Programs & Examples On #Glscene

GLScene is an OpenGL based 3D library for Delphi. It provides visual components and objects allowing description and rendering of 3D scenes in an easy, no-hassle, yet powerful manner.

Offset a background image from the right using CSS

If you would like to use this for adding arrows/other icons to a button for example then you could use css pseudo-elements?

If it's really a background-image for the whole button, I tend to incorporate the spacing into the image, and just use

background-position: right 0;

But if I have to add for example a designed arrow to a button, I tend to have this html:

<a href="[url]" class="read-more">Read more</a>

And tend to do the following with CSS:

.read-more{
    position: relative;
    padding: 6px 15px 6px 35px;//to create space on the right
    font-size: 13px;
    font-family: Arial;
}

.read-more:after{
    content: '';
    display: block;
    width: 10px;
    height: 15px;
    background-image: url('../images/btn-white-arrow-right.png');
    position: absolute;
    right: 12px;
    top: 10px;
}

By using the :after selector, I add a element using CSS just to contain this small icon. You could do the same by just adding a span or <i> element inside the a-element. But I think this is a cleaner way of adding icons to buttons and it is cross-browser supported.

you can check out the fiddle here: http://codepen.io/anon/pen/PNzYzZ

Centering controls within a form in .NET (Winforms)?

You can put the control you want to center inside a Panel and set the left and right padding values to something larger than the default. As long as they are equal and your control is anchored to the sides of the Panel, then it will appear centered in that Panel. Then you can anchor the container Panel to its parent as needed.

Print specific part of webpage

Instead of all the complicated JavaScript, you can actually achieve this with simple CSS: just use two CSS files, one for your normal screen display, and another for the display of ONLY the content you wish to print. In this latter file, hide everything you don't want printed, display only the pop up.

Remember to define the media attribute of both CSS files:

<link rel="stylesheet" href="screen-css.css" media="all" />
<link rel="stylesheet" href="print-css.css" media="print" />

using nth-child in tables tr td

table tr td:nth-child(2) {
    background: #ccc;
}

Working example: http://jsfiddle.net/gqr3J/

npm command to uninstall or prune unused packages in Node.js

If you're not worried about a couple minutes time to do so, a solution would be to rm -rf node_modules and npm install again to rebuild the local modules.

Regex date validation for yyyy-mm-dd

You can use this regex to get the yyyy-MM-dd format:

((?:19|20)\\d\\d)-(0?[1-9]|1[012])-([12][0-9]|3[01]|0?[1-9])

You can find example for date validation: How to validate date with regular expression.

Twitter Bootstrap: Print content of modal window

Another solution

Here is a new solution based on Bennett McElwee answer in the same question as mentioned below.

Tested with IE 9 & 10, Opera 12.01, Google Chrome 22 and Firefox 15.0.
jsFiddle example

1.) Add this CSS to your site:

@media screen {
  #printSection {
      display: none;
  }
}

@media print {
  body * {
    visibility:hidden;
  }
  #printSection, #printSection * {
    visibility:visible;
  }
  #printSection {
    position:absolute;
    left:0;
    top:0;
  }
}

2.) Add my JavaScript function

function printElement(elem, append, delimiter) {
    var domClone = elem.cloneNode(true);

    var $printSection = document.getElementById("printSection");

    if (!$printSection) {
        $printSection = document.createElement("div");
        $printSection.id = "printSection";
        document.body.appendChild($printSection);
    }

    if (append !== true) {
        $printSection.innerHTML = "";
    }

    else if (append === true) {
        if (typeof (delimiter) === "string") {
            $printSection.innerHTML += delimiter;
        }
        else if (typeof (delimiter) === "object") {
            $printSection.appendChild(delimiter);
        }
    }

    $printSection.appendChild(domClone);
}?

You're ready to print any element on your site!
Just call printElement() with your element(s) and execute window.print() when you're finished.

Note: If you want to modify the content before it is printed (and only in the print version), checkout this example (provided by waspina in the comments): http://jsfiddle.net/95ezN/121/

One could also use CSS in order to show the additional content in the print version (and only there).


Former solution

I think, you have to hide all other parts of the site via CSS.

It would be the best, to move all non-printable content into a separate DIV:

<body>
  <div class="non-printable">
    <!-- ... -->
  </div>

  <div class="printable">
    <!-- Modal dialog comes here -->
  </div>
</body>

And then in your CSS:

.printable { display: none; }

@media print
{
    .non-printable { display: none; }
    .printable { display: block; }
}

Credits go to Greg who has already answered a similar question: Print <div id="printarea"></div> only?

There is one problem in using JavaScript: the user cannot see a preview - at least in Internet Explorer!

How to vertically center a container in Bootstrap?

Update 2020

Bootstrap 4 includes flexbox, so the method of vertical centering is much easier and doesn't require extra CSS.

Just use the d-flex and align-items-center utility classes..

<div class="jumbotron d-flex align-items-center">
  <div class="container">
    content
  </div>
</div>

http://www.codeply.com/go/ui6ABmMTLv

Important: Vertical centering is relative to height. The parent container of the items you're attempting to center must have a defined height. If you want the height of the page use vh-100 or min-vh-100 on the parent! For example:

<div class="jumbotron d-flex align-items-center min-vh-100">
  <div class="container text-center">
    I am centered vertically
  </div>
</div>

Also see: https://stackoverflow.com/questions/42252443/vertical-align-center-in-bootstrap-4

How do I remove a submodule?

Removing git submodule

To remove a git submodule below 4 steps are needed.

  1. Remove the corresponding entry in .gitmodules file. Entry might be like mentioned below
[submodule "path_to_submodule"]
    path = path_to_submodule
    url = url_path_to_submodule
  1. Stage changes git add .gitmodules
  2. Remove the submodule directory git rm --cached <path_to_submodule>.
  3. Commit it git commit -m "Removed submodule xxx" and push.

Additional 2 more steps mentioned below are needed to clean submodule completely in local cloned copy.

  1. Remove the corresponding entry in .git/config file. Entry might be like mentioned below
[submodule "path_to_submodule"]
    url = url_path_to_submodule
  1. Do rm -rf .git/modules/path_to_submodule

These 5th and 6th steps does not creates any changes which needs commit.

module.exports vs. export default in Node.js and ES6

The issue is with

  • how ES6 modules are emulated in CommonJS
  • how you import the module

ES6 to CommonJS

At the time of writing this, no environment supports ES6 modules natively. When using them in Node.js you need to use something like Babel to convert the modules to CommonJS. But how exactly does that happen?

Many people consider module.exports = ... to be equivalent to export default ... and exports.foo ... to be equivalent to export const foo = .... That's not quite true though, or at least not how Babel does it.

ES6 default exports are actually also named exports, except that default is a "reserved" name and there is special syntax support for it. Lets have a look how Babel compiles named and default exports:

// input
export const foo = 42;
export default 21;

// output
"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
var foo = exports.foo = 42;
exports.default = 21; 

Here we can see that the default export becomes a property on the exports object, just like foo.

Import the module

We can import the module in two ways: Either using CommonJS or using ES6 import syntax.

Your issue: I believe you are doing something like:

var bar = require('./input');
new bar();

expecting that bar is assigned the value of the default export. But as we can see in the example above, the default export is assigned to the default property!

So in order to access the default export we actually have to do

var bar = require('./input').default;

If we use ES6 module syntax, namely

import bar from './input';
console.log(bar);

Babel will transform it to

'use strict';

var _input = require('./input');

var _input2 = _interopRequireDefault(_input);

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

console.log(_input2.default);

You can see that every access to bar is converted to access .default.

Angular 5 ngHide ngShow [hidden] not working

If you add [hidden]="true" to div, the actual thing that happens is adding a class [hidden] to this element conditionally with display: none

Please check the style of the element in the browser to ensure no other style affect the display property of an element like this:

enter image description here

If you found display of [hidden] class is overridden, you need to add this css code to your style:

[hidden] {
    display: none !important;
}

How to update two tables in one statement in SQL Server 2005?

You can write update statement for one table and then a trigger on first table update, which update second table

Convert string to Time

"16:23:01" doesn't match the pattern of "hh:mm:ss tt" - it doesn't have an am/pm designator, and 16 clearly isn't in a 12-hour clock. You're specifying that format in the parsing part, so you need to match the format of the existing data. You want:

DateTime dateTime = DateTime.ParseExact(time, "HH:mm:ss",
                                        CultureInfo.InvariantCulture);

(Note the invariant culture, not the current culture - assuming your input genuinely always uses colons.)

If you want to format it to hh:mm:ss tt, then you need to put that part in the ToString call:

lblClock.Text = date.ToString("hh:mm:ss tt", CultureInfo.CurrentCulture);

Or better yet (IMO) use "whatever the long time pattern is for the culture":

lblClock.Text = date.ToString("T", CultureInfo.CurrentCulture);

Also note that hh is unusual; typically you don't want to 0-left-pad the number for numbers less than 10.

(Also consider using my Noda Time API, which has a LocalTime type - a more appropriate match for just a "time of day".)

How to change node.js's console font color?

to color your output You can use examples from there:
https://help.ubuntu.com/community/CustomizingBashPrompt

Also a Gist for nodeJs

For example if you want part of the text in red color, just do console.log with:

"\033[31m this will be red \033[91m and this will be normal"

Based on that I've created "colog" extension for Node.js. You can install it using:

npm install colog

Repo and npm: https://github.com/dariuszp/colog

JavaScript click event listener on class

This should work. getElementsByClassName returns an array Array-like object(see edit) of the elements matching the criteria.

var elements = document.getElementsByClassName("classname");

var myFunction = function() {
    var attribute = this.getAttribute("data-myattribute");
    alert(attribute);
};

for (var i = 0; i < elements.length; i++) {
    elements[i].addEventListener('click', myFunction, false);
}

jQuery does the looping part for you, which you need to do in plain JavaScript.

If you have ES6 support you can replace your last line with:

    Array.from(elements).forEach(function(element) {
      element.addEventListener('click', myFunction);
    });

Note: Older browsers (like IE6, IE7, IE8) donĀ“t support getElementsByClassName and so they return undefined.


EDIT : Correction

getElementsByClassName doesnt return an array, but a HTMLCollection in most, or a NodeList in some browsers (Mozilla ref). Both of these types are Array-Like, (meaning that they have a length property and the objects can be accessed via their index), but are not strictly an Array or inherited from an Array. (meaning other methods that can be performed on an Array cannot be performed on these types)

Thanks to user @Nemo for pointing this out and having me dig in to fully understand.

Try catch statements in C

This is another way to do error handling in C which is more performant than using setjmp/longjmp. Unfortunately, it will not work with MSVC but if using only GCC/Clang is an option, then you might consider it. Specifically, it uses the "label as value" extension, which allows you to take the address of a label, store it in a value and and jump to it unconditionally. I'll present it using an example:

GameEngine *CreateGameEngine(GameEngineParams const *params)
{
    /* Declare an error handler variable. This will hold the address
       to jump to if an error occurs to cleanup pending resources.
       Initialize it to the err label which simply returns an
       error value (NULL in this example). The && operator resolves to
       the address of the label err */
    void *eh = &&err;

    /* Try the allocation */
    GameEngine *engine = malloc(sizeof *engine);
    if (!engine)
        goto *eh; /* this is essentially your "throw" */

    /* Now make sure that if we throw from this point on, the memory
       gets deallocated. As a convention you could name the label "undo_"
       followed by the operation to rollback. */
    eh = &&undo_malloc;

    /* Now carry on with the initialization. */
    engine->window = OpenWindow(...);
    if (!engine->window)
        goto *eh;   /* The neat trick about using approach is that you don't
                       need to remember what "undo" label to go to in code.
                       Simply go to *eh. */

    eh = &&undo_window_open;

    /* etc */

    /* Everything went well, just return the device. */
    return device;

    /* After the return, insert your cleanup code in reverse order. */
undo_window_open: CloseWindow(engine->window);
undo_malloc: free(engine);
err: return NULL;
}

If you so wish, you could refactor common code in defines, effectively implementing your own error-handling system.

/* Put at the beginning of a function that may fail. */
#define declthrows void *_eh = &&err

/* Cleans up resources and returns error result. */
#define throw goto *_eh

/* Sets a new undo checkpoint. */
#define undo(label) _eh = &&undo_##label

/* Throws if [condition] evaluates to false. */
#define check(condition) if (!(condition)) throw

/* Throws if [condition] evaluates to false. Then sets a new undo checkpoint. */
#define checkpoint(label, condition) { check(condition); undo(label); }

Then the example becomes

GameEngine *CreateGameEngine(GameEngineParams const *params)
{
    declthrows;

    /* Try the allocation */
    GameEngine *engine = malloc(sizeof *engine);
    checkpoint(malloc, engine);

    /* Now carry on with the initialization. */
    engine->window = OpenWindow(...);
    checkpoint(window_open, engine->window);

    /* etc */

    /* Everything went well, just return the device. */
    return device;

    /* After the return, insert your cleanup code in reverse order. */
undo_window_open: CloseWindow(engine->window);
undo_malloc: free(engine);
err: return NULL;
}

Using $window or $location to Redirect in AngularJS

Not sure from what version, but I use 1.3.14 and you can just use:

window.location.href = '/employee/1';

No need to inject $location or $window in the controller and no need to get the current host address.

How to add local .jar file dependency to build.gradle file?

You could also do this which would include all JARs in the local repository. This way you wouldn't have to specify it every time.

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
}

Abstract methods in Python

Something along these lines, using ABC

import abc

class Shape(object):
    __metaclass__ = abc.ABCMeta

    @abc.abstractmethod
    def method_to_implement(self, input):
        """Method documentation"""
        return

Also read this good tutorial: http://www.doughellmann.com/PyMOTW/abc/

You can also check out zope.interface which was used prior to introduction of ABC in python.

Unit testing private methods in C#

Yes, don't Test private methods.... The idea of a unit test is to test the unit by its public 'API'.

If you are finding you need to test a lot of private behavior, most likely you have a new 'class' hiding within the class you are trying to test, extract it and test it by its public interface.

One piece of advice / Thinking tool..... There is an idea that no method should ever be private. Meaning all methods should live on a public interface of an object.... if you feel you need to make it private, it most likely lives on another object.

This piece of advice doesn't quite work out in practice, but its mostly good advice, and often it will push people to decompose their objects into smaller objects.

LINQ: Distinct values

In addition to Jon Skeet's answer, you can also use the group by expressions to get the unique groups along w/ a count for each groups iterations:

var query = from e in doc.Elements("whatever")
            group e by new { id = e.Key, val = e.Value } into g
            select new { id = g.Key.id, val = g.Key.val, count = g.Count() };

Store JSON object in data attribute in HTML jQuery

!DOCTYPE html>

<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
$("#btn1").click(function()
{
person = new Object();
person.name = "vishal";
person.age =20;
    $("div").data(person);
});
  $("#btn2").click(function()
{
    alert($("div").data("name"));
});

});

</script>
<body>
<button id="btn1">Attach data to div element</button><br>
<button id="btn2">Get data attached to div element</button>
<div></div>
</body>


</html>

Anser:-Attach data to selected elements using an object with name/value pairs.
GET value using object propetis like name,age etc...

Setting HTTP headers

Never mind, I figured it out - I used the Set() method on Header() (doh!)

My handler looks like this now:

func saveHandler(w http.ResponseWriter, r *http.Request) {
    // allow cross domain AJAX requests
    w.Header().Set("Access-Control-Allow-Origin", "*")
}

Maybe this will help someone as caffeine deprived as myself sometime :)

ACCESS_FINE_LOCATION AndroidManifest Permissions Not Being Granted

You misspelled permission

<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />

UDP vs TCP, how much faster is it?

Which protocol performs better (in terms of throughput) - UDP or TCP - really depends on the network characteristics and the network traffic. Robert S. Barnes, for example, points out a scenario where TCP performs better (small-sized writes). Now, consider a scenario in which the network is congested and has both TCP and UDP traffic. Senders in the network that are using TCP, will sense the 'congestion' and cut down on their sending rates. However, UDP doesn't have any congestion avoidance or congestion control mechanisms, and senders using UDP would continue to pump in data at the same rate. Gradually, TCP senders would reduce their sending rates to bare minimum and if UDP senders have enough data to be sent over the network, they would hog up the majority of bandwidth available. So, in such a case, UDP senders will have greater throughput, as they get the bigger pie of the network bandwidth. In fact, this is an active research topic - How to improve TCP throughput in presence of UDP traffic. One way, that I know of, using which TCP applications can improve throughput is by opening multiple TCP connections. That way, even though, each TCP connection's throughput might be limited, the sum total of the throughput of all TCP connections may be greater than the throughput for an application using UDP.

How to set selected value from Combobox?

Use the SelectedIndex property for the respective employee status in the combo box.

ValueError: max() arg is an empty sequence

in one line,

v = max(v) if v else None

>>> v = []
>>> max(v)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ValueError: max() arg is an empty sequence
>>> v = max(v) if v else None
>>> v
>>> 

Construct pandas DataFrame from list of tuples of (row,col,values)

You can pivot your DataFrame after creating:

>>> df = pd.DataFrame(data)
>>> df.pivot(index=0, columns=1, values=2)
# avg DataFrame
1      c1     c2
0               
r1  avg11  avg12
r2  avg21  avg22
>>> df.pivot(index=0, columns=1, values=3)
# stdev DataFrame
1        c1       c2
0                   
r1  stdev11  stdev12
r2  stdev21  stdev22

What is the difference between a static and a non-static initialization code block

"final" guarantees that a variable must be initialized before end of object initializer code. Likewise "static final" guarantees that a variable will be initialized by the end of class initialization code. Omitting the "static" from your initialization code turns it into object initialization code; thus your variable no longer satisfies its guarantees.

java.util.Date to XMLGregorianCalendar

For those that might end up here looking for the opposite conversion (from XMLGregorianCalendar to Date):

XMLGregorianCalendar xcal = <assume this is initialized>;
java.util.Date dt = xcal.toGregorianCalendar().getTime();

Indentation shortcuts in Visual Studio

Tab to tab right, shift-tab to tab left.

Show/hide widgets in Flutter programmatically

Maybe you can use the Navigator function like this Navigator.of(context).pop();

posting hidden value

I'm not sure what you just did there, but from what I can tell this is what you're asking for:

bookingfacilities.php

<form action="successfulbooking.php" method="post">
    <input type="hidden" name="date" value="<?php echo $date; ?>">  
    <input type="submit" value="Submit Form">
</form>

successfulbooking.php

<?php
    $date = $_POST['date'];
    // add code here
?>

Not sure what you want to do with that third page(booking_now.php) too.

Load jQuery with Javascript and use jQuery

Using require.js you can do the same thing in a safer way. You can just define your dependency on jquery and then execute the code you want using the dependency when it is loaded without polluting the namespace:

I generally recommend this library for managing all dependencies on Javascript. It's simple and allows for an efficient optimization of resource loading. However there's some precautions you may need to take when using it with JQuery . My favourite way to deal with them is explained in this github repo and reflected by the following code sample:

<title>jQuery+RequireJS Sample Page</title>
   <script src="scripts/require.js"></script>
   <script>
   require({
       baseUrl: 'scripts',
       paths: {
           jquery: 'https://ajax.googleapis.com/ajax/libs/jquery/1.6.0/jquery.min'
       },
       priority: ['jquery']
    }, ['main']);
    </script>

How to clean project cache in Intellij idea like Eclipse's clean?

In addition to the .Intellij* files, and invalidating the cache, if you really want to clear everything out, then also delete the .idea folder and *.iml per-project files that IntelliJ also generates...

How can I set the initial value of Select2 when using AJAX?

I am adding this answer mainly because I can't comment above! I found it was the comment by @Nicki and her jsfiddle, https://jsfiddle.net/57co6c95/, that eventually got this working for me.

Among other things, it gave examples of the format for the json needed. The only change I had to make was that my initial results were returned in the same format as the other ajax call so I had to use

$option.text(data[0].text).val(data[0].id);

rather than

$option.text(data.text).val(data.id);

How to refresh Android listview?

I was not able to get notifyDataSetChanged() to work on updating my SimpleAdapter, so instead I tried first removing all views that were attached to the parent layout using removeAllViews(), then adding the ListView, and that worked, allowing me to update the UI:

LinearLayout results = (LinearLayout)findViewById(R.id.results);
ListView lv = new ListView(this);
ArrayList<HashMap<String,String>> list = new ArrayList<HashMap<String,String>>();
SimpleAdapter adapter = new SimpleAdapter( this, list, R.layout.directory_row, 
                new String[] { "name", "dept" }, new int[] { R.id.name, R.id.dept } );

for (...) { 
    HashMap<String, String> map = new HashMap<String, String>();
    map.put("name", name);
    map.put("dept", dept);
    list.add(map);
}

lv.setAdapter(adapter);
results.removeAllViews();     
results.addView(lv);

Moment.js - How to convert date string into date?

if you have a string of date, then you should try this.

const FORMAT = "YYYY ddd MMM DD HH:mm";

const theDate = moment("2019 Tue Apr 09 13:30", FORMAT);
// Tue Apr 09 2019 13:30:00 GMT+0300

const theDate1 = moment("2019 Tue Apr 09 13:30", FORMAT).format('LL')
// April 9, 2019

or try this :

const theDate1 = moment("2019 Tue Apr 09 13:30").format(FORMAT);

Convert a JSON String to a HashMap

You can use Jackson API as well for this :

    final String json = "....your json...";
    final ObjectMapper mapper = new ObjectMapper();
    final MapType type = mapper.getTypeFactory().constructMapType(
        Map.class, String.class, Object.class);
    final Map<String, Object> data = mapper.readValue(json, type);

Does a "Find in project..." feature exist in Eclipse IDE?

Open Search Dialog Search-> Search... or use Shortcut Ctrl + H.

  1. Containing text: Type the expression for which you wish to do the text search.
  2. Choose if you want Case sensitive, Regular expression or Whole word
  3. File name patterns: In this field, enter all the file name patterns for the files to find or search through for the specified expression.
  4. Scope: Choose the scope of your search. You can either search the whole workspace, pre-defined working sets, previously selected resources or projects enclosing the selected resources.
  5. Press Search

enter image description here

How do I push to GitHub under a different username?

git add .
git commit -m "initial commit"
git config --local credential.helper ""
git push https://github.com/youraccount/repo.git --all

After this push command, a username password prompt will be opened.

How to make HTML input tag only accept numerical values?

_x000D_
_x000D_
function AllowOnlyNumbers(e) {_x000D_
_x000D_
e = (e) ? e : window.event;_x000D_
var clipboardData = e.clipboardData ? e.clipboardData : window.clipboardData;_x000D_
var key = e.keyCode ? e.keyCode : e.which ? e.which : e.charCode;_x000D_
var str = (e.type && e.type == "paste") ? clipboardData.getData('Text') : String.fromCharCode(key);_x000D_
_x000D_
return (/^\d+$/.test(str));_x000D_
}
_x000D_
<h1>Integer Textbox</h1>_x000D_
    <input type="text" autocomplete="off" id="txtIdNum" onkeypress="return AllowOnlyNumbers(event);" />
_x000D_
_x000D_
_x000D_

JSFiddle: https://jsfiddle.net/ug8pvysc/

What is the difference between UTF-8 and Unicode?

This article explains all the details http://kunststube.net/encoding/

WRITING TO BUFFER

if you write to a 4 byte buffer, symbol ? with UTF8 encoding, your binary will look like this:

00000000 11100011 10000001 10000010

if you write to a 4 byte buffer, symbol ? with UTF16 encoding, your binary will look like this:

00000000 00000000 00110000 01000010

As you can see, depending on what language you would use in your content this will effect your memory accordingly.

e.g. For this particular symbol: ? UTF16 encoding is more efficient since we have 2 spare bytes to use for the next symbol. But it doesn't mean that you must use UTF16 for Japan alphabet.

READING FROM BUFFER

Now if you want to read the above bytes, you have to know in what encoding it was written to and decode it back correctly.

e.g. If you decode this : 00000000 11100011 10000001 10000010 into UTF16 encoding, you will end up with ? not ?

Note: Encoding and Unicode are two different things. Unicode is the big (table) with each symbol mapped to a unique code point. e.g. ? symbol (letter) has a (code point): 30 42 (hex). Encoding on the other hand, is an algorithm that converts symbols to more appropriate way, when storing to hardware.

30 42 (hex) - > UTF8 encoding - > E3 81 82 (hex), which is above result in binary.

30 42 (hex) - > UTF16 encoding - > 30 42 (hex), which is above result in binary.

enter image description here

Attach a body onload event with JS

Why not using jQuery?

$(document).ready(function(){}))

As far as I know, this is the perfect solution.

How to check if any fields in a form are empty in php

Specify POST method in form
<form name="registrationform" action="register.php" method="post">


your form code

</form>

How can I store the result of a system command in a Perl variable?

Try using qx{command} rather than backticks. To me, it's a bit better because: you can do SQL with it and not worry about escaping quotes and such. Depending on the editor and screen, my old eyes tend to miss the tiny back ticks, and it shouldn't ever have an issue with being overloaded like using angle brackets versus glob.

How to call a JavaScript function, declared in <head>, in the body when I want to call it

You can call it like that:

<!DOCTYPE html>
<html lang="en">
    <head>
        <script type="text/javascript">
            var person = { name: 'Joe Blow' };
            function myfunction() {
               document.write(person.name);
            }
        </script>
    </head>
    <body>
        <script type="text/javascript">
            myfunction();
        </script>
    </body>
</html>

The result should be page with the only content: Joe Blow

Look here: http://jsfiddle.net/HWreP/

Best regards!

Is a URL allowed to contain a space?

Can someone point to an RFC indicating that a URL with a space must be encoded?

URIs, and thus URLs, are defined in RFC 3986.

If you look at the grammar defined over there you will eventually note that a space character never can be part of a syntactically legal URL, thus the term "URL with a space" is a contradiction in itself.

How to set space between listView Items in Android

You should wrap your ListView item (say your_listview_item) in some other layout e.g LinearLayout and add margin to your_listview_item:

<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="match_parent">
    <your_listview_item
        android:id="@+id/list_item"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_marginTop="5dp"
        android:layout_marginBottom="5dp"
        android:layout_marginLeft="5dp"
        android:layout_marginRight="5dp"
    ...
    ...
    />
</LinearLayout>

This way you can also add space, if needed, on the right and left of the ListView item.

How to set a value for a selectize.js input?

just ran into the same problem and solved it with the following line of code:

selectize.addOption({text: "My Default Value", value: "My Default Value"});
selectize.setValue("My Default Value"); 

Inline for loop

your list comphresnion will, work but will return list of None because append return None:

demo:

>>> a=[]
>>> [ a.append(x) for x in range(10) ]
[None, None, None, None, None, None, None, None, None, None]
>>> a
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]

better way to use it like this:

>>> a= [ x for x in range(10) ]
>>> a
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]

Python: How to increase/reduce the fontsize of x and y tick labels?

One shouldn't use set_yticklabels to change the fontsize, since this will also set the labels (i.e. it will replace any automatic formatter by a FixedFormatter), which is usually undesired. The easiest is to set the respective tick_params:

ax.tick_params(axis="x", labelsize=8)
ax.tick_params(axis="y", labelsize=20)

or

ax.tick_params(labelsize=8)

in case both axes shall have the same size.

Of course using the rcParams as in @tmdavison's answer is possible as well.

Converting JSON String to Dictionary Not List

pass the data using javascript ajax from get methods

    **//javascript function    
    function addnewcustomer(){ 
    //This function run when button click
    //get the value from input box using getElementById
            var new_cust_name = document.getElementById("new_customer").value;
            var new_cust_cont = document.getElementById("new_contact_number").value;
            var new_cust_email = document.getElementById("new_email").value;
            var new_cust_gender = document.getElementById("new_gender").value;
            var new_cust_cityname = document.getElementById("new_cityname").value;
            var new_cust_pincode = document.getElementById("new_pincode").value;
            var new_cust_state = document.getElementById("new_state").value;
            var new_cust_contry = document.getElementById("new_contry").value;
    //create json or if we know python that is call dictionary.        
    var data = {"cust_name":new_cust_name, "cust_cont":new_cust_cont, "cust_email":new_cust_email, "cust_gender":new_cust_gender, "cust_cityname":new_cust_cityname, "cust_pincode":new_cust_pincode, "cust_state":new_cust_state, "cust_contry":new_cust_contry};
    //apply stringfy method on json
            data = JSON.stringify(data);
    //insert data into database using javascript ajax
            var send_data = new XMLHttpRequest();
            send_data.open("GET", "http://localhost:8000/invoice_system/addnewcustomer/?customerinfo="+data,true);
            send_data.send();

            send_data.onreadystatechange = function(){
              if(send_data.readyState==4 && send_data.status==200){
                alert(send_data.responseText);
              }
            }
          }

django views

    def addNewCustomer(request):
    #if method is get then condition is true and controller check the further line
        if request.method == "GET":
    #this line catch the json from the javascript ajax.
            cust_info = request.GET.get("customerinfo")
    #fill the value in variable which is coming from ajax.
    #it is a json so first we will get the value from using json.loads method.
    #cust_name is a key which is pass by javascript json. 
    #as we know json is a key value pair. the cust_name is a key which pass by javascript json
            cust_name = json.loads(cust_info)['cust_name']
            cust_cont = json.loads(cust_info)['cust_cont']
            cust_email = json.loads(cust_info)['cust_email']
            cust_gender = json.loads(cust_info)['cust_gender']
            cust_cityname = json.loads(cust_info)['cust_cityname']
            cust_pincode = json.loads(cust_info)['cust_pincode']
            cust_state = json.loads(cust_info)['cust_state']
            cust_contry = json.loads(cust_info)['cust_contry']
    #it print the value of cust_name variable on server
            print(cust_name)
            print(cust_cont)
            print(cust_email)
            print(cust_gender)
            print(cust_cityname)
            print(cust_pincode)
            print(cust_state)
            print(cust_contry)
            return HttpResponse("Yes I am reach here.")**

GIT fatal: ambiguous argument 'HEAD': unknown revision or path not in the working tree

I had same issue and I solved it by "pod setup" after installing cocoapods.

How do I set a Windows scheduled task to run in the background?

As noted by Mattias Nordqvist in the comments below, you can also select the radio button option "Run whether user is logged on or not". When saving the task, you will be prompted once for the user password. bambams noted that this wouldn't grant System permissions to the process, and also seems to hide the command window.


It's not an obvious solution, but to make a Scheduled Task run in the background, change the User running the task to "SYSTEM", and nothing will appear on your screen.

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Why is 1/1/1970 the "epoch time"?

History.

The earliest versions of Unix time had a 32-bit integer incrementing at a rate of 60 Hz, which was the rate of the system clock on the hardware of the early Unix systems. The value 60 Hz still appears in some software interfaces as a result. The epoch also differed from the current value. The first edition Unix Programmer's Manual dated November 3, 1971 defines the Unix time as "the time since 00:00:00, Jan. 1, 1971, measured in sixtieths of a second".

IsNullOrEmpty with Object

object MyObject = null;

if (MyObject != null && !string.IsNullOrEmpty(MyObject.ToString())) { ... }

How do I "Add Existing Item" an entire directory structure in Visual Studio?

There is now an open-source extension in the Marketplace that seems to do what the OP was asking for:

Folder To Solution Folder

folder-to-solution-folder

If it doesn't do exactly what you want, the code is available, so you can modify it to suit your scenario.

HTH

Reference alias (calculated in SELECT) in WHERE clause

As a workaround to force the evaluation of the SELECT clause before the WHERE clause, you could put the former in a sub-query while the latter remains in the main query:

SELECT * FROM (
  SELECT (InvoiceTotal - PaymentTotal - CreditTotal) AS BalanceDue
  FROM Invoices) AS temp
WHERE BalanceDue > 0
  

How to export all collections in MongoDB?

There are multiple options depending on what you want to do

1) If you want to export your database to another mongo database, you should use mongodump. This creates a folder of BSON files which have metadata that JSON wouldn't have.

mongodump
mongorestore --host mongodb1.example.net --port 37017 dump/

2) If you want to export your database into JSON you can use mongoexport except you have to do it one collection at a time (this is by design). However I think it's easiest to export the entire database with mongodump and then convert to JSON.

# -d is a valid option for both mongorestore and mongodump

mongodump -d <DATABASE_NAME>
for file in dump/*/*.bson; do bsondump $file > $file.json; done

Display Images Inline via CSS

You have a line break <br> in-between the second and third images in your markup. Get rid of that, and it'll show inline.

How do I write a bash script to restart a process if it dies?

I'm not sure how portable it is across operating systems, but you might check if your system contains the 'run-one' command, i.e. "man run-one". Specifically, this set of commands includes 'run-one-constantly', which seems to be exactly what is needed.

From man page:

run-one-constantly COMMAND [ARGS]

Note: obviously this could be called from within your script, but also it removes the need for having a script at all.

Using find to locate files that match one of multiple patterns

#! /bin/bash
filetypes="*.py *.xml"
for type in $filetypes
do
find Documents -name "$type"
done

simple but works :)

How to make div appear in front of another?

The black div will display the full 500px unless overflow:hidden is set on the 100px li

Microsoft Visual C++ 14.0 is required (Unable to find vcvarsall.bat)

As the other responses pointed out, one solution is to install Visual Studio 2015. However, it takes a few GBs of disk space. One way around is to install precompiled binaries. The webpage http://www.lfd.uci.edu/~gohlke/pythonlibs (mirror) contains precompiled binaries for many Python packages. After downloading the package of interest to you, you can install it using pip install, e.g. pip install mysqlclient-1.3.10-cp35-cp35m-win_amd64.whl.

Fatal error: Out of memory, but I do have plenty of memory (PHP)

this happened to me a few days ago. I did a fresh installation and it still happened. as far as everyone sees and based on your server specs. most likely it is an infinite loop. it could be not on the PHP code itself but on the requests made to Apache.

lets say when you access this url http://localhost/mysite/page_with_multiple_requests

Check your Apache's access log if it receives multiple requests. trace that request and check out the code that might cause a 'bottleneck' to the system (mine's exec() when using sendmail). The bottleneck im talking about doesn't need to be an 'infinite loop'. It could be a function that takes sometime to finish. or maybe some of php's 'program execution functions'

You might need to check ajax requests too (the ones that execute when the page loads). if that ajax request redirects to the same url

e.g. httpx://localhost/mysite/page_with_multiple_requests

it would 'redo' the requests all over again

it would help if you post the random lines or the code itself where the script ends maybe there is a 'loop' code somewhere there. imho php won't just call random lines for nothing.

http://blog.piratelufi.com/2012/08/browser-sending-multiple-requests-at-once/

RecyclerView expand/collapse items

I know it has been a long time since the original question was posted. But i think for slow ones like me a bit of explanation of @Heisenberg's answer would help.

Declare two variable in the adapter class as

private int mExpandedPosition= -1;
private RecyclerView recyclerView = null;

Then in onBindViewHolder following as given in the original answer.

      // This line checks if the item displayed on screen 
      // was expanded or not (Remembering the fact that Recycler View )
      // reuses views so onBindViewHolder will be called for all
      // items visible on screen.
    final boolean isExpanded = position==mExpandedPosition;

        //This line hides or shows the layout in question
        holder.details.setVisibility(isExpanded?View.VISIBLE:View.GONE);

        // I do not know what the heck this is :)
        holder.itemView.setActivated(isExpanded);

        // Click event for each item (itemView is an in-built variable of holder class)
        holder.itemView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

 // if the clicked item is already expaned then return -1 
//else return the position (this works with notifyDatasetchanged )
                mExpandedPosition = isExpanded ? -1:position;
    // fancy animations can skip if like
                TransitionManager.beginDelayedTransition(recyclerView);
    //This will call the onBindViewHolder for all the itemViews on Screen
                notifyDataSetChanged();
            }
        });

And lastly to get the recyclerView object in the adapter override

@Override
public void onAttachedToRecyclerView(@NonNull RecyclerView recyclerView) {
    super.onAttachedToRecyclerView(recyclerView);

    this.recyclerView = recyclerView;
}

Hope this Helps.

HTML5 Local storage vs. Session storage

sessionStorage is the same as localStorage, except that it stores the data for only one session, and it will be removed when the user closes the browser window that created it.

Font Awesome icon inside text input element

<!doctype html>
<html>
  <head>
    ## Heading ##
    <meta charset="utf-8">
      <title>
        Untitled Document
      </title>
      </head>
      <style>
        li {
          display: block;
          width: auto;
        }
        ul li> ul li {
          float: left;
        }
        ul li> ul {
          display: none;
          position: absolute;
        }
        li:hover > ul {
          display: block;
          margin-left: 148px;
          display: inline;
          margin-top: -52px;
        }
        a {
          background: #f2f2ea;
          display: block;
          /*padding:10px 5px;
          */
          width: 186px;
          height: 50px;
          border: solid 2px #c2c2c2;
          border-bottom: none;
          text-decoration: none;
        }
        li:hover >a {
          background: #ffffff;
        }
        ul li>li:hover {
          margin: 12px auto 0px auto;
          padding-top: 10px;
          width: 0;
          height: 0;
          border-top: 8px solid #c2c2c2;
        }
        .bottom {
          border-bottom: solid 2px #c2c2c2;
        }
        .sub_m {
          border-bottom: solid 2px #c2c2c2;
        }
        .sub_m2 {
          border-left: none;
          border-right: none;
          border-bottom: solid 2px #c2c2c2;
        }
        li.selected {
          background: #6D0070;
        }
        #menu_content {
          /*float:left;
          */

        }
        .ca-main {
          padding-top: 18px;
          margin: 0;
          color: #34495e;
          font-size: 18px;
        }
        .ca-sub {
          padding-top: 18px;
          margin: 0px 20px;
          color: #34495e;
          font-size: 18px;
        }
        .submenu a {
          width: auto;
        }
        h2 {
          text-align: center;
        }
      </style>
      <body>
        <ul>
          <li>
            <a href="#">
              <div id="menu_content">
                <h2 class="ca-main">
                  Item 1
                </h2>
              </div>
            </a>
            <ul class="submenu" >
              <li>
                <a href="#" class="sub_m">
                  <div id="menu_content">
                    <h2 class="ca-sub">
                      Item 1_1
                    </h2>
                  </div>
                </a>
              </li>
              <li>

                <a href="#" class="sub_m2">
                  <div id="menu_content">
                    <h2 class="ca-sub">
                      Item 1_2
                    </h2>
                  </div>
                </a>
              </li>
              <li >

                <a href="#" class="sub_m">
                  <div id="menu_content">
                    <h2 class="ca-sub">
                      Item 1_3
                    </h2>
                  </div>
                </a>

              </li>
            </ul>
          </li>
          <li>

            <a href="#">
              <div id="menu_content">
                <h2 class="ca-main">
                  Item 2
                </h2>
              </div>
            </a>
          </li>
          <li>

            <a href="#">
              <div id="menu_content">
                <h2 class="ca-main">
                  Item 3
                </h2>
              </div>
            </a>

          </li>
          <li>

            <a href="#"  class="bottom">
              <div id="menu_content">
                <h2 class="ca-main">
                  Item 4
                </h2>
              </div>
            </a>

          </li>
        </ul>
      </body>
</html>

How to select rows where column value IS NOT NULL using CodeIgniter's ActiveRecord?

One way to check either column is null or not is

$this->db->where('archived => TRUE);
$q = $this->db->get('projects');

in php if column has data, it can be represent as True otherwise False To use multiple comparison in where command and to check if column data is not null do it like

here is the complete example how I am filter columns in where clause (Codeignitor). The last one show Not NULL Compression

$where = array('somebit' => '1', 'status' => 'Published', 'archived ' => TRUE );
$this->db->where($where);

jquery onclick change css background image

Use your jquery like this

$('.home').css({'background-image':'url(images/tabs3.png)'});

How to set the opacity/alpha of a UIImage?

Set the opacity of its view it is showed in.

UIImageView *imageView = [[UIImageView alloc] initWithImage:[UIImage imageWithName:@"SomeName.png"]];
imageView.alpha = 0.5; //Alpha runs from 0.0 to 1.0

Use this in an animation. You can change the alpha in an animation for an duration.

[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:1.0];
//Set alpha
[UIView commitAnimations];

How do I deserialize a complex JSON object in C# .NET?

You could use the nuget package Newtonsoft.JSON in order to achieve this:

JsonConvert.DeserializeObject<List<Response>>(yourJsonString)

How do you get the path to the Laravel Storage folder?

In Laravel 3, call path('storage').

In Laravel 4, use the storage_path() helper function.

Playing m3u8 Files with HTML Video Tag

You can use video js library for easily play HLS video's. It allows to directly play videos

<!-- CSS  -->
 <link href="https://vjs.zencdn.net/7.2.3/video-js.css" rel="stylesheet">


<!-- HTML -->
<video id='hls-example'  class="video-js vjs-default-skin" width="400" height="300" controls>
<source type="application/x-mpegURL" src="http://www.streambox.fr/playlists/test_001/stream.m3u8">
</video>


<!-- JS code -->
<!-- If you'd like to support IE8 (for Video.js versions prior to v7) -->
<script src="https://vjs.zencdn.net/ie8/ie8-version/videojs-ie8.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/videojs-contrib-hls/5.14.1/videojs-contrib-hls.js"></script>
<script src="https://vjs.zencdn.net/7.2.3/video.js"></script>

<script>
var player = videojs('hls-example');
player.play();
</script>

GitHub Video Js

Font Awesome & Unicode

Bear in mind that you may need to include a version number too as you could be using either:

font-family: 'Font Awesome 5 Pro';

or

font-family: 'Font Awesome 5 Free';

How to get all columns' names for all the tables in MySQL?

select * from information_schema.columns
where table_schema = 'your_db'
order by table_name,ordinal_position

Put byte array to JSON and vice versa

In line with @Qwertie's suggestion, but going further on the lazy side, you could just pretend that each byte is a ISO-8859-1 character. For the uninitiated, ISO-8859-1 is a single-byte encoding that matches the first 256 code points of Unicode.

So @Ash's answer is actually redeemable with a charset:

byte[] args2 = getByteArry();
String byteStr = new String(args2, Charset.forName("ISO-8859-1"));

This encoding has the same readability as BAIS, with the advantage that it is processed faster than either BAIS or base64 as less branching is required. It might look like the JSON parser is doing a bit more, but it's fine because dealing with non-ASCII by escaping or by UTF-8 is part of a JSON parser's job anyways. It could map better to some formats like MessagePack with a profile.

Space-wise however, it is usually a loss, as nobody would be using UTF-16 for JSON. With UTF-8 each non-ASCII byte would occupy 2 bytes, while BAIS uses (2+4n + r?(r+1):0) bytes for every run of 3n+r such bytes (r is the remainder).

$lookup on ObjectId's in an array

Starting with MongoDB v3.4 (released in 2016), the $lookup aggregation pipeline stage can also work directly with an array. There is no need for $unwind any more.

This was tracked in SERVER-22881.

Error in Python IOError: [Errno 2] No such file or directory: 'data.csv'

You need to either provide the absolute path to data.csv, or run your script in the same directory as data.csv.

Array length in angularjs returns undefined

use:

$scope.users.length;

Instead of:

$scope.users.lenght;

And next time "spell-check" your code.

Is there a reason for C#'s reuse of the variable in a foreach?

In C# 5.0, this problem is fixed and you can close over loop variables and get the results you expect.

The language specification says:

8.8.4 The foreach statement

(...)

A foreach statement of the form

foreach (V v in x) embedded-statement

is then expanded to:

{
  E e = ((C)(x)).GetEnumerator();
  try {
      while (e.MoveNext()) {
          V v = (V)(T)e.Current;
          embedded-statement
      }
  }
  finally {
      ā€¦ // Dispose e
  }
}

(...)

The placement of v inside the while loop is important for how it is captured by any anonymous function occurring in the embedded-statement. For example:

int[] values = { 7, 9, 13 };
Action f = null;
foreach (var value in values)
{
    if (f == null) f = () => Console.WriteLine("First value: " + value);
}
f();

If v was declared outside of the while loop, it would be shared among all iterations, and its value after the for loop would be the final value, 13, which is what the invocation of f would print. Instead, because each iteration has its own variable v, the one captured by f in the first iteration will continue to hold the value 7, which is what will be printed. (Note: earlier versions of C# declared v outside of the while loop.)

What is pluginManagement in Maven's pom.xml?

So if i understood well, i would say that <pluginManagement> just like <dependencyManagement> are both used to share only the configuration between a parent and it's sub-modules.

For that we define the dependencie's and plugin's common configurations in the parent project and then we only have to declare the dependency/plugin in the sub-modules to use it, without having to define a configuration for it (i.e version or execution, goals, etc). Though this does not prevent us from overriding the configuration in the submodule.

In contrast <dependencies> and <plugins> are inherited along with their configurations and should not be redeclared in the sub-modules, otherwise a conflict would occur.

is that right ?

WPF button click in C# code

You should place below line

btn.Click = btn.Click + btn1_Click;

List vs tuple, when to use each?

Tuples are fixed size in nature whereas lists are dynamic.
In other words, a tuple is immutable whereas a list is mutable.

  1. You can't add elements to a tuple. Tuples have no append or extend method.
  2. You can't remove elements from a tuple. Tuples have no remove or pop method.
  3. You can find elements in a tuple, since this doesnā€™t change the tuple.
  4. You can also use the in operator to check if an element exists in the tuple.

  • Tuples are faster than lists. If you're defining a constant set of values and all you're ever going to do with it is iterate through it, use a tuple instead of a list.

  • It makes your code safer if you ā€œwrite-protectā€ data that does not need to be changed. Using a tuple instead of a list is like having an implied assert statement that this data is constant, and that special thought (and a specific function) is required to override that.

  • Some tuples can be used as dictionary keys (specifically, tuples that contain immutable values like strings, numbers, and other tuples). Lists can never be used as dictionary keys, because lists are not immutable.

Source: Dive into Python 3

HTTP client timeout and server timeout

go to the url about:config and paste each line:

network.http.keep-alive.timeout;10
network.http.connection-retry-timeout;10
network.http.pipelining.read-timeout;5
network.http.connection-timeout;10

What's causing my java.net.SocketException: Connection reset?

This error occurs on the server side when the client closed the socket connection before the response could be returned over the socket. In a web app scenario not all of these are dangerous, since they can be created manually. For example, by quitting the browser before the reponse was retrieved.

Maven is not working in Java 8 when Javadoc tags are incomplete

You could try setting the failOnError property (see plugin documentation) to false:

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-javadoc-plugin</artifactId>
    <version>2.9</version>
    <executions>
        <execution>
            <id>attach-javadocs</id>
            <goals>
                <goal>jar</goal>
            </goals>
            <configuration>
              <failOnError>false</failOnError>
            </configuration>
        </execution>
    </executions>
</plugin>

As you can see from the docs, the default value is true.

Make virtualenv inherit specific packages from your global site-packages

You can use virtualenv --clear. which won't install any packages, then install the ones you want.

How do I disable and re-enable a button in with javascript?

you can try with

document.getElementById('btn').disabled = !this.checked"

_x000D_
_x000D_
<input type="submit" name="btn"  id="btn" value="submit" disabled/>_x000D_
_x000D_
<input type="checkbox"  onchange="document.getElementById('btn').disabled = !this.checked"/>
_x000D_
_x000D_
_x000D_

Using Rsync include and exclude options to include directory and file by pattern

Add -m to the recommended answer above to prune empty directories.

How can I add a background thread to flask?

In addition to using pure threads or the Celery queue (note that flask-celery is no longer required), you could also have a look at flask-apscheduler:

https://github.com/viniciuschiele/flask-apscheduler

A simple example copied from https://github.com/viniciuschiele/flask-apscheduler/blob/master/examples/jobs.py:

from flask import Flask
from flask_apscheduler import APScheduler


class Config(object):
    JOBS = [
        {
            'id': 'job1',
            'func': 'jobs:job1',
            'args': (1, 2),
            'trigger': 'interval',
            'seconds': 10
        }
    ]

    SCHEDULER_API_ENABLED = True


def job1(a, b):
    print(str(a) + ' ' + str(b))

if __name__ == '__main__':
    app = Flask(__name__)
    app.config.from_object(Config())

    scheduler = APScheduler()
    # it is also possible to enable the API directly
    # scheduler.api_enabled = True
    scheduler.init_app(app)
    scheduler.start()

    app.run()

Where is git.exe located?

Using

  • Git 2.11.0,
  • Windows 10,
  • Android studio 2.2

git.exe location:

C:\Users\<.username>\AppData\Local\Programs\Git\cmd\git.exe

Suggestion: while Installing, copy the git path

How can I extract audio from video with ffmpeg?

Seems like you're extracting audio from a video file & downmixing to stereo channel.
To just extract audio (without re-encoding):

ffmpeg.exe -i in.mp4 -vn -c:a copy out.m4a

To extract audio & downmix to stereo (without re-encoding):

ffmpeg.exe -i in.mp4 -vn -c:a copy -ac 2 out.m4a

To generate an mp3 file, you'd re-encode audio:

ffmpeg.exe -i in.mp4 -vn -ac 2 out.mp3

Connect to mysql on Amazon EC2 from a remote server

There could be one of the following reasons:

  1. You need make an entry in the Amazon Security Group to allow remote access from your machine to Amazon EC2 instance. :- I believe this is done by you as from your question it seems like you already made an entry with 0.0.0.0, which allows everybody to access the machine.
  2. MySQL not allowing user to connect from remote machine:- By default MySql creates root user id with admin access. But root id's access is limited to localhost only. This means that root user id with correct password will not work if you try to access MySql from a remote machine. To solve this problem, you need to allow either the root user or some other DB user to access MySQL from remote machine. I would not recommend allowing root user id accessing DB from remote machine. You can use wildcard character % to specify any remote machine.
  3. Check if machine's local firewall is not enabled. And if its enabled then make sure that port 3306 is open.

Please go through following link: How Do I Enable Remote Access To MySQL Database Server?

VBA: Counting rows in a table (list object)

You need to go one level deeper in what you are retrieving.

Dim tbl As ListObject
Set tbl = ActiveSheet.ListObjects("MyTable")
MsgBox tbl.Range.Rows.Count
MsgBox tbl.HeaderRowRange.Rows.Count
MsgBox tbl.DataBodyRange.Rows.Count
Set tbl = Nothing

More information at:

ListObject Interface
ListObject.Range Property
ListObject.DataBodyRange Property
ListObject.HeaderRowRange Property

How to set environment variables in Jenkins?

You can use Environment Injector Plugin to set environment variables in Jenkins at job and node levels. Below I will show how to set them at job level.

  1. From the Jenkins web interface, go to Manage Jenkins > Manage Plugins and install the plugin.

Environment Injector Plugin

  1. Go to your job Configure screen
  2. Find Add build step in Build section and select Inject environment variables
  3. Set the desired environment variable as VARIABLE_NAME=VALUE pattern. In my case, I changed value of USERPROFILE variable

enter image description here

If you need to define a new environment variable depending on some conditions (e.g. job parameters), then you can refer to this answer.

python JSON object must be str, bytes or bytearray, not 'dict

import json
data = json.load(open('/Users/laxmanjeergal/Desktop/json.json'))
jtopy=json.dumps(data) #json.dumps take a dictionary as input and returns a string as output.
dict_json=json.loads(jtopy) # json.loads take a string as input and returns a dictionary as output.
print(dict_json["shipments"])

Awaiting multiple Tasks with different results

Forward Warning

Just a quick headsup to those visiting this and other similar threads looking for a way to parallelize EntityFramework using async+await+task tool-set: The pattern shown here is sound, however, when it comes to the special snowflake of EF you will not achieve parallel execution unless and until you use a separate (new) db-context-instance inside each and every *Async() call involved.

This sort of thing is necessary due to inherent design limitations of ef-db-contexts which forbid running multiple queries in parallel in the same ef-db-context instance.


Capitalizing on the answers already given, this is the way to make sure that you collect all values even in the case that one or more of the tasks results in an exception:

  public async Task<string> Foobar() {
    async Task<string> Awaited(Task<Cat> a, Task<House> b, Task<Tesla> c) {
        return DoSomething(await a, await b, await c);
    }

    using (var carTask = BuyCarAsync())
    using (var catTask = FeedCatAsync())
    using (var houseTask = SellHouseAsync())
    {
        if (carTask.Status == TaskStatus.RanToCompletion //triple
            && catTask.Status == TaskStatus.RanToCompletion //cache
            && houseTask.Status == TaskStatus.RanToCompletion) { //hits
            return Task.FromResult(DoSomething(catTask.Result, carTask.Result, houseTask.Result)); //fast-track
        }

        cat = await catTask;
        car = await carTask;
        house = await houseTask;
        //or Task.AwaitAll(carTask, catTask, houseTask);
        //or await Task.WhenAll(carTask, catTask, houseTask);
        //it depends on how you like exception handling better

        return Awaited(catTask, carTask, houseTask);
   }
 }

An alternative implementation that has more or less the same performance characteristics could be:

 public async Task<string> Foobar() {
    using (var carTask = BuyCarAsync())
    using (var catTask = FeedCatAsync())
    using (var houseTask = SellHouseAsync())
    {
        cat = catTask.Status == TaskStatus.RanToCompletion ? catTask.Result : (await catTask);
        car = carTask.Status == TaskStatus.RanToCompletion ? carTask.Result : (await carTask);
        house = houseTask.Status == TaskStatus.RanToCompletion ? houseTask.Result : (await houseTask);

        return DoSomething(cat, car, house);
     }
 }

How to check if any value is NaN in a Pandas DataFrame

let df be the name of the Pandas DataFrame and any value that is numpy.nan is a null value.

  1. If you want to see which columns has nulls and which do not(just True and False)

    df.isnull().any()
    
  2. If you want to see only the columns that has nulls

    df.loc[:, df.isnull().any()].columns
    
  3. If you want to see the count of nulls in every column

    df.isna().sum()
    
  4. If you want to see the percentage of nulls in every column

    df.isna().sum()/(len(df))*100
    
  5. If you want to see the percentage of nulls in columns only with nulls:

df.loc[:,list(df.loc[:,df.isnull().any()].columns)].isnull().sum()/(len(df))*100

EDIT 1:

If you want to see where your data is missing visually:

import missingno
missingdata_df = df.columns[df.isnull().any()].tolist()
missingno.matrix(df[missingdata_df])

How to launch another aspx web page upon button click?

This button post to the current page while at the same time opens OtherPage.aspx in a new browser window. I think this is what you mean with ...the original page and the newly launched page should both be launched.

<asp:Button ID="myBtn" runat="server" Text="Click me" 
     onclick="myBtn_Click" OnClientClick="window.open('OtherPage.aspx', 'OtherPage');" />

How do we download a blob url video

This is how I manage to "download" it:

  1. Use inspect-element to identify the URL of the M3U playlist file
  2. Download the M3U file
  3. Use VLC to read the M3U file, stream and convert the video to MP4

In Firefox the M3U file appeared as of type application/vnd.apple.mpegurl

enter image description here

The contents of the M3U file would look like:

Open VLC medial player and use the Media => Convert option. Use your (saved) M3U file as the source:

enter image description here

Using "If cell contains" in VBA excel

Private Sub Workbook_SheetChange(ByVal Sh As Object, ByVal Target As Range)

If Not Intersect(Target, Range("C6:ZZ6")) Is Nothing Then

    If InStr(UCase(Target.Value), "TOTAL") > 0 Then
        Target.Offset(1, 0) = "-"
    End If

End If

End Sub

This will allow you to add columns dynamically and automatically insert a dash underneath any columns in the C row after 6 containing case insensitive "Total". Note: If you go past ZZ6, you will need to change the code, but this should get you where you need to go.

React: Expected an assignment or function call and instead saw an expression

Expected an assignment or function call and instead saw an expression.

I had this similar error with this code:

const mapStateToProps = (state) => {
    players: state
}

To correct all I needed to do was add parenthesis around the curved brackets

const mapStateToProps = (state) => ({
    players: state
});

Convert array to string in NodeJS

toString is a method, so you should add parenthesis () to make the function call.

> a = [1,2,3]
[ 1, 2, 3 ]
> a.toString()
'1,2,3'

Besides, if you want to use strings as keys, then you should consider using a Object instead of Array, and use JSON.stringify to return a string.

> var aa = {}
> aa['a'] = 'aaa'
> JSON.stringify(aa)
'{"a":"aaa","b":"bbb"}'

How do I create a batch file timer to execute / call another batch throughout the day

You could also do this>

@echo off
:loop
set a=60
set /a a-1
if a GTR 1 (
echo %a% minutes remaining...
timeout /t 60 /nobreak >nul
goto a
) else if a LSS 1 goto finished
:finished
::code
::code
::code
pause>nul

Or something like that.

How can I make git accept a self signed certificate?

I do it like this:

git init
git config --global http.sslVerify false
git clone https://myurl/myrepo.git

How to build a 'release' APK in Android Studio?

Click \Build\Select Build Variant... in Android Studio. And choose release.

How to debug Apache mod_rewrite

For basic URL resolution, use a command line fetcher like wget or curl to do the testing, rather than a manual browser. Then you don't have to clear any cache; just up arrow and Enter in a shell to re-run your test fetches.

span with onclick event inside a tag

use onmouseup

try something like this

        <html>
        <head>
        <script type="text/javascript">
        function hide(){
        document.getElementById('span_hide').style.display="none";
        }
        </script>
        </head>

        <body>
        <a href="page" style="text-decoration:none;display:block;">
        <span   onmouseup="hide()" id="span_hide">Hide me</span>
        </a>
        </body>
        </html>

EDIT:

          <html>
        <head>
        <script type="text/javascript">
        $(document).ready(function(){
         $("a").click(function () { 
         $(this).fadeTo("fast", .5).removeAttr("href"); 
        });
        });
        function hide(){
        document.getElementById('span_hide').style.display="none";
        }
        </script>
        </head>

        <body>
        <a href="page.html" style="text-decoration:none;display:block;" onclick="return false" >
        <span   onmouseup="hide()" id="span_hide">Hide me</span>
        </a>
        </body>
        </html>

Iframe transparent background

I've used this creating an IFrame through Javascript and it worked for me:

// IFrame points to the IFrame element, obviously
IFrame.src = 'about: blank';
IFrame.style.backgroundColor = "transparent";
IFrame.frameBorder = "0";
IFrame.allowTransparency="true";

Not sure if it makes any difference, but I set those properties before adding the IFrame to the DOM. After adding it to the DOM, I set its src to the real URL.

Print array to a file

However op needs to write array as it is on file I have landed this page to find out a solution where I can write a array to file and than can easily read later using php again.

I have found solution my self by using json_encode so anyone else is looking for the same here is the code:

file_put_contents('array.tmp', json_encode($array));

than read

$array = file_get_contents('array.tmp');
$array = json_decode($array,true);

How to set a timer in android

I used to use (Timer, TimerTask) as well as Handler to kick off (time-consuming) tasks periodically. Now I've switched the whole to RxJava. RxJava provides Observable.timer which is simpler, less error-prone, hassle-free to use.

public class BetterTimerFragment extends Fragment {
  public static final String TAG = "BetterTimer";
  private TextView timeView;
  private Subscription timerSubscription;

  @Override
  public View onCreateView(LayoutInflater inflater,
                           @Nullable ViewGroup container,
                           @Nullable Bundle savedInstanceState) {
    return inflater.inflate(R.layout.fragment_timer, container, false);
  }

  @Override
  public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {
    super.onViewCreated(view, savedInstanceState);
    timeView = (TextView) view.findViewById(R.id.timeView);
  }

  @Override
  public void onResume() {
    super.onResume();

    // Right after the app is visible to users, delay 2 seconds
    // then kick off a (heavy) task every 10 seconds.
    timerSubscription = Observable.timer(2, 10, TimeUnit.SECONDS)
        .map(new Func1<Long, String>() {
          @Override
          public String call(Long unused) {
            // TODO: Probably do time-consuming work here.
            // This runs on a different thread than the main thread.
            return "Time: " + System.currentTimeMillis();
          }
        })
        .observeOn(AndroidSchedulers.mainThread())
        .subscribe(new Action1<String>() {
          @Override
          public void call(String timeText) {
            // The result will then be propagated back to the main thread.
            timeView.setText(timeText);
          }
        }, new Action1<Throwable>() {
          @Override
          public void call(Throwable throwable) {
            Log.e(TAG, throwable.getMessage(), throwable);
          }
        });
  }

  @Override
  public void onPause() {
    super.onPause();

    // Don't kick off tasks when the app gets invisible.
    timerSubscription.unsubscribe();
  }
}

How to make a phone call using intent in Android?

This demo will helpful for you...

On call button click:

Intent intent = new Intent(Intent.ACTION_CALL, Uri.parse("tel:" + "Your Phone_number"));
startActivity(intent);

Permission in Manifest:

 <uses-permission android:name="android.permission.CALL_PHONE" />

Getting coordinates of marker in Google Maps API

var lat = homeMarker.getPosition().lat();
var lng = homeMarker.getPosition().lng();

See the google.maps.LatLng docs and google.maps.Marker getPosition().

How to wait for async method to complete?

The most important thing to know about async and await is that await doesn't wait for the associated call to complete. What await does is to return the result of the operation immediately and synchronously if the operation has already completed or, if it hasn't, to schedule a continuation to execute the remainder of the async method and then to return control to the caller. When the asynchronous operation completes, the scheduled completion will then execute.

The answer to the specific question in your question's title is to block on an async method's return value (which should be of type Task or Task<T>) by calling an appropriate Wait method:

public static async Task<Foo> GetFooAsync()
{
    // Start asynchronous operation(s) and return associated task.
    ...
}

public static Foo CallGetFooAsyncAndWaitOnResult()
{
    var task = GetFooAsync();
    task.Wait(); // Blocks current thread until GetFooAsync task completes
                 // For pedagogical use only: in general, don't do this!
    var result = task.Result;
    return result;
}

In this code snippet, CallGetFooAsyncAndWaitOnResult is a synchronous wrapper around asynchronous method GetFooAsync. However, this pattern is to be avoided for the most part since it will block a whole thread pool thread for the duration of the asynchronous operation. This an inefficient use of the various asynchronous mechanisms exposed by APIs that go to great efforts to provide them.

The answer at "await" doesn't wait for the completion of call has several, more detailed, explanations of these keywords.

Meanwhile, @Stephen Cleary's guidance about async void holds. Other nice explanations for why can be found at http://www.tonicodes.net/blog/why-you-should-almost-never-write-void-asynchronous-methods/ and https://jaylee.org/archive/2012/07/08/c-sharp-async-tips-and-tricks-part-2-async-void.html

How to see log files in MySQL?

The MySQL logs are determined by the global variables such as:

To see the settings and their location, run this shell command:

mysql -se "SHOW VARIABLES" | grep -e log_error -e general_log -e slow_query_log

To print the value of error log, run this command in the terminal:

mysql -e "SELECT @@GLOBAL.log_error"

To read content of the error log file in real time, run:

sudo tail -f $(mysql -Nse "SELECT @@GLOBAL.log_error")

Note: Hit Control-C when finish

When general log is enabled, try:

sudo tail -f $(mysql -Nse "SELECT CONCAT(@@datadir, @@general_log_file)")

To use mysql with the password access, add -p or -pMYPASS parameter. To to keep it remembered, you can configure it in your ~/.my.cnf, e.g.

[client]
user=root
password=root

So it'll be remembered for the next time.

Comparison of DES, Triple DES, AES, blowfish encryption for data

AES is the currently accepted standard algorithm to use (hence the name Advanced Encryption Standard).

The rest are not.

force Maven to copy dependencies into target/lib

If you want to do this on an occasional basis (and thus don't want to change your POM), try this command-line:

mvn dependency:copy-dependencies -DoutputDirectory=${project.build.directory}/lib

If you omit the last argument, the dependences are placed in target/dependencies.

Hex to ascii string conversion

If I understand correctly, you want to know how to convert bytes encoded as a hex string to its form as an ASCII text, like "537461636B" would be converted to "Stack", in such case then the following code should solve your problem.

Have not run any benchmarks but I assume it is not the peak of efficiency.

static char ByteToAscii(const char *input) {
  char singleChar, out;
  memcpy(&singleChar, input, 2);
  sprintf(&out, "%c", (int)strtol(&singleChar, NULL, 16));
  return out;
}

int HexStringToAscii(const char *input, unsigned int length,
                            char **output) {
  int mIndex, sIndex = 0;
  char buffer[length];
  for (mIndex = 0; mIndex < length; mIndex++) {
    sIndex = mIndex * 2;
    char b = ByteToAscii(&input[sIndex]);
    memcpy(&buffer[mIndex], &b, 1);
  }
  *output = strdup(buffer);
  return 0;
}

How to delete specific columns with VBA?

To answer the question How to delete specific columns in vba for excel. I use Array as below.

sub del_col()

dim myarray as variant
dim i as integer

myarray = Array(10, 9, 8)'Descending to Ascending
For i = LBound(myarray) To UBound(myarray)
    ActiveSheet.Columns(myarray(i)).EntireColumn.Delete
Next i

end sub

Is there a command to refresh environment variables from the command prompt in Windows?

You can capture the system environment variables with a vbs script, but you need a bat script to actually change the current environment variables, so this is a combined solution.

Create a file named resetvars.vbs containing this code, and save it on the path:

Set oShell = WScript.CreateObject("WScript.Shell")
filename = oShell.ExpandEnvironmentStrings("%TEMP%\resetvars.bat")
Set objFileSystem = CreateObject("Scripting.fileSystemObject")
Set oFile = objFileSystem.CreateTextFile(filename, TRUE)

set oEnv=oShell.Environment("System")
for each sitem in oEnv 
    oFile.WriteLine("SET " & sitem)
next
path = oEnv("PATH")

set oEnv=oShell.Environment("User")
for each sitem in oEnv 
    oFile.WriteLine("SET " & sitem)
next

path = path & ";" & oEnv("PATH")
oFile.WriteLine("SET PATH=" & path)
oFile.Close

create another file name resetvars.bat containing this code, same location:

@echo off
%~dp0resetvars.vbs
call "%TEMP%\resetvars.bat"

When you want to refresh the environment variables, just run resetvars.bat


Apologetics:

The two main problems I had coming up with this solution were

a. I couldn't find a straightforward way to export environment variables from a vbs script back to the command prompt, and

b. the PATH environment variable is a concatenation of the user and the system PATH variables.

I'm not sure what the general rule is for conflicting variables between user and system, so I elected to make user override system, except in the PATH variable which is handled specifically.

I use the weird vbs+bat+temporary bat mechanism to work around the problem of exporting variables from vbs.

Note: this script does not delete variables.

This can probably be improved.

ADDED

If you need to export the environment from one cmd window to another, use this script (let's call it exportvars.vbs):

Set oShell = WScript.CreateObject("WScript.Shell")
filename = oShell.ExpandEnvironmentStrings("%TEMP%\resetvars.bat")
Set objFileSystem = CreateObject("Scripting.fileSystemObject")
Set oFile = objFileSystem.CreateTextFile(filename, TRUE)

set oEnv=oShell.Environment("Process")
for each sitem in oEnv 
    oFile.WriteLine("SET " & sitem)
next
oFile.Close

Run exportvars.vbs in the window you want to export from, then switch to the window you want to export to, and type:

"%TEMP%\resetvars.bat"

jQuery return ajax result into outside variable

Using 'async': false to prevent asynchronous code is a bad practice,

Synchronous XMLHttpRequest on the main thread is deprecated because of its detrimental effects to the end user's experience. https://xhr.spec.whatwg.org/

On the surface setting async to false fixes a lot of issues because, as the other answers show, you get your data into a variable. However, while waiting for the post data to return (which in some cases could take a few seconds because of database calls, slow connections, etc.) the rest of your Javascript functionality (like triggered events, Javascript handled buttons, JQuery transitions (like accordion, or autocomplete (JQuery UI)) will not be able to occur while the response is pending (which is really bad if the response never comes back as your site is now essentially frozen).

Try this instead,

var return_first;
function callback(response) {
  return_first = response;
  //use return_first variable here
}

$.ajax({
  'type': "POST",
  'global': false,
  'dataType': 'html',
  'url': "ajax.php?first",
  'data': { 'request': "", 'target': arrange_url, 'method': method_target },
  'success': function(data){
       callback(data);
  },
});

How to find serial number of Android device?

Starting in Android 10, apps must have the READ_PRIVILEGED_PHONE_STATE privileged permission in order to access the device's non-resettable identifiers, which include both IMEI and serial number.

Affected methods include the following:

Build getSerial() TelephonyManager getImei() getDeviceId() getMeid() getSimSerialNumber() getSubscriberId()

READ_PRIVILEGED_PHONE_STATE is available for platform only

Sending Windows key using SendKeys

SetForegroundWindow( /* window to gain focus */ );
SendKeys.SendWait("^{ESC}"); // ^{ESC} is code for ctrl + esc which mimics the windows key.

How to load html string in a webview?

You also can try out this

   final WebView webView = new WebView(this);
            webView.loadDataWithBaseURL(null, content, "text/html", "UTF-8", null);

Get last field using awk substr

In this case it is better to use basename instead of awk:

 $ basename /home/parent/child1/child2/filename
 filename

Convert integer to hexadecimal and back again

string HexFromID(int ID)
{
    return ID.ToString("X");
}

int IDFromHex(string HexID)
{
    return int.Parse(HexID, System.Globalization.NumberStyles.HexNumber);
}

I really question the value of this, though. You're stated goal is to make the value shorter, which it will, but that isn't a goal in itself. You really mean either make it easier to remember or easier to type.

If you mean easier to remember, then you're taking a step backwards. We know it's still the same size, just encoded differently. But your users won't know that the letters are restricted to 'A-F', and so the ID will occupy the same conceptual space for them as if the letter 'A-Z' were allowed. So instead of being like memorizing a telephone number, it's more like memorizing a GUID (of equivalent length).

If you mean typing, instead of being able to use the keypad the user now must use the main part of the keyboard. It's likely to be more difficult to type, because it won't be a word their fingers recognize.

A much better option is to actually let them pick a real username.

How to create a List with a dynamic object type

Just use dynamic as the argument:

var list = new List<dynamic>();

Not connecting to SQL Server over VPN

On a default instance, SQL Server listens on TCP/1433 by default. This can be changed. On a named instance, unless configured differently, SQL Server listens on a dynamic TCP port. What that means is should SQL Server discover that the port is in use, it will pick another TCP port. How clients usually find the right port in the case of a named instance is by talking to the SQL Server Listener Service/SQL Browser. That listens on UDP/1434 and cannot be changed. If you have a named instance, you can configure a static port and if you have a need to use Kerberos authentication/delegation, you should.

What you'll need to determine is what port your SQL Server is listening on. Then you'll need to get with your networking/security folks to determine if they allow communication to that port via VPN. If they are, as indicated, check your firewall settings. Some systems have multiple firewalls (my laptop is an example). If so, you'll need to check all the firewalls on your system.

If all of those are correct, verify the server doesn't have an IPSEC policy that restricts access to the SQL Server port via IP address. That also could result in you being blocked.

What is a deadlock?

Lock-based concurrency control

Using locking for controlling access to shared resources is prone to deadlocks, and the transaction scheduler alone cannot prevent their occurrences.

For instance, relational database systems use various locks to guarantee transaction ACID properties.

No matter what relational database system you are using, locks will always be acquired when modifying (e.g., UPDATE or DELETE) a certain table record. Without locking a row that was modified by a currently running transaction, Atomicity would be compromised).

What is a deadlock

A deadlock happens when two concurrent transactions cannot make progress because each one waits for the other to release a lock, as illustrated in the following diagram.

Deadlock

Because both transactions are in the lock acquisition phase, neither one releases a lock prior to acquiring the next one.

Recovering from a deadlock situation

If you're using a Concurrency Control algorithm that relies on locks, then there is always the risk of running into a deadlock situation. Deadlocks can occur in any concurrency environment, not just in a database system.

For instance, a multithreading program can deadlock if two or more threads are waiting on locks that were previously acquired so that no thread can make any progress. If this happens in a Java application, the JVM cannot just force a Thread to stop its execution and release its locks.

Even if the Thread class exposes a stop method, that method has been deprecated since Java 1.1 because it can cause objects to be left in an inconsistent state after a thread is stopped. Instead, Java defines an interrupt method, which acts as a hint as a thread that gets interrupted can simply ignore the interruption and continue its execution.

For this reason, a Java application cannot recover from a deadlock situation, and it is the responsibility of the application developer to order the lock acquisition requests in such a way that deadlocks can never occur.

However, a database system cannot enforce a given lock acquisition order since it's impossible to foresee what other locks a certain transaction will want to acquire further. Preserving the lock order becomes the responsibility of the data access layer, and the database can only assist in recovering from a deadlock situation.

The database engine runs a separate process that scans the current conflict graph for lock-wait cycles (which are caused by deadlocks). When a cycle is detected, the database engine picks one transaction and aborts it, causing its locks to be released, so that the other transaction can make progress.

Unlike the JVM, a database transaction is designed as an atomic unit of work. Hence, a rollback leaves the database in a consistent state.

how to configure apache server to talk to HTTPS backend server?

In my case, my server was configured to work only in https mode, and error occured when I try to access http mode. So changing http://my-service to https://my-service helped.

How to upper case every first letter of word in a string?

    String s = "java is an object oriented programming language.";      
    final StringBuilder result = new StringBuilder(s.length());    
    String words[] = s.split("\\ "); // space found then split it  
    for (int i = 0; i < words.length; i++) 
         {
    if (i > 0){
    result.append(" ");
    }   
    result.append(Character.toUpperCase(words[i].charAt(0))).append(
                words[i].substring(1));   
    }  
    System.out.println(result);  

Output: Java Is An Object Oriented Programming Language.

Calculating text width

I could not get any of the solutions listed to work 100%, so came up with this hybrid, based on ideas from @chmurson (which was in turn based on @Okamera) and also from @philfreo:

(function ($)
{
    var calc;
    $.fn.textWidth = function ()
    {
        // Only create the dummy element once
        calc = calc || $('<span>').css('font', this.css('font')).css({'font-size': this.css('font-size'), display: 'none', 'white-space': 'nowrap' }).appendTo('body');
        var width = calc.html(this.html()).width();
        // Empty out the content until next time - not needed, but cleaner
        calc.empty();
        return width;
    };
})(jQuery);

Notes:

  • this inside a jQuery extension method is already a jQuery object, so no need for all the extra $(this) that many examples have.
  • It only adds the dummy element to the body once, and reuses it.
  • You should also specify white-space: nowrap, just to ensure that it measures it as a single line (and not line wrap based on other page styling).
  • I could not get this to work using font alone and had to explicitly copy font-size as well. Not sure why yet (still investigating).
  • This does not support input fields that way @philfreo does.

In C, how should I read a text file and print all strings

Use "read()" instead o fscanf:

ssize_t read(int fildes, void *buf, size_t nbyte);

DESCRIPTION

The read() function shall attempt to read nbyte bytes from the file associated with the open file descriptor, fildes, into the buffer pointed to by buf.

Here is an example:

http://cmagical.blogspot.com/2010/01/c-programming-on-unix-implementing-cat.html

Working part from that example:

f=open(argv[1],O_RDONLY);
while ((n=read(f,l,80)) > 0)
    write(1,l,n);

An alternate approach is to use getc/putc to read/write 1 char at a time. A lot less efficient. A good example: http://www.eskimo.com/~scs/cclass/notes/sx13.html

Automatically deleting related rows in Laravel (Eloquent ORM)

To elaborate on the selected answer, if your relationships also have child relationships that must be deleted, you have to retrieve all child relationship records first, then call the delete() method so their delete events are fired properly as well.

You can do this easily with higher order messages.

class User extends Eloquent
{
    /**
     * The "booting" method of the model.
     *
     * @return void
     */
    public static function boot() {
        parent::boot();

        static::deleting(function($user) {
             $user->photos()->get()->each->delete();
        });
    }
}

You can also improve performance by querying only the relationships ID column:

class User extends Eloquent
{
    /**
     * The "booting" method of the model.
     *
     * @return void
     */
    public static function boot() {
        parent::boot();

        static::deleting(function($user) {
             $user->photos()->get(['id'])->each->delete();
        });
    }
}

Scrolling an iframe with JavaScript?

I've also had trouble using any type of javascript "scrollTo" function in an iframe on an iPad. Finally found an "old" solution to the problem, just hash to an anchor.

In my situation after an ajax return my error messages were set to display at the top of the iframe but if the user had scrolled down in what is an admittedly long form the submission goes out and the error appears "above the fold". Additionally, assuming the user did scroll way down the top level page was scrolled away from 0,0 and was also hidden.

I added

<a name="ptop"></a>

to the top of my iframe document and

<a name="atop"></a>

to the top of my top level page

then

    $(document).ready(function(){
      $("form").bind("ajax:complete",
        function() {
          location.hash = "#";
          top.location.hash = "#";
          setTimeout('location.hash="#ptop"',150);
          setTimeout('top.location.hash="#atop"',350);
        }
      )
    });

in the iframe.

You have to hash the iframe before the top page or only the iframe will scroll and the top will remain hidden but while it's a tiny bit "jumpy" due to the timeout intervals it works. I imagine tags throughout would allow various "scrollTo" points.

How to connect android emulator to the internet

Make sure Airplane mode is OFF. I kept trying to connect to the internet for a long time before realising what was wrong.

Search for all files in project containing the text 'querystring' in Eclipse

Just noticed that quick search has been included into eclipse 4.13 as a built-in function by typing Ctrl+Alt+Shift+L (or Cmd+Alt+Shift+L on Mac)

https://www.eclipse.org/eclipse/news/4.13/platform.php#quick-text-search

Bootstrap 4: responsive sidebar menu to top navbar

It could be done in Bootstrap 4 using the responsive grid columns. One column for the sidebar and one for the main content.

Bootstrap 4 Sidebar switch to Top Navbar on mobile

<div class="container-fluid h-100">
    <div class="row h-100">
        <aside class="col-12 col-md-2 p-0 bg-dark">
            <nav class="navbar navbar-expand navbar-dark bg-dark flex-md-column flex-row align-items-start">
                <div class="collapse navbar-collapse">
                    <ul class="flex-md-column flex-row navbar-nav w-100 justify-content-between">
                        <li class="nav-item">
                            <a class="nav-link pl-0" href="#">Link</a>
                        </li>
                        ..
                    </ul>
                </div>
            </nav>
        </aside>
        <main class="col">
            ..
        </main>
    </div>
</div>

Alternate sidebar to top
Fixed sidebar to top

For the reverse (Top Navbar that becomes a Sidebar), can be done like this example

Eclipse internal error while initializing Java tooling

Just change the following values at "eclipse.ini" file to the following:

-Xms1024m
-Xmx2048m

Note:

  • You can find the "eclipse.ini" file by right click eclipse icon on and select "Open file location".
  • This error occurs because the eclipse is running out of memory, so we just increased the assigned memory for the eclipse application.

How can I programmatically generate keypress events in C#?

Easily! (because someone else already did the work for us...)

After spending a lot of time trying to this with the suggested answers I came across this codeplex project Windows Input Simulator which made it simple as can be to simulate a key press:

  1. Install the package, can be done or from the NuGet package manager or from the package manager console like:

    Install-Package InputSimulator

  2. Use this 2 lines of code:

    inputSimulator = new InputSimulator() inputSimulator.Keyboard.KeyDown(VirtualKeyCode.RETURN)

And that's it!

-------EDIT--------

The project page on codeplex is flagged for some reason, this is the link to the NuGet gallery.

What do *args and **kwargs mean?

Also, we use them for managing inheritance.

class Super( object ):
   def __init__( self, this, that ):
       self.this = this
       self.that = that

class Sub( Super ):
   def __init__( self, myStuff, *args, **kw ):
       super( Sub, self ).__init__( *args, **kw )
       self.myStuff= myStuff

x= Super( 2.7, 3.1 )
y= Sub( "green", 7, 6 )

This way Sub doesn't really know (or care) what the superclass initialization is. Should you realize that you need to change the superclass, you can fix things without having to sweat the details in each subclass.

Read file from line 2 or skip header row

with open(fname) as f:
    next(f)
    for line in f:
        #do something

Check if element is in the list (contains)

Use std::find, something like:

if (std::find(std::begin(my_list), std::end(my_list), my_var) != std::end(my_list))
    // my_list has my_var

How to set UICollectionViewCell Width and Height programmatically

An other way is to set the value directly in the flow layout

    let layout = collectionView.collectionViewLayout as! UICollectionViewFlowLayout
    layout.itemSize = CGSize(width: size, height: size)

I get conflicting provisioning settings error when I try to archive to submit an iOS app

For those coming from Ionic or Cordova, you can try the following:

Open the file yourproject/platforms/ios/cordova/build-release.xcconfig and change from this:

CODE_SIGN_IDENTITY = iPhone Distribution
CODE_SIGN_IDENTITY[sdk=iphoneos*] = iPhone Distribution

into this:

CODE_SIGN_IDENTITY = iPhone Developer
CODE_SIGN_IDENTITY[sdk=iphoneos*] = iPhone Developer

and try to run the ios cordova build ios --release again to compile a release build.

Reference: https://forum.ionicframework.com/t/ios-build-release-error-is-automatically-signed-for-development-but-a-conflicting-code-signing-identity-iphone-distribution-has-been-manually-specified/100633/7

How to write palindrome in JavaScript

This tests each end of the string going outside in, returning false as soon as a lack of symmetry is detected. For words with an odd number of letters, the center letter is not tested.

function isPalindrome(word){
    var head = 0;
    var tail = word.length - 1;

    while (head < tail) {
        if (word.charAt(head) !== word.charAt(tail)){
            return false
        } else {
            head ++;
            tail --;
        }
    };
    return true;
};

Installing jQuery?

The best thing would be to link to the jQuery core is via google.
There are 3 reasons to do it this way,

  • Decreased Latency
  • Increased parallelism
  • Better caching

      see:
      http://encosia.com/2008/12/10/3-reasons-why-you-should-let-google-host-jquery-for-you/

<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.3.2/jquery.min.js"></script>
<script type="text/javascript">
 $(document).ready(function() {

Your code here.....

  });
</script>

How do you assert that a certain exception is thrown in JUnit 4 tests?

Now that JUnit 5 and JUnit 4.13 have been released, the best option would be to use Assertions.assertThrows() (for JUnit 5) and Assert.assertThrows() (for JUnit 4.13). See the Junit 5 User Guide.

Here is an example that verifies an exception is thrown, and uses Truth to make assertions on the exception message:

public class FooTest {
  @Test
  public void doStuffThrowsIndexOutOfBoundsException() {
    Foo foo = new Foo();

    IndexOutOfBoundsException e = assertThrows(
        IndexOutOfBoundsException.class, foo::doStuff);

    assertThat(e).hasMessageThat().contains("woops!");
  }
}

The advantages over the approaches in the other answers are:

  1. Built into JUnit
  2. You get a useful exception message if the code in the lambda doesn't throw an exception, and a stacktrace if it throws a different exception
  3. Concise
  4. Allows your tests to follow Arrange-Act-Assert
  5. You can precisely indicate what code you are expecting to throw the exception
  6. You don't need to list the expected exception in the throws clause
  7. You can use the assertion framework of your choice to make assertions about the caught exception

A similar method will be added to org.junit Assert in JUnit 4.13.

Autoreload of modules in IPython

REVISED - please see Andrew_1510's answer below, as IPython has been updated.

...

It was a bit hard figure out how to get there from a dusty bug report, but:

It ships with IPython now!

import ipy_autoreload
%autoreload 2
%aimport your_mod

# %autoreload? for help

... then every time you call your_mod.dwim(), it'll pick up the latest version.

WARNING: UNPROTECTED PRIVATE KEY FILE! when trying to SSH into Amazon EC2 Instance

The solution is to make it readable only by the owner of the file, i.e. the last two digits of the octal mode representation should be zero (e.g. mode 0400).

OpenSSH checks this in authfile.c, in a function named sshkey_perm_ok:

/*
 * if a key owned by the user is accessed, then we check the
 * permissions of the file. if the key owned by a different user,
 * then we don't care.
 */
if ((st.st_uid == getuid()) && (st.st_mode & 077) != 0) {
    error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
    error("@         WARNING: UNPROTECTED PRIVATE KEY FILE!          @");
    error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
    error("Permissions 0%3.3o for '%s' are too open.",
        (u_int)st.st_mode & 0777, filename);
    error("It is required that your private key files are NOT accessible by others.");
    error("This private key will be ignored.");
    return SSH_ERR_KEY_BAD_PERMISSIONS;
}

See the first line after the comment: it does a "bitwise and" against the mode of the file, selecting all bits in the last two octal digits (since 07 is octal for 0b111, where each bit stands for r/w/x, respectively).

Closing Twitter Bootstrap Modal From Angular Controller

You can add data-dismiss="modal" to your button attributes which call angularjs funtion.

Such as;

<button type="button" class="btn btn-default" data-dismiss="modal">Send Form</button>

Check box size change with CSS

Try this

<input type="checkbox" style="zoom:1.5;" />
/* The value 1.5 i.e., the size of checkbox will be increased by 0.5% */

Right HTTP status code to wrong input

404 - Not Found - can be used for The URI requested is invalid or the resource requested such as a user, does not exists.

Disable all gcc warnings

-w is the GCC-wide option to disable warning messages.

What does template <unsigned int N> mean?

You templatize your class based on an 'unsigned int'.

Example:

template <unsigned int N>
class MyArray
{
    public:
    private:
        double    data[N]; // Use N as the size of the array
};

int main()
{
    MyArray<2>     a1;
    MyArray<2>     a2;

    MyArray<4>     b1;

    a1 = a2;  // OK The arrays are the same size.
    a1 = b1;  // FAIL because the size of the array is part of the
              //      template and thus the type, a1 and b1 are different types.
              //      Thus this is a COMPILE time failure.
 }

Opacity CSS not working in IE8

You need to set Opacity first for standards-compliant browsers, then the various versions of IE. See Example:

but this opacity code not work in ie8

.slidedownTrigger
{
    cursor: pointer;
    opacity: .75; /* Standards Compliant Browsers */
    filter: alpha(opacity=75); /* IE 7 and Earlier */
    /* Next 2 lines IE8 */
    -ms-filter: "progid:DXImageTransform.Microsoft.Alpha(Opacity=75)";
    filter: progid:DXImageTransform.Microsoft.Alpha(Opacity=75);
}

Note that I eliminated -moz as Firefox is a Standards Compliant browser and that line is no longer necessary. Also, -khtml is depreciated, so I eliminated that style as well.

Furthermore, IE's filters will not validate to w3c standards, so if you want your page to validate, separate your standards stylesheet from your IE stylesheet by using an if IE statement like below:

<!--[if IE]>
<link rel="stylesheet" type="text/css"  href="http://www.mysite.com/css/ie.css" />
<![endif]-->

If you separate the ie quirks, your site will validate just fine.

How to check if my string is equal to null?

if(str.isEmpty() || str==null){ do whatever you want }

Default value of function parameter

On thing to remember here is that the default param must be the last param in the function definition.

Following code will not compile:

void fun(int first, int second = 10, int third);

Following code will compile:

void fun(int first, int second, int third = 10);

How to tell a Mockito mock object to return something different the next time it is called?

You could also Stub Consecutive Calls (#10 in 2.8.9 api). In this case, you would use multiple thenReturn calls or one thenReturn call with multiple parameters (varargs).

import static org.junit.Assert.assertEquals;
import static org.mockito.Mockito.mock;
import static org.mockito.Mockito.when;

import org.junit.Before;
import org.junit.Test;

public class TestClass {

    private Foo mockFoo;

    @Before
    public void setup() {
        setupFoo();
    }

    @Test
    public void testFoo() {
        TestObject testObj = new TestObject(mockFoo);

        assertEquals(0, testObj.bar());
        assertEquals(1, testObj.bar());
        assertEquals(-1, testObj.bar());
        assertEquals(-1, testObj.bar());
    }

    private void setupFoo() {
        mockFoo = mock(Foo.class);

        when(mockFoo.someMethod())
            .thenReturn(0)
            .thenReturn(1)
            .thenReturn(-1); //any subsequent call will return -1

        // Or a bit shorter with varargs:
        when(mockFoo.someMethod())
            .thenReturn(0, 1, -1); //any subsequent call will return -1
    }
}

How do you transfer or export SQL Server 2005 data to Excel

Create the excel data source and insert the values,

insert into OPENROWSET('Microsoft.Jet.OLEDB.4.0', 
'Excel 8.0;Database=D:\testing.xls;', 
'SELECT * FROM [SheetName$]') select * from SQLServerTable

More informations are available here http://www.sqlteam.com/forums/topic.asp?TOPIC_ID=49926

The remote end hung up unexpectedly while git cloning

Wasted a few hours trying some of these solutions but eventually traced this to a corporate IPS (Instrusion Protection System) dropping the connection after a certain amount of data is transferred.

How to convert ActiveRecord results into an array of hashes

May be?

result.map(&:attributes)

If you need symbols keys:

result.map { |r| r.attributes.symbolize_keys }

How do you append to an already existing string?

thank-you Ignacio Vazquez-Abrams

i adapted slightly for better ease of use :)

placed at top of script

NEW_LINE=$'\n'

then to use easily with other variables

variable1="test1"
variable2="test2"

DESCRIPTION="$variable1$NEW_LINE$variable2$NEW_LINE"

OR to append thank-you William Pursell

DESCRIPTION="$variable1$NEW_LINE"
DESCRIPTION+="$variable2$NEW_LINE"

echo "$DESCRIPTION"

Using a cursor with dynamic SQL in a stored procedure

After recently switching from Oracle to SQL Server (employer preference), I notice cursor support in SQL Server is lagging. Cursors are not always evil, sometimes required, sometimes much faster, and sometimes cleaner than trying to tune a complex query by re-arranging or adding optimization hints. The "cursors are evil" opinion is much more prominent in the SQL Server community.

So I guess this answer is to switch to Oracle or give MS a clue.

PHP json_encode encoding numbers as strings

json_encode serializes some data structure in JSON format to be send across the network. Therefore all content will be of the type string. Just like when you receive some parameter from $_POST or $_GET.

If you have to make numeric operations on the values sent, just convert them to int first (with the intval() function in PHP or parseInt() in Javascript) and then execute the operations.

Need to navigate to a folder in command prompt

To access another drive, type the drive's letter, followed by ":".

D:

Then enter:

cd d:\windows\movie

Simple dynamic breadcrumb

Here is a great simple dynamic breadcrumb (tweak as needed):

    <?php 
    $docroot = "/zen/index5.php";
    $path =($_SERVER['REQUEST_URI']);
    $names = explode("/", $path); 
    $trimnames = array_slice($names, 1, -1);
    $length = count($trimnames)-1;
    $fixme = array(".php","-","myname");
    $fixes = array(""," ","My<strong>Name</strong>");
    echo '<div id="breadwrap"><ol id="breadcrumb">';
    $url = "";
    for ($i = 0; $i <= $length;$i++){
    $url .= $trimnames[$i]."/";
        if($i>0 && $i!=$length){
            echo '<li><a href="/'.$url.'">'.ucfirst(str_replace($fixme,$fixes,$trimnames[$i]) . ' ').'</a></li>';
    }
    elseif ($i == $length){
        echo '<li class="current">'.ucfirst(str_replace($fixme,$fixes,$trimnames[$i]) . ' ').'</li>';       
    }
    else{
        echo $trimnames[$i]='<li><a href='.$docroot.' id="bread-home"><span>&nbsp;</span></a></li>';
    }
}
echo '</ol>';
?>

How to hide 'Back' button on navigation bar on iPhone?

In the function viewDidLoad of the UIViewController use the code:

self.navigationItem.hidesBackButton = YES;

Latex - Change margins of only a few pages

Use the "geometry" package and write \newgeometry{left=3cm,bottom=0.1cm} where you want to change your margins. When you want to reset your margins, you write \restoregeometry.

Insert HTML from CSS

No. The only you can do is to add content (and not an element) using :before or :after pseudo-element.

More information: http://www.w3.org/TR/CSS2/generate.html#before-after-content

Specify the from user when sending email using the mail command

Most people need to change two values when trying to correctly forge the from address on an email. First is the from address and the second is the orig-to address. Many of the solutions offered online only change one of these values.

If as root, I try a simple mail command to send myself an email it might look like this. echo "test" | mail -s "a test" [email protected]

And the associated logs: Feb 6 09:02:51 myserver postfix/qmgr[28875]: B10322269D: from=<[email protected]>, size=437, nrcpt=1 (queue active) Feb 6 09:02:52 myserver postfix/smtp[19848]: B10322269D: to=<[email protected]>, relay=myMTA[x.x.x.x]:25, delay=0.34, delays=0.1/0/0.11/0.13, dsn=2.0.0, status=sent (250 Ok 0000014b5f678593-a0e399ef-a801-4655-ad6b-19864a220f38-000000)

Trying to change the from address with -- echo "test" | mail -s "a test" [email protected] -- [email protected]

This changes the orig-to value but not the from value: Feb 6 09:09:09 myserver postfix/qmgr[28875]: 6BD362269D: from=<[email protected]>, size=474, nrcpt=2 (queue active) Feb 6 09:09:09 myserver postfix/smtp[20505]: 6BD362269D: to=<me@noone>, orig_to=<[email protected]>, relay=myMTA[x.x.x.x]:25, delay=0.31, delays=0.06/0/0.09/0.15, dsn=2.0.0, status=sent (250 Ok 0000014b5f6d48e2-a98b70be-fb02-44e0-8eb3-e4f5b1820265-000000)

Next trying it with a -r and a -- to adjust the from and orig-to. echo "test" | mail -s "a test" -r [email protected] [email protected] -- [email protected]

And the logs: Feb 6 09:17:11 myserver postfix/qmgr[28875]: E3B972264C: from=<[email protected]>, size=459, nrcpt=2 (queue active) Feb 6 09:17:11 myserver postfix/smtp[21559]: E3B972264C: to=<[email protected]>, orig_to=<[email protected]>, relay=myMTA[x.x.x.x]:25, delay=1.1, delays=0.56/0.24/0.11/0.17, dsn=2.0.0, status=sent (250 Ok 0000014b5f74a2c0-c06709f0-4e8d-4d7e-9abf-dbcea2bee2ea-000000)

This is how it's working for me. Hope this helps someone.

How to remove hashbang from url?

You'd actually just want to set mode to 'history'.

const router = new VueRouter({
  mode: 'history'
})

Make sure your server is configured to handle these links, though. https://router.vuejs.org/guide/essentials/history-mode.html

Difference between Math.Floor() and Math.Truncate()

Math.Floor(): Returns the largest integer less than or equal to the specified double-precision floating-point number.

Math.Round(): Rounds a value to the nearest integer or to the specified number of fractional digits.

String compare in Perl with "eq" vs "=="

== does a numeric comparison: it converts both arguments to a number and then compares them. As long as $str1 and $str2 both evaluate to 0 as numbers, the condition will be satisfied.

eq does a string comparison: the two arguments must match lexically (case-sensitive) for the condition to be satisfied.

"foo" == "bar";   # True, both strings evaluate to 0.
"foo" eq "bar";   # False, the strings are not equivalent.
"Foo" eq "foo";   # False, the F characters are different cases.
"foo" eq "foo";   # True, both strings match exactly.

Animate the transition between fragments

Here's a slide in/out animation between fragments:

FragmentTransaction transaction = getFragmentManager().beginTransaction();
transaction.setCustomAnimations(R.animator.enter_anim, R.animator.exit_anim);
transaction.replace(R.id.listFragment, new YourFragment());
transaction.commit();

We are using an objectAnimator.

Here are the two xml files in the animator subfolder.

enter_anim.xml

<?xml version="1.0" encoding="utf-8"?>
<set>
     <objectAnimator
         xmlns:android="http://schemas.android.com/apk/res/android"
         android:duration="1000"
         android:propertyName="x"
         android:valueFrom="2000"
         android:valueTo="0"
         android:valueType="floatType" />
</set>

exit_anim.xml

<?xml version="1.0" encoding="utf-8"?>
<set>
    <objectAnimator
        xmlns:android="http://schemas.android.com/apk/res/android"
        android:duration="1000"
        android:propertyName="x"
        android:valueFrom="0"
        android:valueTo="-2000"
        android:valueType="floatType" />
</set>

I hope that would help someone.

Keep a line of text as a single line - wrap the whole line or none at all

You can use white-space: nowrap; to define this behaviour:

// HTML:

_x000D_
_x000D_
.nowrap {_x000D_
  white-space: nowrap ;_x000D_
}
_x000D_
<p>_x000D_
      <span class="nowrap">How do I wrap this line of text</span>_x000D_
      <span class="nowrap">- asked by Peter 2 days ago</span>_x000D_
    </p>
_x000D_
_x000D_
_x000D_

// CSS:
.nowrap {
  white-space: nowrap ;
}

More than 1 row in <Input type="textarea" />

Why not use the <textarea> tag?

?<textarea id="txtArea" rows="10" cols="70"></textarea>

How to convert integer to string in C?

Making your own itoa is also easy, try this :

char* itoa(int i, char b[]){
    char const digit[] = "0123456789";
    char* p = b;
    if(i<0){
        *p++ = '-';
        i *= -1;
    }
    int shifter = i;
    do{ //Move to where representation ends
        ++p;
        shifter = shifter/10;
    }while(shifter);
    *p = '\0';
    do{ //Move back, inserting digits as u go
        *--p = digit[i%10];
        i = i/10;
    }while(i);
    return b;
}

or use the standard sprintf() function.

How can I parse a string with a comma thousand separator to a number?

Yes remove the commas:

parseFloat(yournumber.replace(/,/g, ''));

Check if a class is derived from a generic class

Try this code

static bool IsSubclassOfRawGeneric(Type generic, Type toCheck) {
    while (toCheck != null && toCheck != typeof(object)) {
        var cur = toCheck.IsGenericType ? toCheck.GetGenericTypeDefinition() : toCheck;
        if (generic == cur) {
            return true;
        }
        toCheck = toCheck.BaseType;
    }
    return false;
}

A Generic error occurred in GDI+ in Bitmap.Save method

In my case the bitmap image file already existed in the system drive, so my app threw the error "A Generic error occured in GDI+".

  1. Verify that the destination folder exists
  2. Verify that there isn't already a file with the same name in the destination folder

How do I view events fired on an element in Chrome DevTools?

This won't show custom events like those your script might create if it's a jquery plugin. for example :

jQuery(function($){
 var ThingName="Something";

 $("body a").live('click', function(Event){
   var $this = $(Event.target);
       $this.trigger(ThingName + ":custom-event-one");
 });

 $.on(ThingName + ":custom-event-one", function(Event){
   console.log(ThingName, "Fired Custom Event: 1", Event);
 })

});

The Event Panel under Scripts in chrome developer tools will not show you "Something:custom-event-one"

How do I copy folder with files to another folder in Unix/Linux?

You are looking for the cp command. You need to change directories so that you are outside of the directory you are trying to copy.

If the directory you're copying is called dir1 and you want to copy it to your /home/Pictures folder:

cp -r dir1/ ~/Pictures/

Linux is case-sensitive and also needs the / after each directory to know that it isn't a file. ~ is a special character in the terminal that automatically evaluates to the current user's home directory. If you need to know what directory you are in, use the command pwd.

When you don't know how to use a Linux command, there is a manual page that you can refer to by typing:

man [insert command here]

at a terminal prompt.

Also, to auto complete long file paths when typing in the terminal, you can hit Tab after you've started typing the path and you will either be presented with choices, or it will insert the remaining part of the path.

Can a table have two foreign keys?

CREATE TABLE User (
user_id INT NOT NULL AUTO_INCREMENT,
userName VARCHAR(100) NOT NULL,
password VARCHAR(255) NOT NULL,
email VARCHAR(255) NOT NULL,
userImage  LONGBLOB NOT NULL, 
Favorite VARCHAR(255) NOT NULL,
PRIMARY KEY (user_id)
);

and

CREATE TABLE Event (
    EventID INT NOT NULL AUTO_INCREMENT, 
    PRIMARY KEY (EventID),
    EventName VARCHAR(100) NOT NULL,
    EventLocation VARCHAR(100) NOT NULL,
    EventPriceRange VARCHAR(100) NOT NULL,
    EventDate Date NOT NULL,
    EventTime Time NOT NULL,
    EventDescription VARCHAR(255) NOT NULL,
    EventCategory VARCHAR(255) NOT NULL,
    EventImage  LONGBLOB NOT NULL,     
    index(EventID),
    FOREIGN KEY (EventID) REFERENCES User(user_id)
);

How to allow CORS in react.js?

Possible repeated question from How to overcome the CORS issue in ReactJS

CORS works by adding new HTTP headers that allow servers to describe the set of origins that are permitted to read that information using a web browser. This must be configured in the server to allow cross domain.

You can temporary solve this issue by a chrome plugin called CORS.

Xml Parsing in C#

First add an Enrty and Category class:

public class Entry {     public string Id { get; set; }     public string Title { get; set; }     public string Updated { get; set; }     public string Summary { get; set; }     public string GPoint { get; set; }     public string GElev { get; set; }     public List<string> Categories { get; set; } }  public class Category {     public string Label { get; set; }     public string Term { get; set; } } 

Then use LINQ to XML

XDocument xDoc = XDocument.Load("path");          List<Entry> entries = (from x in xDoc.Descendants("entry")             select new Entry()             {                 Id = (string) x.Element("id"),                 Title = (string)x.Element("title"),                 Updated = (string)x.Element("updated"),                 Summary = (string)x.Element("summary"),                 GPoint = (string)x.Element("georss:point"),                 GElev = (string)x.Element("georss:elev"),                 Categories = (from c in x.Elements("category")                                   select new Category                                   {                                       Label = (string)c.Attribute("label"),                                       Term = (string)c.Attribute("term")                                   }).ToList();             }).ToList(); 

How to unblock with mysqladmin flush hosts

You should put it into command line in windows.

mysqladmin -u [username] -p flush-hosts
**** [MySQL password]

or

mysqladmin flush-hosts -u [username] -p
**** [MySQL password]

For network login use the following command:

mysqladmin -h <RDS ENDPOINT URL> -P <PORT> -u <USER> -p flush-hosts
mysqladmin -h [YOUR RDS END POINT URL] -P 3306 -u [DB USER] -p flush-hosts 

you can permanently solution your problem by editing my.ini file[Mysql configuration file] change variables max_connections = 10000;

or

login into MySQL using command line -

mysql -u [username] -p
**** [MySQL password]

put the below command into MySQL window

SET GLOBAL max_connect_errors=10000;
set global max_connections = 200;

check veritable using command-

show variables like "max_connections";
show variables like "max_connect_errors";

What's the best practice for primary keys in tables?

We do a lot of joins and composite primary keys have just become a performance hog. A simple int or long takes care of many problems even though you are introducing a second candidate key, but it's a lot easier and more understandable to join on one field versus three.

What is the most elegant way to check if all values in a boolean array are true?

In Java 8+, you can create an IntStream in the range of 0 to myArray.length and check that all values are true in the corresponding (primitive) array with something like,

return IntStream.range(0, myArray.length).allMatch(i -> myArray[i]);

StringLength vs MaxLength attributes ASP.NET MVC with Entity Framework EF Code First

MaxLengthAttribute means Max. length of array or string data allowed

StringLengthAttribute means Min. and max. length of characters that are allowed in a data field

Visit http://joeylicc.wordpress.com/2013/06/20/asp-net-mvc-model-validation-using-data-annotations/

Pandas Split Dataframe into two Dataframes at a specific row

I generally use array split because it's easier simple syntax and scales better with more than 2 partitions.

import numpy as np
partitions = 2
dfs = np.array_split(df, partitions)

np.split(df, [100,200,300], axis=0] wants explicit index numbers which may or may not be desirable.

changing color of h2

If you absolutely must use HTML to give your text color, you have to use the (deprecated) <font>-tag:

<h2><font color="#006699">Process Report</font></h2>

But otherwise, I strongly recommend you to do as rekire said: use CSS.

split string in two on given index and return both parts

ES6 1-liner

_x000D_
_x000D_
// :: splitAt = number => Array<any>|string => Array<Array<any>|string>_x000D_
const splitAt = index => x => [x.slice(0, index), x.slice(index)]_x000D_
_x000D_
console.log(_x000D_
  splitAt(1)('foo'), // ["f", "oo"]_x000D_
  splitAt(2)([1, 2, 3, 4]) // [[1, 2], [3, 4]]_x000D_
)_x000D_
  
_x000D_
_x000D_
_x000D_

Execute PHP script in cron job

You may need to run the cron job as a user with permissions to execute the PHP script. Try executing the cron job as root, using the command runuser (man runuser). Or create a system crontable and run the PHP script as an authorized user, as @Philip described.

I provide a detailed answer how to use cron in this stackoverflow post.

How to write a cron that will run a script every day at midnight?

How can I see all the "special" characters permissible in a varchar or char field in SQL Server?

The specific characters that can be stored in a varchar or char column depend upon the column collation. See my answer here for a script that will show you these for the various different collations.

If you want to find all characters outside a particular ASCII range see my answer here.