frame(apply(myData[cols], 2, as.factor))

levels(myData$A) <- c("long", "short")
levels(myData$B) <- c("1kg", "2kg", "3kg")

To obtain

> myData
      A   B Pulse
1  long 1kg    20
2 short 2kg    21
3  long 3kg    22
4 short 1kg    23
5  long 2kg    24
6 short 3kg    25

Monitor the Graphics card usage

From Unix.SE: A simple command-line utility called gpustat now exists:

It is free software (MIT license) and is packaged in pypi. It is a wrapper of nvidia-smi.

'ls' is not recognized as an internal or external command, operable program or batch file

If you want to use Unix shell commands on Windows, you can use Windows Powershell, which includes both Windows and Unix commands as aliases. You can find more info on it in the documentation.

PowerShell supports aliases to refer to commands by alternate names. Aliasing allows users with experience in other shells to use common command names that they already know for similar operations in PowerShell.

The PowerShell equivalents may not produce identical results. However, the results are close enough that users can do work without knowing the PowerShell command name.

Check variable equality against a list of values

If you have access to Underscore, you can use the following:

if (_.contains([1, 3, 12], foo)) {
  // ...

contains used to work in Lodash as well (prior to V4), now you have to use includes

if (_.includes([1, 3, 12], foo)) {

How do I avoid the specification of the username and password at every git push?

My Solution on Windows:

  1. Right click at directory to push and select "Git Bash Here".
  2. ssh-keygen -t rsa (Press enter for all values)
  3. Check terminal for: Your public key has been saved in /c/Users/<your_user_name_here>/.ssh/
  4. Copy public key from specified file.
  5. Go to your GitHub profile => Settings => SSH and GPG keys => New SSH key => Paste your SSH key there => Save

Find the max of 3 numbers in Java with different data types

Math.max only takes two arguments. If you want the maximum of three, use Math.max(MY_INT1, Math.max(MY_INT2, MY_DOUBLE2)).

Best way to create a simple python web service

Have a look at werkzeug. Werkzeug started as a simple collection of various utilities for WSGI applications and has become one of the most advanced WSGI utility modules. It includes a powerful debugger, full featured request and response objects, HTTP utilities to handle entity tags, cache control headers, HTTP dates, cookie handling, file uploads, a powerful URL routing system and a bunch of community contributed addon modules.

It includes lots of cool tools to work with http and has the advantage that you can use it with wsgi in different environments (cgi, fcgi, apache/mod_wsgi or with a plain simple python server for debugging).

How to remove item from array by value?

This can be a global function or a method of a custom object, if you aren't allowed to add to native prototypes. It removes all of the items from the array that match any of the arguments.

Array.prototype.remove = function() {
    var what, a = arguments, L = a.length, ax;
    while (L && this.length) {
        what = a[--L];
        while ((ax = this.indexOf(what)) !== -1) {
            this.splice(ax, 1);
    return this;

var ary = ['three', 'seven', 'eleven'];


/*  returned value: (Array)

To make it a global-

function removeA(arr) {
    var what, a = arguments, L = a.length, ax;
    while (L > 1 && arr.length) {
        what = a[--L];
        while ((ax= arr.indexOf(what)) !== -1) {
            arr.splice(ax, 1);
    return arr;
var ary = ['three', 'seven', 'eleven'];
removeA(ary, 'seven');

/*  returned value: (Array)

And to take care of IE8 and below-

if(!Array.prototype.indexOf) {
    Array.prototype.indexOf = function(what, i) {
        i = i || 0;
        var L = this.length;
        while (i < L) {
            if(this[i] === what) return i;
        return -1;

Imply bit with constant 1 or 0 in SQL Server

No, but you could cast the whole expression rather than the sub-components of that expression. Actually, that probably makes it less readable in this case.

Read text file into string. C++ ifstream

It looks like you are trying to parse each line. You've been shown by another answer how to use getline in a loop to seperate each line. The other tool you are going to want is istringstream, to seperate each token.

std::string line;
while(std::getline(file, line))
    std::istringstream iss(line);
    std::string token;
    while (iss >> token)
        // do something with token

Regex for remove everything after | (with | )

In a .txt file opened with Notepad++,
press Ctrl-F
go in the tab "Replace"
write the regex pattern \|.+ in the space Find what
and let the space Replace with blank

Then tick the choice matches newlines after the choice Regular expression
and press two times on the Replace button

Making a PowerShell POST request if a body param starts with '@'

@Frode F. gave the right answer.

By the Way Invoke-WebRequest also prints you the 200 OK and a lot of bla, bla, bla... which might be useful but I still prefer the Invoke-RestMethod which is lighter.

Also, keep in mind that you need to use | ConvertTo-Json for the body only, not the header:

$body = @{
 "OptionalEmail"="[email protected]"
} | ConvertTo-Json

$header = @{

Invoke-RestMethod -Uri "http://MyServer/WSVistaWebClient/RESTService.svc/member/search" -Method 'Post' -Body $body -Headers $header | ConvertTo-HTML

and you can then append a | ConvertTo-HTML at the end of the request for better readability

Maven Error: Could not find or load main class

add this to your pom.xml file:

       <transformer implementation="org.apache.maven.plugins.shade.resource.ServicesResourceTransformer"/>
       <transformer implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">

and add the class name of your project (full path) along with the package name like "com.packageName.className" which consists of the main method having "run" method in it. And instead of your "???" write ${mainClass} which will automatically get the className which you have mentioned above.

Then try command mvn clean install and mvn -jar "jar_file_name.jar" server "yaml_file_name.yml"

I hope it will work normally and server will start at the specified port.

What is a race condition?

You can prevent race condition, if you use "Atomic" classes. The reason is just the thread don't separate operation get and set, example is below:

AtomicInteger ai = new AtomicInteger(2);

As a result, you will have 7 in link "ai". Although you did two actions, but the both operation confirm the same thread and no one other thread will interfere to this, that means no race conditions!

Reliable way for a Bash script to get the full path to itself


BASEDIR=$(readlink -f $0 | xargs dirname)

Fancy operators are not needed.

HTML table sort

Check if you could go with any of the below mentioned JQuery plugins. Simply awesome and provide wide range of options to work through, and less pains to integrate. :) - Flexgrid - Data tables.

If not, you need to have a link to those table headers that calls a server-side script to invoke the sort.

ObservableCollection not noticing when Item in it changes (even with INotifyPropertyChanged)

To Trigger OnChange in ObservableCollection List

  1. Get index of selected Item
  2. Remove the item from the Parent
  3. Add the item at same index in parent


int index = NotificationDetails.IndexOf(notificationDetails);
NotificationDetails.Insert(index, notificationDetails);

What does $ mean before a string?

It signifies string interpolation.

It will protect you because it is adding compilation time protection on the string evaluation.

You will no longer get an exception with string.Format("{0}{1}",secondParamIsMissing)

Perform commands over ssh with Python

Or you can just use commands.getstatusoutput:

   commands.getstatusoutput("ssh machine 1 'your script'")

I used it extensively and it works great.

In Python 2.6+, use subprocess.check_output.

How can I uninstall Ruby on ubuntu?

You can use sudo apt remove ruby

Pandas Split Dataframe into two Dataframes at a specific row


df1 = datasX.iloc[:, :72]
df2 = datasX.iloc[:, 72:]

(iloc docs)

How can I map True/False to 1/0 in a Pandas DataFrame?

You also can do this directly on Frames

In [104]: df = DataFrame(dict(A = True, B = False),index=range(3))

In [105]: df
      A      B
0  True  False
1  True  False
2  True  False

In [106]: df.dtypes
A    bool
B    bool
dtype: object

In [107]: df.astype(int)
   A  B
0  1  0
1  1  0
2  1  0

In [108]: df.astype(int).dtypes
A    int64
B    int64
dtype: object

pandas: How do I split text in a column into multiple rows?

This splits the Seatblocks by space and gives each its own row.

In [43]: df
   CustNum     CustomerName  ItemQty Item                 Seatblocks  ItemExt
0    32363  McCartney, Paul        3  F04               2:218:10:4,6       60
1    31316     Lennon, John       25  F01  1:13:36:1,12 1:13:37:1,13      300

In [44]: s = df['Seatblocks'].str.split(' ').apply(Series, 1).stack()

In [45]: s.index = s.index.droplevel(-1) # to line up with df's index

In [46]: = 'Seatblocks' # needs a name to join

In [47]: s
0    2:218:10:4,6
1    1:13:36:1,12
1    1:13:37:1,13
Name: Seatblocks, dtype: object

In [48]: del df['Seatblocks']

In [49]: df.join(s)
   CustNum     CustomerName  ItemQty Item  ItemExt    Seatblocks
0    32363  McCartney, Paul        3  F04       60  2:218:10:4,6
1    31316     Lennon, John       25  F01      300  1:13:36:1,12
1    31316     Lennon, John       25  F01      300  1:13:37:1,13

Or, to give each colon-separated string in its own column:

In [50]: df.join(s.apply(lambda x: Series(x.split(':'))))
   CustNum     CustomerName  ItemQty Item  ItemExt  0    1   2     3
0    32363  McCartney, Paul        3  F04       60  2  218  10   4,6
1    31316     Lennon, John       25  F01      300  1   13  36  1,12
1    31316     Lennon, John       25  F01      300  1   13  37  1,13

This is a little ugly, but maybe someone will chime in with a prettier solution.

Setting CSS pseudo-class rules from JavaScript

In jquery you can easily set hover pseudo classes.

$(this).css("background-color", "yellow");
}, function(){
$(this).css("background-color", "pink");

YouTube: How to present embed video with sound muted

<iframe width="560" height="315" src=";autoplay=1&controls=1&loop=1" rel=0&amp frameborder="0" allowfullscreen></iframe>

How do you add an array to another array in Ruby and not end up with a multi-dimensional result?

Elaborating on @Pilcrow's answer the only suitable answer for huge arrays is concat (+) since is fast and does not allocate a new object to be garbage-collected when operating inside a loop.

Here's the benchmark:

require 'benchmark'

huge_ary_1 = { rand(5_000_000..30_000_00) }

huge_ary_2 = { rand(35_000_000..55_000_00) } do |bm|
  p '-------------------CONCAT ----------------' { huge_ary_1.concat(huge_ary_2) }

  p '------------------- PUSH ----------------' { huge_ary_1.push(*huge_ary_2)  }


       user     system      total        real
"-------------------CONCAT ----------------"
  0.000000   0.000000   0.000000 (  0.009388)
"------------------- PUSH ----------------"
  example/array_concat_vs_push.rb:13:in `block (2 levels) in <main>': stack level too deep (SystemStackError)

As you can see using push throws an ERROR: stack level too deep (SystemStackError) when the arrays are big enough.

Change route params without reloading in Angular 2

For anyone like me finding this question the following might be useful.

I had a similar problem and initially tried using location.go and location.replaceState as suggested in other answers here. However I ran into problems when I had to navigate to another page on the app because the navigation was relative to the current route and the current route wasn't being updated by location.go or location.replaceState (the router doesn't know anything about what these do to the URL)

In essence I needed a solution that DIDN'T reload the page/component when the route parameter changed but DID update the route state internally.

I ended up using query parameters. You can find more about it here:

So if you need to do something like save an order and get an order ID you can update your page URL like shown below. Updating a centre location and related data on a map would be similar

// let's say we're saving an order. Initally the URL is just blah/orders
save(orderId) {
    // [Here we would call back-end to save the order in the database]

    this.router.navigate(['orders'], { queryParams: { id: orderId } });
    // now the URL is blah/orders?id:1234. We don't reload the orders
    // page or component so get desired behaviour of not seeing any 
    // flickers or resetting the page.

and you keep track of it within the ngOnInit method like:

ngOnInit() {
    this.orderId = this.route
        .map(params => params.get('id') || null);
    // orderID is up-to-date with what is saved in database now, or if
    // nothing is saved and hence no id query paramter the orderId variable
    // is simply null.
    // [You can load the order here from its ID if this suits your design]

If you need to go direct to the order page with a new (unsaved) order you can do:


Or if you need to go direct to the order page for an existing (saved) order you can do:

this.router.navigate(['orders'], { queryParams: { id: '1234' } });

Converting string to date in mongodb

I had some strings in the MongoDB Stored wich had to be reformated to a proper and valid dateTime field in the mongodb.

here is my code for the special date format: "2014-03-12T09:14:19.5303017+01:00"

but you can easyly take this idea and write your own regex to parse the date formats:

// format: "2014-03-12T09:14:19.5303017+01:00"
var myregexp = /(....)-(..)-(..)T(..):(..):(..)\.(.+)([\+-])(..)/;

db.Product.find().forEach(function(doc) { 
   var matches = myregexp.exec(doc.metadata.insertTime);

   if myregexp.test(doc.metadata.insertTime)) {
       var offset = matches[9] * (matches[8] == "+" ? 1 : -1);
       var hours = matches[4]-(-offset)+1
       var date = new Date(matches[1], matches[2]-1, matches[3],hours, matches[5], matches[6], matches[7] / 10000.0)
       db.Product.update({_id : doc._id}, {$set : {"metadata.insertTime" : date}})
       print("succsessfully updated");
    } else {
        print("not updated");

Copy the entire contents of a directory in C#

Try this:

Process proc = new Process();
proc.StartInfo.UseShellExecute = true;
proc.StartInfo.FileName = Path.Combine(Environment.SystemDirectory, "xcopy.exe");
proc.StartInfo.Arguments = @"C:\source C:\destination /E /I";

Your xcopy arguments may vary but you get the idea.

Convert JSON string to dict using Python

When I started using json, I was confused and unable to figure it out for some time, but finally I got what I wanted
Here is the simple solution

import json
m = {'id': 2, 'name': 'hussain'}
n = json.dumps(m)
o = json.loads(n)
print(o['id'], o['name'])

twitter bootstrap typeahead ajax example

Edit: typeahead is no longer bundled in Bootstrap 3. Check out:

As of Bootstrap 2.1.0 up to 2.3.2, you can do this:

    source: function (query, process) {
        return $.get('/typeahead', { query: query }, function (data) {
            return process(data.options);

To consume JSON data like this:

    "options": [
        "Option 1",
        "Option 2",
        "Option 3",
        "Option 4",
        "Option 5"

Note that the JSON data must be of the right mime type (application/json) so jQuery recognizes it as JSON.

Calling a Sub and returning a value

Sub don't return values and functions don't have side effects.

Sometimes you want both side effect and return value.

This is easy to be done once you know that VBA passes arguments by default by reference so you can write your code in this way:

Sub getValue(retValue as Long)
    retValue = 42 
End SUb 

Sub Main()
    Dim retValue As Long
    getValue retValue 
End SUb

JavaScript string encryption and decryption?

How about CryptoJS?

It's a solid crypto library, with a lot of functionality. It implements hashers, HMAC, PBKDF2 and ciphers. In this case ciphers is what you need. Check out the quick-start quide on the project's homepage.

You could do something like with the AES:

<script src=""></script>

    var encryptedAES = CryptoJS.AES.encrypt("Message", "My Secret Passphrase");
    var decryptedBytes = CryptoJS.AES.decrypt(encryptedAES, "My Secret Passphrase");
    var plaintext = decryptedBytes.toString(CryptoJS.enc.Utf8);

As for security, at the moment of my writing AES algorithm is thought to be unbroken

Edit :

Seems online URL is down & you can use the downloaded files for encryption from below given link & place the respective files in your root folder of the application.

or used other CDN like

Select datatype of the field in postgres

The information schema views and pg_typeof() return incomplete type information. Of these answers, psql gives the most precise type information. (The OP might not need such precise information, but should know the limitations.)

create domain test_domain as varchar(15);

create table test (
  test_id test_domain, 
  test_vc varchar(15), 
  test_n numeric(15, 3), 
  big_n bigint,
  ip_addr inet

Using psql and \d public.test correctly shows the use of the data type test_domain, the length of varchar(n) columns, and the precision and scale of numeric(p, s) columns.

sandbox=# \d public.test
             Table "public.test"
 Column  |         Type          | Modifiers
 test_id | test_domain           |
 test_vc | character varying(15) |
 test_n  | numeric(15,3)         |
 big_n   | bigint                |
 ip_addr | inet                  |

This query against an information_schema view does not show the use of test_domain at all. It also doesn't report the details of varchar(n) and numeric(p, s) columns.

select column_name, data_type 
from information_schema.columns 
where table_catalog = 'sandbox'
  and table_schema = 'public'
  and table_name = 'test';
 column_name |     data_type
 test_id     | character varying
 test_vc     | character varying
 test_n      | numeric
 big_n       | bigint
 ip_addr     | inet

You might be able to get all that information by joining other information_schema views, or by querying the system tables directly. psql -E might help with that.

The function pg_typeof() correctly shows the use of test_domain, but doesn't report the details of varchar(n) and numeric(p, s) columns.

select pg_typeof(test_id) as test_id, 
       pg_typeof(test_vc) as test_vc,
       pg_typeof(test_n) as test_n,
       pg_typeof(big_n) as big_n,
       pg_typeof(ip_addr) as ip_addr
from test;
   test_id   |      test_vc      | test_n  | big_n  | ip_addr
 test_domain | character varying | numeric | bigint | inet

PHP 5.4 Call-time pass-by-reference - Easy fix available?

For anyone who, like me, reads this because they need to update a giant legacy project to 5.6: as the answers here point out, there is no quick fix: you really do need to find each occurrence of the problem manually, and fix it.

The most convenient way I found to find all problematic lines in a project (short of using a full-blown static code analyzer, which is very accurate but I don't know any that take you to the correct position in the editor right away) was using Visual Studio Code, which has a nice PHP linter built in, and its search feature which allows searching by Regex. (Of course, you can use any IDE/Code editor for this that does PHP linting and Regex searches.)

Using this regex:


it is possible to search project-wide for the occurrence of &$ only in lines that are not a function definition.

This still turns up a lot of false positives, but it does make the job easier.

VSCode's search results browser makes walking through and finding the offending lines super easy: you just click through each result, and look out for those that the linter underlines red. Those you need to fix.

"cannot resolve symbol R" in Android Studio

I am facing an error 'Unable to resolve symbol R' the R appears in java file in red. I've solved it.

  1. Do not save any image with Capital letters like ABC.png. First delete the image or rename it.
  2. Clean project
  3. Rebuild Project

Simple way to unzip a .zip file using zlib

Minizip does have an example programs to demonstrate its usage - the files are called minizip.c and miniunz.c.

Update: I had a few minutes so I whipped up this quick, bare bones example for you. It's very smelly C, and I wouldn't use it without major improvements. Hopefully it's enough to get you going for now.

// uzip.c - Simple example of using the minizip API.
// Do not use this code as is! It is educational only, and probably
// riddled with errors and leaks!
#include <stdio.h>
#include <string.h>

#include "unzip.h"

#define dir_delimter '/'
#define MAX_FILENAME 512
#define READ_SIZE 8192

int main( int argc, char **argv )
    if ( argc < 2 )
        printf( "usage:\n%s {file to unzip}\n", argv[ 0 ] );
        return -1;

    // Open the zip file
    unzFile *zipfile = unzOpen( argv[ 1 ] );
    if ( zipfile == NULL )
        printf( "%s: not found\n" );
        return -1;

    // Get info about the zip file
    unz_global_info global_info;
    if ( unzGetGlobalInfo( zipfile, &global_info ) != UNZ_OK )
        printf( "could not read file global info\n" );
        unzClose( zipfile );
        return -1;

    // Buffer to hold data read from the zip file.
    char read_buffer[ READ_SIZE ];

    // Loop to extract all files
    uLong i;
    for ( i = 0; i < global_info.number_entry; ++i )
        // Get info about current file.
        unz_file_info file_info;
        char filename[ MAX_FILENAME ];
        if ( unzGetCurrentFileInfo(
            NULL, 0, NULL, 0 ) != UNZ_OK )
            printf( "could not read file info\n" );
            unzClose( zipfile );
            return -1;

        // Check if this entry is a directory or file.
        const size_t filename_length = strlen( filename );
        if ( filename[ filename_length-1 ] == dir_delimter )
            // Entry is a directory, so create it.
            printf( "dir:%s\n", filename );
            mkdir( filename );
            // Entry is a file, so extract it.
            printf( "file:%s\n", filename );
            if ( unzOpenCurrentFile( zipfile ) != UNZ_OK )
                printf( "could not open file\n" );
                unzClose( zipfile );
                return -1;

            // Open a file to write out the data.
            FILE *out = fopen( filename, "wb" );
            if ( out == NULL )
                printf( "could not open destination file\n" );
                unzCloseCurrentFile( zipfile );
                unzClose( zipfile );
                return -1;

            int error = UNZ_OK;
                error = unzReadCurrentFile( zipfile, read_buffer, READ_SIZE );
                if ( error < 0 )
                    printf( "error %d\n", error );
                    unzCloseCurrentFile( zipfile );
                    unzClose( zipfile );
                    return -1;

                // Write data to file.
                if ( error > 0 )
                    fwrite( read_buffer, error, 1, out ); // You should check return of fwrite...
            } while ( error > 0 );

            fclose( out );

        unzCloseCurrentFile( zipfile );

        // Go the the next entry listed in the zip file.
        if ( ( i+1 ) < global_info.number_entry )
            if ( unzGoToNextFile( zipfile ) != UNZ_OK )
                printf( "cound not read next file\n" );
                unzClose( zipfile );
                return -1;

    unzClose( zipfile );

    return 0;

I built and tested it with MinGW/MSYS on Windows like this:

contrib/minizip/$ gcc -I../.. -o unzip uzip.c unzip.c ioapi.c ../../libz.a
contrib/minizip/$ ./unzip.exe /j/

How to empty the content of a div

you can .remove() each child:

const div = document.querySelector('')
while(div.firstChild) div.firstChild.remove()

Jquery to get the id of selected value from dropdown

Try the change event and selected selector

    var optId = $(this).find('option:selected').attr('id')

PHP Excel Header

The problem is you typed the wrong file extension for excel file. you used .xsl instead of xls.

I know i came in late but it can help future readers of this post.

Access Controller method from another controller in Laravel 5

You can access the controller by instantiating it and calling doAction: (put use Illuminate\Support\Facades\App; before the controller class declaration)

$controller = App::make('\App\Http\Controllers\YouControllerName');
$data = $controller->callAction('controller_method', $parameters);

Also note that by doing this you will not execute any of the middlewares declared on that controller.

How to disable Google asking permission to regularly check installed apps on my phone?

In Nexus 5, Go to Settings -> Google -> Security and uncheck "Scan device for Security threats" and "Improve harmful app detection".