Programs & Examples On #Nwire

How can I make my website's background transparent without making the content (images & text) transparent too?

Just include following in your code

<body background="C:\Users\Desktop\images.jpg"> 

if you want to specify the size and opacity you can use following

<p><img style="opacity:0.9;" src="C:\Users\Desktop\images.jpg" width="300" height="231" alt="Image" /></p> 

ERROR in ./node_modules/css-loader?

I tried both

npm rebuild node-sass

and

npm install --save node-sass

Later by seeing EACCESS, i checked the folder permission of /node_modules, which was not 777 permission

Then I gave

chmod -R 777 *

-R for recursively(setting the same permission not in the dir but also inside nested sub dir) * is for all files in current directory

What is file permission

To check for permission you can use

ls -l

If u don't know about it, first see here, then check the url

Every file and directory has permission of 'rwx'(read, write, execute). and if 'x' permission is not there, then you can not execture, if no 'w', you can not write into the file. if some thing is missiing it will show in place of r/w/x with '-'. So, if 'x' permission is not there, it will show like 'rw-'

And there will be 3 category of user Owner(who created the file/directory), Group(some people who shares same permission and user previlege), Others(general public)

So 1st letter is 'd'(if it is a directory) or '-'(if it is not a directory), followed by rwx for owner, followed by for group, followed by other

drwxrwxrwx

For example, for 'node_modules'directory I want to give permission to owner all permission and for rest only read, then it will be

drwxr--r--

And about the number assume for 'r/w/x' it is 1 and for '-' it is 0, 777, first 7 is for owner, followed by group, followed by other

Let's assume the permission is rwxr-xrw-

Now 'rwx' is like '111' and it's equivalent decimal is 1*2^2+1*2^1+1*2^0=7

Now 'r-x' is like '101' and it's equivalent decimal is 1*2^2+0*2^1+1*2^0=5

Now 'rw-' is like '110' and it's equivalent decimal is 1*2^2+1*2^1+0*2^0=6

So, it will be 756

How to set a DateTime variable in SQL Server 2008?

Just to explain:

2011-02-15 is being interpreted literally as a mathematical operation, to which the answer is 1994.

This, then, is being interpreted as 1994 days since the origin of date (Jan 1st 1900).

1994 days = 5 years, 6 months, 18 days = June 18th 1905

So, if you don't want to to the calculation each time you want compare a date to a particular value use the standard: Compare the value of the toString() function of date object to the string like this :

set @TEST  ='2011-02-05'

How to execute python file in linux

1.save your file name as hey.py with the below given hello world script

#! /usr/bin/python
print('Hello, world!')

2.open the terminal in that directory

$ python hey.py

or if you are using python3 then

$ python3 hey.py

Excel Macro - Select all cells with data and format as table

Try this one for current selection:

Sub A_SelectAllMakeTable2()
    Dim tbl As ListObject
    Set tbl = ActiveSheet.ListObjects.Add(xlSrcRange, Selection, , xlYes)
    tbl.TableStyle = "TableStyleMedium15"
End Sub

or equivalent of your macro (for Ctrl+Shift+End range selection):

Sub A_SelectAllMakeTable()
    Dim tbl As ListObject
    Dim rng As Range

    Set rng = Range(Range("A1"), Range("A1").SpecialCells(xlLastCell))
    Set tbl = ActiveSheet.ListObjects.Add(xlSrcRange, rng, , xlYes)
    tbl.TableStyle = "TableStyleMedium15"
End Sub

How to export html table to excel using javascript

I try this with jquery; use this and have fun :D

    jQuery.printInExcel = function (DivID) 
{ 
var ExcelApp = new ActiveXObject("Excel.Application"); 
ExcelApp.Workbooks.Add; 
ExcelApp.visible = true; 
var str = ""; 
var tblcount = 0; 
var trcount = 0;
 $("#" + DivID + " table").each(function () 
{ $(this).find("tr").each(function () 
{ var tdcount = 0; $(this).find("td").each(function () 
{ str = str + $(this).text(); ExcelApp.Cells(trcount + 1, tdcount + 1).Value = str; 
str = ""; tdcount++ 
}); 
trcount++ 
}); tblcount++ 
}); 
};

use this in your class and call it with $.printInExcel(your var);

Synchronously waiting for an async operation, and why does Wait() freeze the program here

Calling async code from synchronous code can be quite tricky.

I explain the full reasons for this deadlock on my blog. In short, there's a "context" that is saved by default at the beginning of each await and used to resume the method.

So if this is called in an UI context, when the await completes, the async method tries to re-enter that context to continue executing. Unfortunately, code using Wait (or Result) will block a thread in that context, so the async method cannot complete.

The guidelines to avoid this are:

  1. Use ConfigureAwait(continueOnCapturedContext: false) as much as possible. This enables your async methods to continue executing without having to re-enter the context.
  2. Use async all the way. Use await instead of Result or Wait.

If your method is naturally asynchronous, then you (probably) shouldn't expose a synchronous wrapper.

What is the use of the JavaScript 'bind' method?

Bind Method

A bind implementation might look something like so:

Function.prototype.bind = function () {
  const self = this;
  const args = [...arguments];
  const context = args.shift();

  return function () {
    return self.apply(context, args.concat([...arguments]));
  };
};

The bind function can take any number of arguments and return a new function.

The new function will call the original function using the JS Function.prototype.apply method.
The apply method will use the first argument passed to the target function as its context (this), and the second array argument of the apply method will be a combination of the rest of the arguments from the target function, concat with the arguments used to call the return function (in that order).

An example can look something like so:

_x000D_
_x000D_
function Fruit(emoji) {_x000D_
  this.emoji = emoji;_x000D_
}_x000D_
_x000D_
Fruit.prototype.show = function () {_x000D_
  console.log(this.emoji);_x000D_
};_x000D_
_x000D_
const apple = new Fruit('');_x000D_
const orange = new Fruit('');_x000D_
_x000D_
apple.show();  // _x000D_
orange.show(); // _x000D_
_x000D_
const fruit1 = apple.show;_x000D_
const fruit2 = apple.show.bind();_x000D_
const fruit3 = apple.show.bind(apple);_x000D_
const fruit4 = apple.show.bind(orange);_x000D_
_x000D_
fruit1(); // undefined_x000D_
fruit2(); // undefined_x000D_
fruit3(); // _x000D_
fruit4(); // 
_x000D_
_x000D_
_x000D_

How to add hours to current date in SQL Server?

DATEADD (datepart , number , date )

declare @num_hours int; 
    set @num_hours = 5; 

select dateadd(HOUR, @num_hours, getdate()) as time_added, 
       getdate() as curr_date  

Change priorityQueue to max priorityqueue

You can use lambda expression since Java 8.

The following code will print 10, the larger.

// There is overflow problem when using simple lambda as comparator, as pointed out by ???? ?????.
// PriorityQueue<Integer> pq = new PriorityQueue<>((x, y) -> y - x);

PriorityQueue<Integer> pq =new PriorityQueue<>((x, y) -> Integer.compare(y, x));

pq.add(10);
pq.add(5);
System.out.println(pq.peek());

The lambda function will take two Integers as input parameters, subtract them from each other, and return the arithmetic result. The lambda function implements the Functional Interface, Comparator<T>. (This is used in place, as opposed to an anonymous class or a discrete implementation.)

IsNullOrEmpty with Object

The following code is perfectly fine and the right way (most exact, concise, and clear) to check if an object is null:

object obj = null;

//...

if (obj == null)
{
    // Do something
}

String.IsNullOrEmpty is a method existing for convenience so that you don't have to write the comparison code yourself:

private bool IsNullOrEmpty(string input)
{
    return input == null || input == string.Empty;
}

Additionally, there is a String.IsNullOrWhiteSpace method checking for null and whitespace characters, such as spaces, tabs etc.

How to suppress "unused parameter" warnings in C?

In gcc, you can label the parameter with the unused attribute.

This attribute, attached to a variable, means that the variable is meant to be possibly unused. GCC will not produce a warning for this variable.

In practice this is accomplished by putting __attribute__ ((unused)) just before the parameter. For example:

void foo(workerid_t workerId) { }

becomes

void foo(__attribute__((unused)) workerid_t workerId) { }

Typescript: difference between String and string

TypeScript: String vs string

Argument of type 'String' is not assignable to parameter of type 'string'.

'string' is a primitive, but 'String' is a wrapper object.

Prefer using 'string' when possible.

demo

String Object

// error
class SVGStorageUtils {
  store: object;
  constructor(store: object) {
    this.store = store;
  }
  setData(key: String = ``, data: object) {
    sessionStorage.setItem(key, JSON.stringify(data));
  }
  getData(key: String = ``) {
    const obj = JSON.parse(sessionStorage.getItem(key));
  }
}

string primitive

// ok
class SVGStorageUtils {
  store: object;
  constructor(store: object) {
    this.store = store;
  }
  setData(key: string = ``, data: object) {
    sessionStorage.setItem(key, JSON.stringify(data));
  }
  getData(key: string = ``) {
    const obj = JSON.parse(sessionStorage.getItem(key));
  }
}

enter image description here

Save a subplot in matplotlib

While @Eli is quite correct that there usually isn't much of a need to do it, it is possible. savefig takes a bbox_inches argument that can be used to selectively save only a portion of a figure to an image.

Here's a quick example:

import matplotlib.pyplot as plt
import matplotlib as mpl
import numpy as np

# Make an example plot with two subplots...
fig = plt.figure()
ax1 = fig.add_subplot(2,1,1)
ax1.plot(range(10), 'b-')

ax2 = fig.add_subplot(2,1,2)
ax2.plot(range(20), 'r^')

# Save the full figure...
fig.savefig('full_figure.png')

# Save just the portion _inside_ the second axis's boundaries
extent = ax2.get_window_extent().transformed(fig.dpi_scale_trans.inverted())
fig.savefig('ax2_figure.png', bbox_inches=extent)

# Pad the saved area by 10% in the x-direction and 20% in the y-direction
fig.savefig('ax2_figure_expanded.png', bbox_inches=extent.expanded(1.1, 1.2))

The full figure: Full Example Figure


Area inside the second subplot: Inside second subplot


Area around the second subplot padded by 10% in the x-direction and 20% in the y-direction: Full second subplot

JAX-WS client : what's the correct path to access the local WSDL?

Had the exact same problem that is described herein. No matter what I did, following the above examples, to change the location of my WSDL file (in our case from a web server), it was still referencing the original location embedded within the source tree of the server process.

After MANY hours trying to debug this, I noticed that the Exception was always being thrown from the exact same line (in my case 41). Finally this morning, I decided to just send my source client code to our trade partner so they can at least understand how the code looks, but perhaps build their own. To my shock and horror I found a bunch of class files mixed in with my .java files within my client source tree. How bizarre!! I suspect these were a byproduct of the JAX-WS client builder tool.

Once I zapped those silly .class files and performed a complete clean and rebuild of the client code, everything works perfectly!! Redonculous!!

YMMV, Andrew

PostgreSQL "DESCRIBE TABLE"

In postgres \d is used to describe the table structure.

e.g. \d schema_name.table_name

this command will provide you the basic info of table such as, columns, type and modifiers.

If you want more info about table use

\d+ schema_name.table_name

this will give you extra info such as, storage, stats target and description

Oracle date difference to get number of years

I'd use months_between, possibly combined with floor:

select floor(months_between(date '2012-10-10', date '2011-10-10') /12) from dual;

select floor(months_between(date '2012-10-9' , date '2011-10-10') /12) from dual;

floor makes sure you get down-rounded years. If you want the fractional parts, you obviously want to not use floor.

In plain English, what does "git reset" do?

TL;DR

git reset resets Staging to the last commit. Use --hard to also reset files in your Working directory to the last commit.

LONGER VERSION

But that's obviously simplistic hence the many rather verbose answers. It made more sense for me to read up on git reset in the context of undoing changes. E.g. see this:

If git revert is a “safe” way to undo changes, you can think of git reset as the dangerous method. When you undo with git reset(and the commits are no longer referenced by any ref or the reflog), there is no way to retrieve the original copy—it is a permanent undo. Care must be taken when using this tool, as it’s one of the only Git commands that has the potential to lose your work.

From https://www.atlassian.com/git/tutorials/undoing-changes/git-reset

and this

On the commit-level, resetting is a way to move the tip of a branch to a different commit. This can be used to remove commits from the current branch.

From https://www.atlassian.com/git/tutorials/resetting-checking-out-and-reverting/commit-level-operations

Android Studio don't generate R.java for my import project

Had the same problem and solved it by:

  1. running / building the project (it was deployed to the device, in my case)
  2. right-clicking on the Project/Module/build folder
  3. choose: Synchronize 'build' - then i found

Project/Module/build/source/r/debug/package/R.java

Probably it was even there before the project was build, but I didn't test that.

I hope this was helpful, even though the answer comes a bit late and by now the bug with the

Settings->Compiler->[ ] Use external build

should be fixed afaik ;-)

Logging in Scala

Quick and easy forms.

Scala 2.10 and older:

import com.typesafe.scalalogging.slf4j.Logger
import org.slf4j.LoggerFactory
val logger = Logger(LoggerFactory.getLogger("TheLoggerName"))
logger.debug("Useful message....")

And build.sbt:

libraryDependencies += "com.typesafe" %% "scalalogging-slf4j" % "1.1.0"

Scala 2.11+ and newer:

import import com.typesafe.scalalogging.Logger
import org.slf4j.LoggerFactory
val logger = Logger(LoggerFactory.getLogger("TheLoggerName"))
logger.debug("Useful message....")

And build.sbt:

libraryDependencies += "com.typesafe.scala-logging" %% "scala-logging" % "3.1.0"

Passing an array by reference

It's just the required syntax:

void Func(int (&myArray)[100])

^ Pass array of 100 int by reference the parameters name is myArray;

void Func(int* myArray)

^ Pass an array. Array decays to a pointer. Thus you lose size information.

void Func(int (*myFunc)(double))

^ Pass a function pointer. The function returns an int and takes a double. The parameter name is myFunc.

How to match "any character" in regular expression?

Use the pattern . to match any character once, .* to match any character zero or more times, .+ to match any character one or more times.

Why is pydot unable to find GraphViz's executables in Windows 8?

For windows 8.1 & python 2.7 , I fixed the problem by following below steps

1 . Download and install graphviz-2.38.msi https://graphviz.gitlab.io/_pages/Download/Download_windows.html

2 . Set the path variable

Control Panel > System and Security > System > Advanced System Settings > Environment Variables > Path > Edit add 'C:\Program Files (x86)\Graphviz2.38\bin'

  1. Restart your currently running application that requires the path

How do I perform a Perl substitution on a string while keeping the original?

I hate foo and bar .. who dreamed up these non descriptive terms in programming anyway?

my $oldstring = "replace donotreplace replace donotreplace replace donotreplace";

my $newstring = $oldstring;
$newstring =~ s/replace/newword/g; # inplace replacement

print $newstring;
%: newword donotreplace newword donotreplace newword donotreplace

Moving from JDK 1.7 to JDK 1.8 on Ubuntu

You can easily install 1.8 via PPA. Which can be done by:

$ sudo add-apt-repository ppa:webupd8team/java
$ sudo apt-get update
$ sudo apt-get install oracle-java8-installer

Then check the running version:

$ java -version

If you must do it manually there's already an answer for that on AskUbuntu here.

What requests do browsers' "F5" and "Ctrl + F5" refreshes generate?

When user press F5 although new request goes to web server and get a responce for the request as well. But when the responce header is Parsed it check the required information in browser cache. If the required information in cache has not expired then that information is restored from in cache itself.

When user click on CTRL-F5 even then new request goes to web server and get a responce. But this time when the responce header is Parsed it do not check any required information in cache, and bring all updated information form server only.

CSS Inset Borders

To produce a border inset within an element the only solution I've found (and I've tried all the suggestions in this thread to no avail) is to use a pseudo-element such as :before

E.g.

.has-inset-border:before {
  content: "foo"; /* you need something or it will be invisible at least on Chrome */
  color: transparent;
  position: absolute;
  left: 10px;
  right: 10px;
  top: 10px;
  bottom: 10px;
  border: 4px dashed red;
}

The box-sizing property won't work, as the border always ends up outside everything.

The box-shadow options has the dual disadvantages of not really working and not being supported as widely (and costing more CPU cycles to render, if you care).

Regex to get the words after matching string

Here's a quick Perl script to get what you need. It needs some whitespace chomping.

#!/bin/perl

$sample = <<END;
Subject:
  Security ID:        S-1-5-21-3368353891-1012177287-890106238-22451
  Account Name:       ChamaraKer
  Account Domain:     JIC
  Logon ID:       0x1fffb

Object:
  Object Server:  Security
  Object Type:    File
  Object Name:    D:\\ApacheTomcat\\apache-tomcat-6.0.36\\logs\\localhost.2013- 07-01.log
  Handle ID:  0x11dc
END

my @sample_lines = split /\n/, $sample;
my $path;

foreach my $line (@sample_lines) {
  ($path) = $line =~ m/Object Name:([^s]+)/g;
  if($path) {
    print $path . "\n";
  }
}

Excel VBA - select a dynamic cell range

I like to used this method the most, it will auto select the first column to the last column being used. However, if the last cell in the first row or the last cell in the first column are empty, this code will not calculate properly. Check the link for other methods to dynamically select cell range.

Sub DynamicRange()
'Best used when first column has value on last row and first row has a value in the last column

Dim sht As Worksheet
Dim LastRow As Long
Dim LastColumn As Long
Dim StartCell As Range

Set sht = Worksheets("Sheet1")
Set StartCell = Range("A1")

'Find Last Row and Column
  LastRow = sht.Cells(sht.Rows.Count, StartCell.Column).End(xlUp).Row
  LastColumn = sht.Cells(StartCell.Row, sht.Columns.Count).End(xlToLeft).Column

'Select Range
  sht.Range(StartCell, sht.Cells(LastRow, LastColumn)).Select

End Sub

Remove all values within one list from another list?

>>> a=range(1,10)
>>> for i in [2,3,7]: a.remove(i)
...
>>> a
[1, 4, 5, 6, 8, 9]

>>> a=range(1,10)
>>> b=map(a.remove,[2,3,7])
>>> a
[1, 4, 5, 6, 8, 9]

Is it possible to save HTML page as PDF using JavaScript or jquery?

It is much easier and reliable to convert html to pdf server side. We are using Google Puppeteer. It is well maintained with wrappers for any server side language of your choosing. Puppeteer uses headless Chrome to generate screenshots and/or PDF files. It will save you a LOT of headache especially if you need to generate complex PDF files with tables, images, graphs, multiple pages and so

https://developers.google.com/web/tools/puppeteer/

AngularJS check if form is valid in controller

I have updated the controller to:

.controller('BusinessCtrl',
    function ($scope, $http, $location, Business, BusinessService, UserService, Photo) {
        $scope.$watch('createBusinessForm.$valid', function(newVal) {
            //$scope.valid = newVal;
            $scope.informationStatus = true;
        });
        ...

How to decompile an APK or DEX file on Android platform?

You can decompile an apk on Android device using this : https://play.google.com/store/apps/details?id=com.njlabs.showjava

For more info look here: http://forum.xda-developers.com/showthread.php?t=2601315

EDIT: 28-02-2015

For decompiling an apk you can use this tool: https://apkstudio.codeplex.com/license

If that doesnt help check this link

Java rounding up to an int using Math.ceil

I know this is an old question but in my opinion, we have a better approach which is using BigDecimal to avoid precision loss. By the way, using this solution we have the possibility to use several rounding and scale strategies.

final var dividend = BigDecimal.valueOf(157);
final var divisor = BigDecimal.valueOf(32);
final var result = dividend.divide(divisor, RoundingMode.CEILING).intValue();

Foreign Key to non-primary key

As others have pointed out, ideally, the foreign key would be created as a reference to a primary key (usually an IDENTITY column). However, we don't live in an ideal world, and sometimes even a "small" change to a schema can have significant ripple effects to the application logic.

Consider the case of a Customer table with a SSN column (and a dumb primary key), and a Claim table that also contains a SSN column (populated by business logic from the Customer data, but no FK exists). The design is flawed, but has been in use for several years, and three different applications have been built on the schema. It should be obvious that ripping out Claim.SSN and putting in a real PK-FK relationship would be ideal, but would also be a significant overhaul. On the other hand, putting a UNIQUE constraint on Customer.SSN, and adding a FK on Claim.SSN, could provide referential integrity, with little or no impact on the applications.

Don't get me wrong, I'm all for normalization, but sometimes pragmatism wins over idealism. If a mediocre design can be helped with a band-aid, surgery might be avoided.

How to hide Soft Keyboard when activity starts

If you don't want to use xml, make a Kotlin Extension to hide keyboard

// In onResume, call this
myView.hideKeyboard()

fun View.hideKeyboard() {
    val inputMethodManager = context.getSystemService(INPUT_METHOD_SERVICE) as InputMethodManager
    inputMethodManager.hideSoftInputFromWindow(windowToken, 0)
}

Alternatives based on use case:

fun Fragment.hideKeyboard() {
    view?.let { activity?.hideKeyboard(it) }
}

fun Activity.hideKeyboard() {
    // Calls Context.hideKeyboard
    hideKeyboard(currentFocus ?: View(this))
}

fun Context.hideKeyboard(view: View) {
    view.hideKeyboard()
}

How to show soft keyboard

fun Context.showKeyboard() { // Or View.showKeyboard()
    val inputMethodManager = context.getSystemService(INPUT_METHOD_SERVICE) as InputMethodManager
    inputMethodManager.toggleSoftInput(SHOW_FORCED, HIDE_IMPLICIT_ONLY)
}

Simpler method when simultaneously requesting focus on an edittext

myEdittext.focus()

fun View.focus() {
    requestFocus()
    showKeyboard()
}

Bonus simplification:

Remove requirement for ever using getSystemService: Splitties Library

// Simplifies above solution to just
inputMethodManager.hideSoftInputFromWindow(windowToken, 0)

How do I create a new branch?

Branches in SVN are essentially directories; you don't name the branch so much as choose the name of the directory to branch into.

The common way of 'naming' a branch is to place it under a directory called branches in your repository. In the "To URL:" portion of TortoiseSVN's Branch dialog, you would therefore enter something like:

(svn/http)://path-to-repo/branches/your-branch-name

The main branch of a project is referred to as the trunk, and is usually located in:

(svn/http)://path-to-repo/trunk

PHP: How to get current time in hour:minute:second?

You can combine both in the same date function call

date("d-m-Y H:i:s");  

Android ListView selected item stay highlighted

*please be sure there is no Ripple at your root layout of list view container

add this line to your list view

android:listSelector="@drawable/background_listview"

here is the "background_listview.xml" file

<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:drawable="@color/white_background" android:state_pressed="true" />
<item android:drawable="@color/primary_color" android:state_focused="false" /></selector>

the colors that used in the background_listview.xml file :

<color name="primary_color">#cc7e00</color>
<color name="white_background">#ffffffff</color>

after these

(clicked item contain orange color until you click another item)

Add Auto-Increment ID to existing table?

This SQL request works for me :

ALTER TABLE users
CHANGE COLUMN `id` `id` INT(11) NOT NULL AUTO_INCREMENT ;

MySQL error 1449: The user specified as a definer does not exist

Solution is just a single line query as below :

grant all on *.* to 'ROOT'@'%' identified by 'PASSWORD' with grant option;

Replace ROOT with your mysql user name. Replace PASSWORD with your mysql password.

Java 8 - Best way to transform a list: map or foreach?

If you use Eclipse Collections you can use the collectIf() method.

MutableList<Integer> source =
    Lists.mutable.with(1, null, 2, null, 3, null, 4, null, 5);

MutableList<String> result = source.collectIf(Objects::nonNull, String::valueOf);

Assert.assertEquals(Lists.immutable.with("1", "2", "3", "4", "5"), result);

It evaluates eagerly and should be a bit faster than using a Stream.

Note: I am a committer for Eclipse Collections.

How do I check if a PowerShell module is installed?

Just revisiting this as it's something I just faced and there is some incorrect stuff in the answers (though it's mentioned in the comments).

First thing though. The original questions asks how to tell if a PowerShell module is installed. We need to talk about the word installed! You don't install PowerShell modules (not in the traditional way you install software anyway).

PowerShell modules are either available (i.e. they are on the PowerShell module path), or they are imported (they are imported into your session and you can call the functions contained). This is how to check your module path, in case you want to know where to store a module:

$env:psmodulepath

I'd argue that it's becoming common to use C:\Program Files\WindowsPowerShell\Modules; more often due to it being available to all users, but if you want to lock down your modules to your own session, include them in your profile. C:\Users\%username%\Documents\WindowsPowerShell\Modules;

Alright, back to the two states.

Is the module available (using available to mean installed in the original question)?

Get-Module -Listavailable -Name <modulename>

This tells you if a module is available for import.

Is the module imported? (I'm using this as the answer for the word 'exists' in the original question).

Get-module -Name <modulename>

This will either return an empty load of nothing if the module is not imported, or a one line description of the module if it is. As ever on Stack Overflow, try the commands above on your own modules.

Does the join order matter in SQL?

for regular Joins, it doesn't. TableA join TableB will produce the same execution plan as TableB join TableA (so your C and D examples would be the same)

for left and right joins it does. TableA left Join TableB is different than TableB left Join TableA, BUT its the same than TableB right Join TableA

findViewByID returns null

It crashed for me because one of fields in my activity id was matching with id in an other activity. I fixed it by giving a unique id.

In my loginActivity.xml password field id was "password". In my registration activity I just fixed it by giving id r_password, then it returned not null object:

password = (EditText)findViewById(R.id.r_password);

"Operation must use an updateable query" error in MS Access

set permission on application directory solve this issue with me

To set this permission, right click on the App_Data folder (or whichever other folder you have put the file in) and select Properties. Look for the Security tab. If you can't see it, you need to go to My Computer, then click Tools and choose Folder Options.... then click the View tab. Scroll to the bottom and uncheck "Use simple file sharing (recommended)". Back to the Security tab, you need to add the relevant account to the Group or User Names box. Click Add.... then click Advanced, then Find Now. The appropriate account should be listed. Double click it to add it to the Group or User Names box, then check the Modify option in the permissions. That's it. You are done.

How to select distinct query using symfony2 doctrine query builder?

you could write

select DISTINCT f from t;

as

select f from t group by f;

thing is, I am just currently myself getting into Doctrine, so I cannot give you a real answer. but you could as shown above, simulate a distinct with group by and transform that into Doctrine. if you want add further filtering then use HAVING after group by.

How to define Typescript Map of key value pair. where key is a number and value is an array of objects

The most simple way is to use Record type Record<number, productDetails >

interface productDetails {
   productId : number , 
   price : number , 
   discount : number
};

const myVar : Record<number, productDetails> = {
   1: {
       productId : number , 
       price : number , 
       discount : number
   }
}

Position absolute and overflow hidden

An absolutely positioned element is actually positioned regarding a relative parent, or the nearest found relative parent. So the element with overflow: hidden should be between relative and absolute positioned elements:

<div class="relative-parent">
  <div class="hiding-parent">
    <div class="child"></div>
  </div>
</div>

.relative-parent {
  position:relative;
}
.hiding-parent {
  overflow:hidden;
}
.child {
  position:absolute; 
}

PHP reindex array?

This might not be the simplest answer as compared to using array_values().

Try this

$array = array( 0 => 'string1', 2 => 'string2', 4 => 'string3', 5 => 'string4');
$arrays =$array;
print_r($array);
$array=array();
$i=0;
    foreach($arrays as $k => $item)
    {
    $array[$i]=$item;
        unset($arrays[$k]);
        $i++;

    }

print_r($array);

Demo

How do I use $rootScope in Angular to store variables?

angular.module('myApp').controller('myCtrl', function($scope, $rootScope) {
   var a = //something in the scope
   //put it in the root scope
    $rootScope.test = "TEST";
 });

angular.module('myApp').controller('myCtrl2', function($scope, $rootScope) {
   var b = //get var a from root scope somehow
   //use var b

   $scope.value = $rootScope.test;
   alert($scope.value);

 //    var b = $rootScope.test;
 //  alert(b);
 });

DEMO

Android Studio SDK location

Open the Preferences window by clicking File > Settings (on Mac, Android Studio > Preferences).

In the left panel, click Appearance & Behavior > Android SDK.

You will see the path

How do you return a JSON object from a Java Servlet

response.setContentType("text/json");

//create the JSON string, I suggest using some framework.

String your_string;

out.write(your_string.getBytes("UTF-8"));

How to parse XML to R data frame

Here's a partial solution using xml2. Breaking the solution up into smaller pieces generally makes it easier to ensure everything is lined up:

library(xml2)
data <- read_xml("http://forecast.weather.gov/MapClick.php?lat=29.803&lon=-82.411&FcstType=digitalDWML")

# Point locations
point <- data %>% xml_find_all("//point")
point %>% xml_attr("latitude") %>% as.numeric()
point %>% xml_attr("longitude") %>% as.numeric()

# Start time
data %>% 
  xml_find_all("//start-valid-time") %>% 
  xml_text()

# Temperature
data %>% 
  xml_find_all("//temperature[@type='hourly']/value") %>% 
  xml_text() %>% 
  as.integer()

Bootstrap 3: How do you align column content to bottom of row

Vertical align bottom and remove the float seems to work. I then had a margin issue, but the -2px keeps them from getting pushed down (and they still don't overlap)

.profile-header > div {
  display: inline-block;
  vertical-align: bottom;
  float: none;
  margin: -2px;
}
.profile-header {
  margin-bottom:20px;
  border:2px solid green;
  display: table-cell;
}
.profile-pic {
  height:300px;
  border:2px solid red;
}
.profile-about {
  border:2px solid blue;
}
.profile-about2 {
  border:2px solid pink;
}

Example here: http://www.bootply.com/125740#

What is the difference between using constructor vs getInitialState in React / React Native?

The difference between constructor and getInitialState is the difference between ES6 and ES5 itself.
getInitialState is used with React.createClass and
constructor is used with React.Component.

Hence the question boils down to advantages/disadvantages of using ES6 or ES5.

Let's look at the difference in code

ES5

var TodoApp = React.createClass({ 
  propTypes: {
    title: PropTypes.string.isRequired
  },
  getInitialState () { 
    return {
      items: []
    }; 
  }
});

ES6

class TodoApp extends React.Component {
  constructor () {
    super()
    this.state = {
      items: []
    }
  }
};

There is an interesting reddit thread regarding this.

React community is moving closer to ES6. Also it is considered as the best practice.

There are some differences between React.createClass and React.Component. For instance, how this is handled in these cases. Read more about such differences in this blogpost and facebook's content on autobinding

constructor can also be used to handle such situations. To bind methods to a component instance, it can be pre-bonded in the constructor. This is a good material to do such cool stuff.

Some more good material on best practices
Best Practices for Component State in React.js
Converting React project from ES5 to ES6

Update: April 9, 2019,:

With the new changes in Javascript class API, you don't need a constructor.

You could do

class TodoApp extends React.Component {

    this.state = {items: []}
};

This will still get transpiled to constructor format, but you won't have to worry about it. you can use this format that is more readable.

react hooks image With React Hooks

From React version 16.8, there's a new API Called hooks.

Now, you don't even need a class component to have a state. It can even be done in a functional component.

import React, { useState } from 'react';

function TodoApp () {
  const items = useState([]);

Note that the initial state is passed as an argument to useState; useState([])

Read more about react hooks from the official docs

make bootstrap twitter dialog modal draggable

$("#myModal").draggable({
    handle: ".modal-header"
}); 

it works for me. I got it from there. if you give me thanks please give 70% to Andres Ilich

How can I make one python file run another?

You could use this script:

def run(runfile):
  with open(runfile,"r") as rnf:
    exec(rnf.read())

Syntax:

run("file.py")

memcpy() vs memmove()

C11 standard draft

The C11 N1570 standard draft says:

7.24.2.1 "The memcpy function":

2 The memcpy function copies n characters from the object pointed to by s2 into the object pointed to by s1. If copying takes place between objects that overlap, the behavior is undefined.

7.24.2.2 "The memmove function":

2 The memmove function copies n characters from the object pointed to by s2 into the object pointed to by s1. Copying takes place as if the n characters from the object pointed to by s2 are first copied into a temporary array of n characters that does not overlap the objects pointed to by s1 and s2, and then the n characters from the temporary array are copied into the object pointed to by s1

Therefore, any overlap on memcpy leads to undefined behavior, and anything can happen: bad, nothing or even good. Good is rare though :-)

memmove however clearly says that everything happens as if an intermediate buffer is used, so clearly overlaps are OK.

C++ std::copy is more forgiving however, and allows overlaps: Does std::copy handle overlapping ranges?

Getting the name / key of a JToken with JSON.net

JToken is the base class for JObject, JArray, JProperty, JValue, etc. You can use the Children<T>() method to get a filtered list of a JToken's children that are of a certain type, for example JObject. Each JObject has a collection of JProperty objects, which can be accessed via the Properties() method. For each JProperty, you can get its Name. (Of course you can also get the Value if desired, which is another JToken.)

Putting it all together we have:

JArray array = JArray.Parse(json);

foreach (JObject content in array.Children<JObject>())
{
    foreach (JProperty prop in content.Properties())
    {
        Console.WriteLine(prop.Name);
    }
}

Output:

MobileSiteContent
PageContent

Intercept page exit event

See this article. The feature you are looking for is the onbeforeunload

sample code:

  <script language="JavaScript">
  window.onbeforeunload = confirmExit;
  function confirmExit()
  {
    return "You have attempted to leave this page.  If you have made any changes to the fields without clicking the Save button, your changes will be lost.  Are you sure you want to exit this page?";
  }
</script>

Batch Files - Error Handling

A successful ping on your local network can be trapped using ERRORLEVEL.

@ECHO OFF
PING 10.0.0.123
IF ERRORLEVEL 1 GOTO NOT-THERE
ECHO IP ADDRESS EXISTS
PAUSE
EXIT
:NOT-THERE
ECHO IP ADDRESS NOT NOT EXIST
PAUSE
EXIT

SQL Server Restore Error - Access is Denied

Frnds... I had the same issue while restroring database and tried every solution but could nt get resolved. Then i tried to re install SQL 2005 and the problem solved. Actully last time i forgot to check on customize option while instlling SQL.. It comes two times while installing and i checkd it for ones only..

How to increase heap size of an android application?

Use second process. Declare at AndroidManifest new Service with

android:process=":second"

Exchange between first and second process over BroadcastReceiver

JavaScript: clone a function

I've impoved Jared's answer in my own manner:

    Function.prototype.clone = function() {
        var that = this;
        function newThat() {
            return (new that(
                arguments[0],
                arguments[1],
                arguments[2],
                arguments[3],
                arguments[4],
                arguments[5],
                arguments[6],
                arguments[7],
                arguments[8],
                arguments[9]
            ));
        }
        function __clone__() {
            if (this instanceof __clone__) {
                return newThat.apply(null, arguments);
            }
            return that.apply(this, arguments);
        }
        for(var key in this ) {
            if (this.hasOwnProperty(key)) {
                __clone__[key] = this[key];
            }
        }
        return __clone__;
    };

1) now it supports cloning of constructors (can call with new); in that case takes only 10 arguments (you can vary it) - due to impossibility of passing all arguments in original constructor

2) everything is in correct closures

Razor HtmlHelper Extensions (or other namespaces for views) Not Found

In my case use VS 2013, and It's not support MVC 3 natively (even of you change ./Views/web.config): https://stackoverflow.com/a/28155567/1536197

Regular expression to match a word or its prefix

Use this live online example to test your pattern:

enter image description here

Above screenshot taken from this live example: https://regex101.com/r/cU5lC2/1

Matching any whole word on the commandline.

I'll be using the phpsh interactive shell on Ubuntu 12.10 to demonstrate the PCRE regex engine through the method known as preg_match

Start phpsh, put some content into a variable, match on word.

el@apollo:~/foo$ phpsh

php> $content1 = 'badger'
php> $content2 = '1234'
php> $content3 = '$%^&'

php> echo preg_match('(\w+)', $content1);
1

php> echo preg_match('(\w+)', $content2);
1

php> echo preg_match('(\w+)', $content3);
0

The preg_match method used the PCRE engine within the PHP language to analyze variables: $content1, $content2 and $content3 with the (\w)+ pattern.

$content1 and $content2 contain at least one word, $content3 does not.

Match a specific words on the commandline without word bountaries

el@apollo:~/foo$ phpsh

php> $gun1 = 'dart gun';
php> $gun2 = 'fart gun';
php> $gun3 = 'darty gun';
php> $gun4 = 'unicorn gun';

php> echo preg_match('(dart|fart)', $gun1);
1

php> echo preg_match('(dart|fart)', $gun2);
1

php> echo preg_match('(dart|fart)', $gun3);
1

php> echo preg_match('(dart|fart)', $gun4);
0

Variables gun1 and gun2 contain the string dart or fart which is correct, but gun3 contains darty and still matches, that is the problem. So onto the next example.

Match specific words on the commandline with word boundaries:

Word Boundaries can be force matched with \b, see: Visual analysis of what wordboundary is doing from jex.im/regulex

Regex Visual Image acquired from http://jex.im/regulex and https://github.com/JexCheng/regulex Example:

el@apollo:~/foo$ phpsh

php> $gun1 = 'dart gun';
php> $gun2 = 'fart gun';
php> $gun3 = 'darty gun';
php> $gun4 = 'unicorn gun';

php> echo preg_match('(\bdart\b|\bfart\b)', $gun1);
1

php> echo preg_match('(\bdart\b|\bfart\b)', $gun2);
1

php> echo preg_match('(\bdart\b|\bfart\b)', $gun3);
0

php> echo preg_match('(\bdart\b|\bfart\b)', $gun4);
0

The \b asserts that we have a word boundary, making sure " dart " is matched, but " darty " isn't.

How to detect a loop in a linked list?

I cannot see any way of making this take a fixed amount of time or space, both will increase with the size of the list.

I would make use of an IdentityHashMap (given that there is not yet an IdentityHashSet) and store each Node into the map. Before a node is stored you would call containsKey on it. If the Node already exists you have a cycle.

ItentityHashMap uses == instead of .equals so that you are checking where the object is in memory rather than if it has the same contents.

MD5 hashing in Android

The accepted answer didn't work for me in Android 2.2. I don't know why, but it was "eating" some of my zeros (0) . Apache commons also didn't work on Android 2.2, because it uses methods that are supported only starting from Android 2.3.x. Also, if you want to just MD5 a string, Apache commons is too complex for that. Why one should keep a whole library to use just a small function from it...

Finally I found the following code snippet here which worked perfectly for me. I hope it will be useful for someone...

public String MD5(String md5) {
   try {
        java.security.MessageDigest md = java.security.MessageDigest.getInstance("MD5");
        byte[] array = md.digest(md5.getBytes("UTF-8"));
        StringBuffer sb = new StringBuffer();
        for (int i = 0; i < array.length; ++i) {
          sb.append(Integer.toHexString((array[i] & 0xFF) | 0x100).substring(1,3));
       }
        return sb.toString();
    } catch (java.security.NoSuchAlgorithmException e) {
    } catch(UnsupportedEncodingException ex){
    }
    return null;
}

How to send and receive JSON data from a restful webservice using Jersey API

For me, parameter (JSONObject inputJsonObj) was not working. I am using jersey 2.* Hence I feel this is the

java(Jax-rs) and Angular way

I hope it's helpful to someone using JAVA Rest and AngularJS like me.

@POST
@Consumes(MediaType.TEXT_PLAIN)
@Produces(MediaType.APPLICATION_JSON)
public Map<String, String> methodName(String data) throws Exception {
    JSONObject recoData = new JSONObject(data);
    //Do whatever with json object
}

Client side I used AngularJS

factory.update = function () {
data = {user:'Shreedhar Bhat',address:[{houseNo:105},{city:'Bengaluru'}]};
        data= JSON.stringify(data);//Convert object to string
        var d = $q.defer();
        $http({
            method: 'POST',
            url: 'REST/webApp/update',
            headers: {'Content-Type': 'text/plain'},
            data:data
        })
        .success(function (response) {
            d.resolve(response);
        })
        .error(function (response) {
            d.reject(response);
        });

        return d.promise;
    };

How to read multiple Integer values from a single line of input in Java?

I use it all the time on hackerrank/leetcode

    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    String  lines = br.readLine();    
        
    String[] strs = lines.trim().split("\\s+");
            
    for (int i = 0; i < strs.length; i++) {
    a[i] = Integer.parseInt(strs[i]);
    }

PHP write file from input to txt

use fwrite() instead of file_put_contents()

Can you overload controller methods in ASP.NET MVC?

To overcome this problem you can write an ActionMethodSelectorAttribute that examines the MethodInfo for each action and compares it to the posted Form values and then rejects any method for which the form values don't match (excluding the button name, of course).

Here's an example:- http://blog.abodit.com/2010/02/asp-net-mvc-ambiguous-match/

BUT, this isn't a good idea.

How do I call a dynamically-named method in Javascript?

Within a ServiceWorker or Worker, replace window with self:

self[method_prefix + method_name](arg1, arg2);

Workers have no access to the DOM, therefore window is an invalid reference. The equivalent global scope identifier for this purpose is self.

How can I search an array in VB.NET?

Dim inputString As String = "ra"
Enumerable.Range(0, arr.Length).Where(Function(x) arr(x).ToLower().Contains(inputString.ToLower()))

How to delete all instances of a character in a string in python?

I suggest split (not saying that the other answers are invalid, this is just another way to do it):

def findreplace(char, string):
   return ''.join(string.split(char))

Splitting by a character removes all the characters and turns it into a list. Then we join the list with the join function. You can see the ipython console test below

In[112]: findreplace('i', 'it is icy')
Out[112]: 't s cy'

And the speed...

In[114]: timeit("findreplace('it is icy','i')", "from __main__ import findreplace")
Out[114]: 0.9927914671134204

Not as fast as replace or translate, but ok.

Applying function with multiple arguments to create a new pandas column

If you need to create multiple columns at once:

  1. Create the dataframe:

    import pandas as pd
    df = pd.DataFrame({"A": [10,20,30], "B": [20, 30, 10]})
    
  2. Create the function:

    def fab(row):                                                  
        return row['A'] * row['B'], row['A'] + row['B']
    
  3. Assign the new columns:

    df['newcolumn'], df['newcolumn2'] = zip(*df.apply(fab, axis=1))
    

How can I know when an EditText loses focus?

Implement onFocusChange of setOnFocusChangeListener and there's a boolean parameter for hasFocus. When this is false, you've lost focus to another control.

 EditText txtEdit = (EditText) findViewById(R.id.edittxt);

 txtEdit.setOnFocusChangeListener(new OnFocusChangeListener() {          
        @Override
        public void onFocusChange(View v, boolean hasFocus) {
            if (!hasFocus) {
               // code to execute when EditText loses focus
            }
        }
    });

How to perform a LEFT JOIN in SQL Server between two SELECT statements?

SELECT * FROM 
(SELECT [UserID] FROM [User]) a
LEFT JOIN (SELECT [TailUser], [Weight] FROM [Edge] WHERE [HeadUser] = 5043) b
ON a.UserId = b.TailUser

How does the "this" keyword work?

There is a lot of confusion regarding how "this" keyword is interpreted in JavaScript. Hopefully this article will lay all those to rest once and for all. And a lot more. Please read the entire article carefully. Be forewarned that this article is long.

Irrespective of the context in which it is used, "this" always references the "current object" in Javascript. However, what the "current object" is differs according to context. The context may be exactly 1 of the 6 following:

  1. Global (i.e. Outside all functions)
  2. Inside Direct "Non Bound Function" Call (i.e. a function that has not been bound by calling functionName.bind)
  3. Inside Indirect "Non Bound Function" Call through functionName.call and functionName.apply
  4. Inside "Bound Function" Call (i.e. a function that has been bound by calling functionName.bind)
  5. While Object Creation through "new"
  6. Inside Inline DOM event handler

The following describes each of this contexts one by one:

  1. Global Context (i.e. Outside all functions):

    Outside all functions (i.e. in global context) the "current object" (and hence the value of "this") is always the "window" object for browsers.

  2. Inside Direct "Non Bound Function" Call:

    Inside a Direct "Non Bound Function" Call, the object that invoked the function call becomes the "current object" (and hence the value of "this"). If a function is called without a explicit current object, the current object is either the "window" object (For Non Strict Mode) or undefined (For Strict Mode) . Any function (or variable) defined in Global Context automatically becomes a property of the "window" object.For e.g Suppose function is defined in Global Context as

    function UserDefinedFunction(){
        alert(this)
        }
    

    it becomes the property of the window object, as if you have defined it as

    window.UserDefinedFunction=function(){
      alert(this)
    }  
    

    In "Non Strict Mode", Calling/Invoking this function directly through "UserDefinedFunction()" will automatically call/invoke it as "window.UserDefinedFunction()" making "window" as the "current object" (and hence the value of "this") within "UserDefinedFunction".Invoking this function in "Non Strict Mode" will result in the following

    UserDefinedFunction() // displays [object Window]  as it automatically gets invoked as window.UserDefinedFunction()
    

    In "Strict Mode", Calling/Invoking the function directly through "UserDefinedFunction()" will "NOT" automatically call/invoke it as "window.UserDefinedFunction()".Hence the "current object" (and the value of "this") within "UserDefinedFunction" shall be undefined. Invoking this function in "Strict Mode" will result in the following

    UserDefinedFunction() // displays undefined
    

    However, invoking it explicitly using window object shall result in the following

    window.UserDefinedFunction() // "always displays [object Window]   irrespective of mode."
    

    Let us look at another example. Please look at the following code

     function UserDefinedFunction()
        {
            alert(this.a + ","  + this.b + ","  + this.c  + ","  + this.d)
        }
    
    var o1={
                a:1,
                b:2,
                f:UserDefinedFunction
          }
    var o2={
                c:3,
                d:4,
                f:UserDefinedFunction
           }
    
    o1.f() // Shall display 1,2,undefined,undefined
    o2.f() // Shall display undefined,undefined,3,4
    

    In the above example we see that when "UserDefinedFunction" was invoked through o1, "this" takes value of o1 and the value of its properties "a" and "b" get displayed. The value of "c" and "d" were shown as undefined as o1 does not define these properties

    Similarly when "UserDefinedFunction" was invoked through o2, "this" takes value of o2 and the value of its properties "c" and "d" get displayed.The value of "a" and "b" were shown as undefined as o2 does not define these properties.

  3. Inside Indirect "Non Bound Function" Call through functionName.call and functionName.apply:

    When a "Non Bound Function" is called through functionName.call or functionName.apply, the "current object" (and hence the value of "this") is set to the value of "this" parameter (first parameter) passed to call/apply. The following code demonstrates the same.

    function UserDefinedFunction()
    {
        alert(this.a + ","  + this.b + ","  + this.c  + ","  + this.d)
    }
    var o1={
                a:1,
                b:2,
                f:UserDefinedFunction
           }
    var o2={
                c:3,
                d:4,
                f:UserDefinedFunction
           }
    
    UserDefinedFunction.call(o1) // Shall display 1,2,undefined,undefined
    UserDefinedFunction.apply(o1) // Shall display 1,2,undefined,undefined
    
    UserDefinedFunction.call(o2) // Shall display undefined,undefined,3,4
    UserDefinedFunction.apply(o2) // Shall display undefined,undefined,3,4
    
    o1.f.call(o2) // Shall display undefined,undefined,3,4
    o1.f.apply(o2) // Shall display undefined,undefined,3,4
    
    o2.f.call(o1) // Shall display 1,2,undefined,undefined
    o2.f.apply(o1) // Shall display 1,2,undefined,undefined
    

    The above code clearly shows that the "this" value for any "NON Bound Function" can be altered through call/apply. Also,if the "this" parameter is not explicitly passed to call/apply, "current object" (and hence the value of "this") is set to "window" in Non strict mode and "undefined" in strict mode.

  4. Inside "Bound Function" Call (i.e. a function that has been bound by calling functionName.bind):

    A bound function is a function whose "this" value has been fixed. The following code demonstrated how "this" works in case of bound function

    function UserDefinedFunction()
    {
        alert(this.a + ","  + this.b + ","  + this.c  + ","  + this.d)
    }
    var o1={
              a:1,
              b:2,
              f:UserDefinedFunction,
              bf:null
           }
    var o2={
               c:3,
               d:4,
               f:UserDefinedFunction,
               bf:null
            }
    
    var bound1=UserDefinedFunction.bind(o1); // permanantly fixes "this" value of function "bound1" to Object o1
    bound1() // Shall display 1,2,undefined,undefined
    
    var bound2=UserDefinedFunction.bind(o2); // permanantly fixes "this" value of function "bound2" to Object o2
    bound2() // Shall display undefined,undefined,3,4
    
    var bound3=o1.f.bind(o2); // permanantly fixes "this" value of function "bound3" to Object o2
    bound3() // Shall display undefined,undefined,3,4
    
    var bound4=o2.f.bind(o1); // permanantly fixes "this" value of function "bound4" to Object o1
    bound4() // Shall display 1,2,undefined,undefined
    
    o1.bf=UserDefinedFunction.bind(o2) // permanantly fixes "this" value of function "o1.bf" to Object o2
    o1.bf() // Shall display undefined,undefined,3,4
    
    o2.bf=UserDefinedFunction.bind(o1) // permanantly fixes "this" value of function "o2.bf" to Object o1
    o2.bf() // Shall display 1,2,undefined,undefined
    
    bound1.call(o2) // Shall still display 1,2,undefined,undefined. "call" cannot alter the value of "this" for bound function
    
    bound1.apply(o2) // Shall still display 1,2,undefined,undefined. "apply" cannot alter the value of "this" for bound function
    
    o2.bf.call(o2) // Shall still display 1,2,undefined,undefined. "call" cannot alter the value of "this" for bound function
    o2.bf.apply(o2) // Shall still display 1,2,undefined,undefined."apply" cannot alter the value of "this" for bound function
    

    As given in the code above, "this" value for any "Bound Function" CANNOT be altered through call/apply. Also, if the "this" parameter is not explicitly passed to bind, "current object" (and hence the value of "this" ) is set to "window" in Non strict mode and "undefined" in strict mode. One more thing. Binding an already bound function does not change the value of "this". It remains set as the value set by first bind function.

  5. While Object Creation through "new":

    Inside a constructor function, the "current object" (and hence the value of "this") references the object that is currently being created through "new" irrespective of the bind status of the function. However if the constructor is a bound function it shall get called with predefined set of arguments as set for the bound function.

  6. Inside Inline DOM event handler:

    Please look at the following HTML Snippet

    <button onclick='this.style.color=white'>Hello World</button>
    <div style='width:100px;height:100px;' onclick='OnDivClick(event,this)'>Hello World</div>
    

    The "this" in above examples refer to "button" element and the "div" element respectively.

    In the first example, the font color of the button shall be set to white when it is clicked.

    In the second example when the "div" element is clicked it shall call the OnDivClick function with its second parameter referencing the clicked div element. However the value of "this" within OnDivClick SHALL NOT reference the clicked div element. It shall be set as the "window object" or "undefined" in Non strict and Strict Modes respectively (if OnDivClick is an unbound function) or set to a predefined Bound value (if OnDivClick is a bound function)

The following summarizes the entire article

  1. In Global Context "this" always refers to the "window" object

  2. Whenever a function is invoked, it is invoked in context of an object ("current object"). If the current object is not explicitly provided, the current object is the "window object" in NON Strict Mode and "undefined" in Strict Mode by default.

  3. The value of "this" within a Non Bound function is the reference to object in context of which the function is invoked ("current object")

  4. The value of "this" within a Non Bound function can be overriden by call and apply methods of the function.

  5. The value of "this" is fixed for a Bound function and cannot be overriden by call and apply methods of the function.

  6. Binding and already bound function does not change the value of "this". It remains set as the value set by first bind function.

  7. The value of "this" within a constructor is the object that is being created and initialized

  8. The value of "this" within an inline DOM event handler is reference to the element for which the event handler is given.

How to open maximized window with Javascript?

 window.open('your_url', 'popup_name','height=' + screen.height + ',width=' + screen.width + ',resizable=yes,scrollbars=yes,toolbar=yes,menubar=yes,location=yes')

tsql returning a table from a function or store procedure

Use this as a template

SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
-- =============================================
-- Author:      <Author,,Name>
-- Create date: <Create Date,,>
-- Description: <Description,,>
-- =============================================
CREATE FUNCTION <Table_Function_Name, sysname, FunctionName> 
(
    -- Add the parameters for the function here
    <@param1, sysname, @p1> <data_type_for_param1, , int>, 
    <@param2, sysname, @p2> <data_type_for_param2, , char>
)
RETURNS 
<@Table_Variable_Name, sysname, @Table_Var> TABLE 
(
    -- Add the column definitions for the TABLE variable here
    <Column_1, sysname, c1> <Data_Type_For_Column1, , int>, 
    <Column_2, sysname, c2> <Data_Type_For_Column2, , int>
)
AS
BEGIN
    -- Fill the table variable with the rows for your result set

    RETURN 
END
GO

That will define your function. Then you would just use it as any other table:

Select * from MyFunction(Param1, Param2, etc.)

spark submit add multiple jars in classpath

You can use * for import all jars into a folder when adding in conf/spark-defaults.conf .

spark.driver.extraClassPath /fullpath/*
spark.executor.extraClassPath /fullpath/*

How to import Google Web Font in CSS file?

Along with the above answers, do also consider this site; https://google-webfonts-helper.herokuapp.com/fonts

Advantage:

  • allows you to self-host those google fonts for better response times

  • choose your font(s)

  • choose your character set
  • choose your font styles/weight
  • choose your target browser
  • and u get the CSS snippets ( add to your css stylesheet ) plus a zip of the font files to include in your project

E.g your_theme.css

@font-face { 
    font-family: 'Open Sans'; 
    font-style: normal;  
    font-weight: 400;
    src: local('Open Sans Regular'), local('OpenSans-Regular'),
             url('css_fonts/open-sans-v15-latin-regular.woff2') format('woff2'), 
             url('css_fonts/open-sans-v15-latin-regular.woff') format('woff'); 
}

body { 
    font-family: 'Open Sans',sans-serif;
}

How to change btn color in Bootstrap

The simplest way is to:

  1. intercept every button state

  2. add !important to override the states

    .btn-primary:hover,
    .btn-primary:active,
    .btn-primary:visited,
    .btn-primary:focus {
      background-color: black !important;
      border-color: black !important;
    }

OR the more practical UI way is to make the hover state of the button darker than the original state. Just use the CSS snippet below:

.btn-primary {
  background-color: Blue !important;
  border-color: Blue !important;
}
.btn-primary:hover,
.btn-primary:active,
.btn-primary:visited,
.btn-primary:focus {
  background-color: DarkBlue !important;
  border-color: DarkBlue !important;
}

Maximum number of threads in a .NET app?

i did a test on a 64bit system with c# console, the exception is type of out of memory, using 2949 threads.

I realize we should be using threading pool, which I do, but this answer is in response to the main question ;)

How to start http-server locally

When you're running npm install in the project's root, it installs all of the npm dependencies into the project's node_modules directory.

If you take a look at the project's node_modules directory, you should see a directory called http-server, which holds the http-server package, and a .bin folder, which holds the executable binaries from the installed dependencies. The .bin directory should have the http-server binary (or a link to it).

So in your case, you should be able to start the http-server by running the following from your project's root directory (instead of npm start):

./node_modules/.bin/http-server -a localhost -p 8000 -c-1

This should have the same effect as running npm start.

If you're running a Bash shell, you can simplify this by adding the ./node_modules/.bin folder to your $PATH environment variable:

export PATH=./node_modules/.bin:$PATH

This will put this folder on your path, and you should be able to simply run

http-server -a localhost -p 8000 -c-1

Update UI from Thread in Android

If you use Handler (I see you do and hopefully you created its instance on the UI thread), then don't use runOnUiThread() inside of your runnable. runOnUiThread() is used when you do smth from a non-UI thread, however Handler will already execute your runnable on UI thread.

Try to do smth like this:

private Handler mHandler = new Handler();
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.gameone);
    res = getResources();
    // pB.setProgressDrawable(getResources().getDrawable(R.drawable.green)); **//Works**
    mHandler.postDelayed(runnable, 1);
}

private Runnable runnable = new Runnable() {
    public void run() {
        pB.setProgressDrawable(getResources().getDrawable(R.drawable.green));
        pB.invalidate(); // maybe this will even not needed - try to comment out
    }
};

Coerce multiple columns to factors at once

Here is a data.table example. I used grep in this example because that's how I often select many columns by using partial matches to their names.

library(data.table)
data <- data.table(matrix(sample(1:40), 4, 10, dimnames = list(1:4, LETTERS[1:10])))

factorCols <- grep(pattern = "A|C|D|H", x = names(data), value = TRUE)

data[, (factorCols) := lapply(.SD, as.factor), .SDcols = factorCols]

What is the naming convention in Python for variable and function names?

Typically, one follow the conventions used in the language's standard library.

How to export table as CSV with headings on Postgresql?

This works

psql dbname -F , --no-align -c "SELECT * FROM TABLE"

trigger click event from angularjs directive

Here is perhaps a different way for you to achieve this. Pass into the directive both the index and the item and let the directive setup the html in a template:

Demo: http://plnkr.co/edit/ybcNosdPA76J1IqXjcGG?p=preview

html:

<ul id="thumbnails">
    <li class="thumbnail" ng-repeat="item in items" options='#my-container' itemdata='item' index="$index">

    </li>
  </ul>

js directive:

app.directive('thumbnail', [function() {
  return {
    restrict: 'CA',
    replace: false,
    transclude: false,
    scope: {
        index: '=index',
        item: '=itemdata'
    },
    template: '<a href="#"><img src="{{item.src}}" alt="{{item.alt}}" /></a>',
    link: function(scope, elem, attrs) {
        if (parseInt(scope.index) == 0) {
            angular.element(attrs.options).css({'background-image':'url('+ scope.item.src +')'});
        }

        elem.bind('click', function() {
            var src = elem.find('img').attr('src');

            // call your SmoothZoom here
            angular.element(attrs.options).css({'background-image':'url('+ scope.item.src +')'});
        });
    }
}
}]);

You probably would be better off adding a ng-click to the image as pointed out in another answer.

Update

The link for the demo was incorrect. It has been updated to: http://plnkr.co/edit/ybcNosdPA76J1IqXjcGG?p=preview

How to loop through a plain JavaScript object with the objects as members?

for(var k in validation_messages) {
    var o = validation_messages[k];
    do_something_with(o.your_name);
    do_something_else_with(o.your_msg);
}

Setting the correct encoding when piping stdout in Python

I had a similar issue last week. It was easy to fix in my IDE (PyCharm).

Here was my fix:

Starting from PyCharm menu bar: File -> Settings... -> Editor -> File Encodings, then set: "IDE Encoding", "Project Encoding" and "Default encoding for properties files" ALL to UTF-8 and she now works like a charm.

Hope this helps!

regular expression for finding 'href' value of a <a> link

Try this :

 public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            var res = Find(html);
        }

        public static List<LinkItem> Find(string file)
        {
            List<LinkItem> list = new List<LinkItem>();

            // 1.
            // Find all matches in file.
            MatchCollection m1 = Regex.Matches(file, @"(<a.*?>.*?</a>)",
                RegexOptions.Singleline);

            // 2.
            // Loop over each match.
            foreach (Match m in m1)
            {
                string value = m.Groups[1].Value;
                LinkItem i = new LinkItem();

                // 3.
                // Get href attribute.
                Match m2 = Regex.Match(value, @"href=\""(.*?)\""",
                RegexOptions.Singleline);
                if (m2.Success)
                {
                    i.Href = m2.Groups[1].Value;
                }

                // 4.
                // Remove inner tags from text.
                string t = Regex.Replace(value, @"\s*<.*?>\s*", "",
                RegexOptions.Singleline);
                i.Text = t;

                list.Add(i);
            }
            return list;
        }

        public struct LinkItem
        {
            public string Href;
            public string Text;

            public override string ToString()
            {
                return Href + "\n\t" + Text;
            }
        }

    }  

Input:

  string html = "<a href=\"www.aaa.xx/xx.zz?id=xxxx&name=xxxx\" ....></a> 2.<a href=\"http://www.aaa.xx/xx.zz?id=xxxx&name=xxxx\" ....></a> "; 

Result:

[0] = {www.aaa.xx/xx.zz?id=xxxx&name=xxxx}
[1] = {http://www.aaa.xx/xx.zz?id=xxxx&name=xxxx}

C# Scraping HTML Links

Scraping HTML extracts important page elements. It has many legal uses for webmasters and ASP.NET developers. With the Regex type and WebClient, we implement screen scraping for HTML.

Edited

Another easy way:you can use a web browser control for getting href from tag a,like this:(see my example)

 public Form1()
        {
            InitializeComponent();
            webBrowser1.DocumentCompleted += new WebBrowserDocumentCompletedEventHandler(webBrowser1_DocumentCompleted);
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            webBrowser1.DocumentText = "<a href=\"www.aaa.xx/xx.zz?id=xxxx&name=xxxx\" ....></a><a href=\"http://www.aaa.xx/xx.zz?id=xxxx&name=xxxx\" ....></a><a href=\"https://www.aaa.xx/xx.zz?id=xxxx&name=xxxx\" ....></a><a href=\"www.aaa.xx/xx.zz/xxx\" ....></a>";
        }

        void webBrowser1_DocumentCompleted(object sender, WebBrowserDocumentCompletedEventArgs e)
        {
            List<string> href = new List<string>();
            foreach (HtmlElement el in webBrowser1.Document.GetElementsByTagName("a"))
            {
                href.Add(el.GetAttribute("href"));
            }
        }

How to make a SIMPLE C++ Makefile

I used friedmud's answer. I looked into this for a while, and it seems to be a good way to get started. This solution also has a well defined method of adding compiler flags. I answered again, because I made changes to make it work in my environment, Ubuntu and g++. More working examples are the best teacher, sometimes.

appname := myapp

CXX := g++
CXXFLAGS := -Wall -g

srcfiles := $(shell find . -maxdepth 1 -name "*.cpp")
objects  := $(patsubst %.cpp, %.o, $(srcfiles))

all: $(appname)

$(appname): $(objects)
    $(CXX) $(CXXFLAGS) $(LDFLAGS) -o $(appname) $(objects) $(LDLIBS)

depend: .depend

.depend: $(srcfiles)
    rm -f ./.depend
    $(CXX) $(CXXFLAGS) -MM $^>>./.depend;

clean:
    rm -f $(objects)

dist-clean: clean
    rm -f *~ .depend

include .depend

Makefiles seem to be very complex. I was using one, but it was generating an error related to not linking in g++ libraries. This configuration solved that problem.

How to do a case sensitive search in WHERE clause (I'm using SQL Server)?

Just as others said, you can perform a case sensitive search. Or just change the collation format of a specified column as me. For the User/Password columns in my database I change them to collation through the following command:

ALTER TABLE `UserAuthentication` CHANGE `Password` `Password` VARCHAR(255) CHARACTER SET latin1 COLLATE latin1_general_cs NOT NULL;

Read a file in Node.js

var fs = require('fs');
var path = require('path');

exports.testDir = path.dirname(__filename);
exports.fixturesDir = path.join(exports.testDir, 'fixtures');
exports.libDir = path.join(exports.testDir, '../lib');
exports.tmpDir = path.join(exports.testDir, 'tmp');
exports.PORT = +process.env.NODE_COMMON_PORT || 12346;

// Read File
fs.readFile(exports.tmpDir+'/start.html', 'utf-8', function(err, content) {
  if (err) {
    got_error = true;
  } else {
    console.log('cat returned some content: ' + content);
    console.log('this shouldn\'t happen as the file doesn\'t exist...');
    //assert.equal(true, false);
  }
});

How to round up with excel VBA round()?

This is an example j is the value you want to round up.

Dim i As Integer
Dim ii, j As Double

j = 27.11
i = (j) ' i is an integer and truncates the decimal

ii = (j) ' ii retains the decimal

If ii - i > 0 Then i = i + 1 

If the remainder is greater than 0 then it rounds it up, simple. At 1.5 it auto rounds to 2 so it'll be less than 0.

how to change text box value with jQuery?

if you want to change the text of "input",use:

     `$("#inputId").val("what you want to put")`

and if you want to change the text in "label","span","div", you can use

     `$("#containerId").text("what you want to put")`

Free Rest API to retrieve current datetime as string (timezone irrelevant)

TimezoneDb provides a free API: http://timezonedb.com/api

GenoNames also has a RESTful API available to get the current time for a given location: http://www.geonames.org/export/ws-overview.html.

You can use Greenwich, UK if you'd like GMT.

How to stop mongo DB in one command

From the given commands I think you're on Linux.

Start MongoDB:

$ sudo service mongod start
mongod start/running, process XXXXX 

Check the Status:

$ sudo service mongod status
mongod start/running, process XXXXX 

Stop MongoDB:

$ sudo service mongod stop
mongod stop/waiting 

Why can't non-default arguments follow default arguments?

Let me clear two points here :

  • firstly non-default argument should not follow default argument , it means you can't define (a=b,c) in function the order of defining parameter in function are :
    • positional parameter or non-default parameter i.e (a,b,c)
    • keyword parameter or default parameter i.e (a="b",r="j")
    • keyword-only parameter i.e (*args)
    • var-keyword parameter i.e (**kwargs)

def example(a, b, c=None, r="w" , d=[], *ae, **ab):

(a,b) are positional parameter

(c=none) is optional parameter

(r="w") is keyword parameter

(d=[]) is list parameter

(*ae) is keyword-only

(**ab) is var-keyword parameter

  • now secondary thing is if i try something like this : def example(a, b, c=a,d=b):

argument is not defined when default values are saved,Python computes and saves default values when you define the function

c and d are not defined, does not exist, when this happens (it exists only when the function is executed)

"a,a=b" its not allowed in parameter.

appending array to FormData and send via AJAX

I've fixed the typescript version. For javascript, just remove type definitions.

  _getFormDataKey(key0: any, key1: any): string {
    return !key0 ? key1 : `${key0}[${key1}]`;
  }
  _convertModelToFormData(model: any, key: string, frmData?: FormData): FormData {
    let formData = frmData || new FormData();

    if (!model) return formData;

    if (model instanceof Date) {
      formData.append(key, model.toISOString());
    } else if (model instanceof Array) {
      model.forEach((element: any, i: number) => {
        this._convertModelToFormData(element, this._getFormDataKey(key, i), formData);
      });
    } else if (typeof model === 'object' && !(model instanceof File)) {
      for (let propertyName in model) {
        if (!model.hasOwnProperty(propertyName) || !model[propertyName]) continue;
        this._convertModelToFormData(model[propertyName], this._getFormDataKey(key, propertyName), formData);
      }
    } else {
      formData.append(key, model);
    }

    return formData;
  }

CASE (Contains) rather than equal statement

Pseudo code, something like:

CASE
  When CHARINDEX('lactulose', dbo.Table.Column) > 0 Then 'BP Medication'
ELSE ''
END AS 'Medication Type'

This does not care where the keyword is found in the list and avoids depending on formatting of spaces and commas.

Storing C++ template function definitions in a .CPP file

None of above worked for me, so here is how y solved it, my class have only 1 method templated..

.h

class Model
{
    template <class T>
    void build(T* b, uint32_t number);
};

.cpp

#include "Model.h"
template <class T>
void Model::build(T* b, uint32_t number)
{
    //implementation
}

void TemporaryFunction()
{
    Model m;
    m.build<B1>(new B1(),1);
    m.build<B2>(new B2(), 1);
    m.build<B3>(new B3(), 1);
}

this avoid linker errors, and no need to call TemporaryFunction at all

Create a new file in git bash

Yes, it is. Just create files in the windows explorer and git automatically detects these files as currently untracked. Then add it with the command you already mentioned.

git add does not create any files. See also http://gitref.org/basic/#add

Github probably creates the file with touch and adds the file for tracking automatically. You can do this on the bash as well.

NSString property: copy or retain?

Surely putting 'copy' on a property declaration flies in the face of using an object-oriented environment where objects on the heap are passed by reference - one of the benefits you get here is that, when changing an object, all references to that object see the latest changes. A lot of languages supply 'ref' or similar keywords to allow value types (i.e. structures on the stack) to benefit from the same behaviour. Personally, I'd use copy sparingly, and if I felt that a property value should be protected from changes made to the object it was assigned from, I could call that object's copy method during the assignment, e.g.:

p.name = [someName copy];

Of course, when designing the object that contains that property, only you will know whether the design benefits from a pattern where assignments take copies - Cocoawithlove.com has the following to say:

"You should use a copy accessor when the setter parameter may be mutable but you can't have the internal state of a property changing without warning" - so the judgement as to whether you can stand the value to change unexpectedly is all your own. Imagine this scenario:

//person object has details of an individual you're assigning to a contact list.

Contact *contact = [[[Contact alloc] init] autorelease];
contact.name = person.name;

//person changes name
[[person name] setString:@"new name"];
//now both person.name and contact.name are in sync.

In this case, without using copy, our contact object takes the new value automatically; if we did use it, though, we'd have to manually make sure that changes were detected and synced. In this case, retain semantics might be desirable; in another, copy might be more appropriate.

How do I make XAML DataGridColumns fill the entire DataGrid?

Make sure your DataGrid has Width set to something like {Binding Path=ActualWidth, RelativeSource={RelativeSource Mode=FindAncestor,AncestorType=Window,AncestorLevel=1}}.

Like that, your setting of Width="*" attribute on DataGrid.Columns/DataGridXXXXColumn elements should work.

String concatenation in MySQL

Use concat() function instead of + like this:

select concat(firstname, lastname) as "Name" from test.student

How to free memory in Java?

If you really want to allocate and free a block of memory you can do this with direct ByteBuffers. There is even a non-portable way to free the memory.

However, as has been suggested, just because you have to free memory in C, doesn't mean it a good idea to have to do this.

If you feel you really have a good use case for free(), please include it in the question so we can see what you are rtying to do, it is quite likely there is a better way.

Find an object in array?

Use Dollar which is Lo-Dash or Underscore.js for Swift:

import Dollar

let found = $.find(array) { $0.name == "Foo" }

SQL Server IF NOT EXISTS Usage?

Have you verified that there is in fact a row where Staff_Id = @PersonID? What you've posted works fine in a test script, assuming the row exists. If you comment out the insert statement, then the error is raised.

set nocount on

create table Timesheet_Hours (Staff_Id int, BookedHours int, Posted_Flag bit)

insert into Timesheet_Hours (Staff_Id, BookedHours, Posted_Flag) values (1, 5.5, 0)

declare @PersonID int
set @PersonID = 1

IF EXISTS    
    (
    SELECT 1    
    FROM Timesheet_Hours    
    WHERE Posted_Flag = 1    
        AND Staff_Id = @PersonID    
    )    
    BEGIN
        RAISERROR('Timesheets have already been posted!', 16, 1)
        ROLLBACK TRAN
    END
ELSE
    IF NOT EXISTS
        (
        SELECT 1
        FROM Timesheet_Hours
        WHERE Staff_Id = @PersonID
        )
        BEGIN
            RAISERROR('Default list has not been loaded!', 16, 1)
            ROLLBACK TRAN
        END
    ELSE
        print 'No problems here'

drop table Timesheet_Hours

How to find value using key in javascript dictionary

Arrays in JavaScript don't use strings as keys. You will probably find that the value is there, but the key is an integer.

If you make Dict into an object, this will work:

var dict = {};
var addPair = function (myKey, myValue) {
    dict[myKey] = myValue;
};
var giveValue = function (myKey) {
    return dict[myKey];
};

The myKey variable is already a string, so you don't need more quotes.

PHP filesize MB/KB conversion

function calcSize($size,$accuracy=2) {
    $units = array('b','Kb','Mb','Gb');
    foreach($units as $n=>$u) {
        $div = pow(1024,$n);
        if($size > $div) $output = number_format($size/$div,$accuracy).$u;
    }
    return $output;
}

Regex for string not ending with given suffix

The question is old but I could not find a better solution I post mine here. Find all USB drives but not listing the partitions, thus removing the "part[0-9]" from the results. I ended up doing two grep, the last negates the result:

ls -1 /dev/disk/by-path/* | grep -P "\-usb\-" | grep -vE "part[0-9]*$"

This results on my system:

pci-0000:00:0b.0-usb-0:1:1.0-scsi-0:0:0:0

If I only want the partitions I could do:

ls -1 /dev/disk/by-path/* | grep -P "\-usb\-" | grep -E "part[0-9]*$"

Where I get:

pci-0000:00:0b.0-usb-0:1:1.0-scsi-0:0:0:0-part1
pci-0000:00:0b.0-usb-0:1:1.0-scsi-0:0:0:0-part2

And when I do:

readlink -f /dev/disk/by-path/pci-0000:00:0b.0-usb-0:1:1.0-scsi-0:0:0:0

I get:

/dev/sdb

undefined reference to 'vtable for class' constructor

You're declaring a virtual function and not defining it:

virtual void calculateCredits();

Either define it or declare it as:

virtual void calculateCredits() = 0;

Or simply:

virtual void calculateCredits() { };

Read more about vftable: http://en.wikipedia.org/wiki/Virtual_method_table

What's the meaning of System.out.println in Java?

System - class which is final in nature. public final class System{}. Belongs to java.lang package

out - static reference variable of type PrintStream

println() - non static method in PrintStream class. PrintStream belongs to java.io package.

To understand it better you can visit : How System.out.println() Works In Java

Java Serializable Object to Byte Array

In case you want a nice no dependencies copy-paste solution. Grab the code below.

Example

MyObject myObject = ...

byte[] bytes = SerializeUtils.serialize(myObject);
myObject = SerializeUtils.deserialize(bytes);

Source

import java.io.*;

public class SerializeUtils {

    public static byte[] serialize(Serializable value) throws IOException {
        ByteArrayOutputStream out = new ByteArrayOutputStream();

        try(ObjectOutputStream outputStream = new ObjectOutputStream(out)) {
            outputStream.writeObject(value);
        }

        return out.toByteArray();
    }

    public static <T extends Serializable> T deserialize(byte[] data) throws IOException, ClassNotFoundException {
        try(ByteArrayInputStream bis = new ByteArrayInputStream(data)) {
            //noinspection unchecked
            return (T) new ObjectInputStream(bis).readObject();
        }
    }
}

Create File If File Does Not Exist

This works as well for me

string path = TextFile + ".txt";

if (!File.Exists(HttpContext.Current.Server.MapPath(path)))
{
    File.Create(HttpContext.Current.Server.MapPath(path)).Close();
}
using (StreamWriter w = File.AppendText(HttpContext.Current.Server.MapPath(path)))
{
    w.WriteLine("{0}", "Hello World");
    w.Flush();
    w.Close();
}

Forcing anti-aliasing using css: Is this a myth?

Seems like the most exhaustive solution can be found at http://www.elfboy.com/blog/text-shadow_anti-aliasing/. Works in Firefox and Chrome, although Firefox is not quite as effective as Chrome.

How can I make sticky headers in RecyclerView? (Without external lib)

Yo,

This is how you do it if you want just one type of holder stick when it starts getting out of the screen (we are not caring about any sections). There is only one way without breaking the internal RecyclerView logic of recycling items and that is to inflate additional view on top of the recyclerView's header item and pass data into it. I'll let the code speak.

import android.graphics.Canvas
import android.graphics.Rect
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import androidx.annotation.LayoutRes
import androidx.recyclerview.widget.RecyclerView

class StickyHeaderItemDecoration(@LayoutRes private val headerId: Int, private val HEADER_TYPE: Int) : RecyclerView.ItemDecoration() {

private lateinit var stickyHeaderView: View
private lateinit var headerView: View

private var sticked = false

// executes on each bind and sets the stickyHeaderView
override fun getItemOffsets(outRect: Rect, view: View, parent: RecyclerView, state: RecyclerView.State) {
    super.getItemOffsets(outRect, view, parent, state)

    val position = parent.getChildAdapterPosition(view)

    val adapter = parent.adapter ?: return
    val viewType = adapter.getItemViewType(position)

    if (viewType == HEADER_TYPE) {
        headerView = view
    }
}

override fun onDrawOver(c: Canvas, parent: RecyclerView, state: RecyclerView.State) {
    super.onDrawOver(c, parent, state)
    if (::headerView.isInitialized) {

        if (headerView.y <= 0 && !sticked) {
            stickyHeaderView = createHeaderView(parent)
            fixLayoutSize(parent, stickyHeaderView)
            sticked = true
        }

        if (headerView.y > 0 && sticked) {
            sticked = false
        }

        if (sticked) {
            drawStickedHeader(c)
        }
    }
}

private fun createHeaderView(parent: RecyclerView) = LayoutInflater.from(parent.context).inflate(headerId, parent, false)

private fun drawStickedHeader(c: Canvas) {
    c.save()
    c.translate(0f, Math.max(0f, stickyHeaderView.top.toFloat() - stickyHeaderView.height.toFloat()))
    headerView.draw(c)
    c.restore()
}

private fun fixLayoutSize(parent: ViewGroup, view: View) {

    // Specs for parent (RecyclerView)
    val widthSpec = View.MeasureSpec.makeMeasureSpec(parent.width, View.MeasureSpec.EXACTLY)
    val heightSpec = View.MeasureSpec.makeMeasureSpec(parent.height, View.MeasureSpec.UNSPECIFIED)

    // Specs for children (headers)
    val childWidthSpec = ViewGroup.getChildMeasureSpec(widthSpec, parent.paddingLeft + parent.paddingRight, view.getLayoutParams().width)
    val childHeightSpec = ViewGroup.getChildMeasureSpec(heightSpec, parent.paddingTop + parent.paddingBottom, view.getLayoutParams().height)

    view.measure(childWidthSpec, childHeightSpec)

    view.layout(0, 0, view.measuredWidth, view.measuredHeight)
}

}

And then you just do this in your adapter:

override fun onAttachedToRecyclerView(recyclerView: RecyclerView) {
    super.onAttachedToRecyclerView(recyclerView)
    recyclerView.addItemDecoration(StickyHeaderItemDecoration(R.layout.item_time_filter, YOUR_STICKY_VIEW_HOLDER_TYPE))
}

Where YOUR_STICKY_VIEW_HOLDER_TYPE is viewType of your what is supposed to be sticky holder.

How do I clear the dropdownlist values on button click event using jQuery?

A shorter alternative to the first solution given by Russ Cam would be:

$('#mySelect').val('');

This assumes you want to retain the list, but make it so that no option is selected.

If you wish to select a particular default value, just pass that value instead of an empty string.

$('#mySelect').val('someDefaultValue');

or to do it by the index of the option, you could do:

$('#mySelect option:eq(0)').attr('selected','selected'); // Select first option

How does a PreparedStatement avoid or prevent SQL injection?

PreparedStatement:

1) Precompilation and DB-side caching of the SQL statement leads to overall faster execution and the ability to reuse the same SQL statement in batches.

2) Automatic prevention of SQL injection attacks by builtin escaping of quotes and other special characters. Note that this requires that you use any of the PreparedStatement setXxx() methods to set the value.

Synchronization vs Lock

Lock makes programmers' life easier. Here are a few situations that can be achieved easily with lock.

  1. Lock in one method, and release the lock in another method.
  2. If You have two threads working on two different pieces of code, however, in the first thread has a pre-requisite on a certain piece of code in the second thread (while some other threads also working on the same piece of code in the second thread simultaneously). A shared lock can solve this problem quite easily.
  3. Implementing monitors. For example, a simple queue where the put and get methods are executed from many other threads. However, you do not want multiple put (or get) methods running simultaneously, neither the put and get method running simultaneously. A private lock makes your life a lot easier to achieve this.

While, the lock, and conditions build on the synchronized mechanism. Therefore, can certainly be able to achieve the same functionality that you can achieve using the lock. However, solving complex scenarios with synchronized may make your life difficult and can deviate you from solving the actual problem.

How to Write text file Java

It does work with me. Make sure that you append ".txt" next to timeLog. I used it in a simple program opened with Netbeans and it writes the program in the main folder (where builder and src folders are).

Setting a checkbox as checked with Vue.js

I experienced this issue and couldn't figure out a fix for a few hours, until I realised I had incorrectly prevented native events from occurring with:

<input type="checkbox" @click.prevent="toggleConfirmedStatus(render.uuid)"
    :checked="confirmed.indexOf(render.uuid) > -1"
    :value="render.uuid"
/>

removing the .prevent from the @click handler fixed my issue.

Can't install laravel installer via composer

zip extension is missing, You can avoid this error by simple running below command, It will take version by default

sudo apt-get install php-zip

In case you need any specific version, You need to mention a specific version of your php, Suppose I need to install X version of php-zip then the command will be.

sudo apt-get install phpX-zip  

Replace X with your required version, In my case, it is X = 7.3

Is there a way to use SVG as content in a pseudo element :before or :after

Yes you can! Just tested this and it works great, this is awesome! It still doesn't work with html, but it does with svg.

In my index.html I have:

<div id="test" style="content: url(test.svg); width: 200px; height: 200px;"></div>

And my test.svg looks like this:

<svg xmlns="http://www.w3.org/2000/svg">
   <circle cx="100" cy="50" r="40" stroke="black" stroke-width="2" fill="red"/>
   <polyline points="20,20 40,25 60,40 80,120 120,140 200,180" style="fill:none;stroke:black;stroke-width:3"/>
</svg> 

Get safe area inset top and bottom heights

All of the answers here are helpful, Thanks to everyone who offered help.

However as i see that that the safe area topic is a little bit confused which won’t appear to be well documented.

So i will summarize it here as mush as possible to make it easy to understand safeAreaInsets, safeAreaLayoutGuide and LayoutGuide.

In iOS 7, Apple introduced the topLayoutGuide and bottomLayoutGuide properties in UIViewController, They allowed you to create constraints to keep your content from being hidden by UIKit bars like the status, navigation or tab bar It was possible with these layout guides to specify constraints on content, avoiding it to be hidden by top or bottom navigation elements (UIKit bars, status bar, nav or tab bar…).

So for example if you wanna make a tableView starts from the top screen you have done something like that:

self.tableView.contentInset = UIEdgeInsets(top: -self.topLayoutGuide.length, left: 0, bottom: 0, right: 0)

In iOS 11 Apple has deprecated these properties replacing them with a single safe area layout guide

Safe area according to Apple

Safe areas help you place your views within the visible portion of the overall interface. UIKit-defined view controllers may position special views on top of your content. For example, a navigation controller displays a navigation bar on top of the underlying view controller’s content. Even when such views are partially transparent, they still occlude the content that is underneath them. In tvOS, the safe area also includes the screen’s overscan insets, which represent the area covered by the screen’s bezel.

Below, a safe area highlighted in iPhone 8 and iPhone X-series:

enter image description here

The safeAreaLayoutGuide is a property of UIView

To get the height of safeAreaLayoutGuide:

extension UIView {
   var safeAreaHeight: CGFloat {
       if #available(iOS 11, *) {
        return safeAreaLayoutGuide.layoutFrame.size.height
       }
       return bounds.height
  }
}

That will return the height of the Arrow in your picture.

Now, what about getting the top "notch" and bottom home screen indicator heights?

Here we will use the safeAreaInsets

The safe area of a view reflects the area not covered by navigation bars, tab bars, toolbars, and other ancestors that obscure a view controller's view. (In tvOS, the safe area reflects the area not covered by the screen's bezel.) You obtain the safe area for a view by applying the insets in this property to the view's bounds rectangle. If the view is not currently installed in a view hierarchy, or is not yet visible onscreen, the edge insets in this property are 0.

The following will show the unsafe area and there distance from edges on iPhone 8 and one of iPhone X-Series.

enter image description here

enter image description here

Now, if navigation bar added

enter image description here

enter image description here

So, now how to get the unsafe area height? we will use the safeAreaInset

Here are to solutions however they differ in an important thing,

First One:

self.view.safeAreaInsets

That will return the EdgeInsets, you can now access the top and the bottom to know the insets,

Second One:

UIApplication.shared.windows.first{$0.isKeyWindow }?.safeAreaInsets

The first one you are taking the view insets, so if there a navigation bar it will be considered , however the second one you are accessing the window's safeAreaInsets so the navigation bar will not be considered

OSError: [Errno 8] Exec format error

It wouldn't be wrong to mention that Pexpect does throw a similar error

#python -c "import pexpect; p=pexpect.spawn('/usr/local/ssl/bin/openssl_1.1.0f  version'); p.interact()"
Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/usr/lib/python2.7/site-packages/pexpect.py", line 430, in __init__
    self._spawn (command, args)
  File "/usr/lib/python2.7/site-packages/pexpect.py", line 560, in _spawn
    os.execv(self.command, self.args)
OSError: [Errno 8] Exec format error

Over here, the openssl_1.1.0f file at the specified path has exec command specified in it and is running the actual openssl binary when called.

Usually, I wouldn't mention this unless I have the root cause, but this problem was not there earlier. Unable to find the similar problem, the closest explanation to make it work is the same as the one provided by @jfs above.

what worked for me is both

  • adding /bin/bash at the beginning of the command or file you are
    facing the problem with, or
  • adding shebang #!/bin/sh as the first line.

for ex.

#python -c "import pexpect; p=pexpect.spawn('/bin/bash /usr/local/ssl/bin/openssl_1.1.0f  version'); p.interact()"
OpenSSL 1.1.0f  25 May 2017

rawQuery(query, selectionArgs)

String mQuery = "SELECT Name,Family From tblName";
Cursor mCur = db.rawQuery(mQuery, new String[]{});
mCur.moveToFirst();
while ( !mCur.isAfterLast()) {
        String name= mCur.getString(mCur.getColumnIndex("Name"));
        String family= mCur.getString(mCur.getColumnIndex("Family"));
        mCur.moveToNext();
}

Name and family are your result

jQuery change input text value

Just adding to Jason's answer, the . selector is only for classes. If you want to select something other than the element, id, or class, you need to wrap it in square brackets.

e.g.

$('element[attr=val]')

How do I fix the indentation of selected lines in Visual Studio

I like Ctrl+K, Ctrl+D, which indents the whole document.

How to get ASCII value of string in C#

This program will accept more than one character and output their ASCII value:

using System;
class ASCII
{
    public static void Main(string [] args)
    {
        string s;
        Console.WriteLine(" Enter your sentence: ");
        s = Console.ReadLine();
        foreach (char c in s)
        {
            Console.WriteLine((int)c);
        }
    }
}

PHP mPDF save file as PDF

Try this:

$mpdf->Output('my_filename.pdf','D'); 

because:

D - means Download
F - means File-save only

Cannot find or open the PDB file in Visual Studio C++ 2010

I ran into a similar problem where Visual Studio (2017) said it could not find my project's PDB file. I could see the PDB file did exist in the correct path. I had to Clean and Rebuild the project, then Visual Studio recognized the PDB file and debugging worked.

javascript regex : only english letters allowed

Another option is to use the case-insensitive flag i, then there's no need for the extra character range A-Z.

var reg = /^[a-z]+$/i;
console.log( reg.test("somethingELSE") ); //true
console.log( "somethingELSE".match(reg)[0] ); //"somethingELSE"

Here's a DEMO on how this regex works with test() and match().

Export to CSV using MVC, C# and jQuery

In addition to Biff MaGriff's answer. To export the file using JQuery, redirect the user to a new page.

$('#btn_export').click(function () {
    window.location.href = 'NewsLetter/Export';
});

How can I run a html file from terminal?

You can make the file accessible via a web server then you can use curl or lynx

Plugin org.apache.maven.plugins:maven-compiler-plugin or one of its dependencies could not be resolved

Have you tried to remove the proxy username and password? A similar poster encountered that issue:

Could not calculate build plan: Plugin org.apache.maven.plugins:maven-jar-plugin:2.3.2 or one of its dependencies could not be resolved

Failing that I found the following worked:

  1. Delete project in Eclipse (but do not delete the contents on disk)
  2. Delete all files in your Maven repository
  3. Re-download all Maven dependencies:

mvn dependency:resolve

  1. Start up Eclipse
  2. Ensure that Eclipse is configured to use your external Maven installation (Window->Preferences->Maven->Installations)
  3. Re-import the existing project(s) into Eclipse
  4. Ensure that there are no Maven Eclipse plugin errors on the final screen of the project import

Locating child nodes of WebElements in selenium

According to JavaDocs, you can do this:

WebElement input = divA.findElement(By.xpath(".//input"));

How can I ask in xpath for "the div-tag that contains a span with the text 'hello world'"?

WebElement elem = driver.findElement(By.xpath("//div[span[text()='hello world']]"));

The XPath spec is a suprisingly good read on this.

Hide separator line on one UITableViewCell

For those looking specifically for hiding separator line of an Eureka row, this is the only solution that worked for me:

     row.cellUpdate { (cell, row) in
            cell.separatorInset =  UIEdgeInsets(top: 0, left: 0, bottom: 0, right: CGFloat.greatestFiniteMagnitude)
        }

Work on a remote project with Eclipse via SSH

I had the same problem 2 years ago and I solved it in the following way:

1) I build my projects with makefiles, not managed by eclipse 2) I use a SAMBA connection to edit the files inside Eclipse 3) Building the project: Eclipse calles a "local" make with a makefile which opens a SSH connection to the Linux Host. On the SSH command line you can give parameters which are executed on the Linux host. I use for that parameter a makeit.sh shell script which call the "real" make on the linux host. The different targets for building you can give also by parameters from the local makefile --> makeit.sh --> makefile on linux host.

How to downgrade python from 3.7 to 3.6

create a virtual environment, install then switch to python 3.6.5

$ conda create -n tensorflow python=3.7
$ conda activate tensorflow
$ conda install python=3.6.5
$ pip install tensorflow

activate the environment when you would want to use tensorflow

How to use document.getElementByName and getElementByTag?

  1. The getElementsByName() method accesses all elements with the specified name. this method returns collection of elements that is an array.
  2. The getElementsByTagName() method accesses all elements with the specified tagname. this method returns collection of elements that is an array.
  3. Accesses the first element with the specified id. this method returns only a single element.

eg:

<script type="text/javascript">
    function getElements() {
        var x=document.getElementById("y");
        alert(x.value);
    }
</script>
</head>
<body>
    <input name="x" id="y" type="text" size="20" /><br />

This will return a single HTML element and display the value attribute of it.

<script type="text/javascript">
    function getElements() {
        var x=document.getElementsByName("x");
        alert(x.length);
    }
</script>
</head>
<body>
    <input name="x" id="y" type="text" size="20" /><br />
    <input name="x" id="y" type="text" size="20" /><br />

this will return an array of HTML elements and number of elements that match the name attribute.

Extracted from w3schools.

Display HTML form values in same page after submit using Ajax

Try this one:

onsubmit="return f(this.'yourfieldname'.value);"

I hope this will help you.

Eclipse CDT project built but "Launch Failed. Binary Not Found"

On a Mac, If you also have a similar problem, as Nenad Bulatovic mentioned above, you need to change the Binary Parsers.

Press Command + I to open up properties (or right click on your project and select property)

Make sure you select Mach-O 64 Parser.

enter image description here

How to export all data from table to an insertable sql format?

I know this is an old question, but victorio also asked if there are any other options to copy data from one table to another. There is a very short and fast way to insert all the records from one table to another (which might or might not have similar design).

If you dont have identity column in table B_table:

INSERT INTO A_db.dbo.A_table
SELECT * FROM B_db.dbo.B_table

If you have identity column in table B_table, you have to specify columns to insert. Basically you select all except identity column, which will be auto incremented by default.

In case if you dont have existing B_table in B_db

SELECT *
INTO B_db.dbo.B_table
FROM A_db.dbo.A_table

will create table B_table in database B_db with all existing values

Create an Android GPS tracking application

The source code for the Android mobile application open-gpstracker which you appreciated is available here.

You can checkout the code using SVN client application or via Git:

Debugging the source code will surely help you.

INSTALL_FAILED_MISSING_SHARED_LIBRARY error in Android

I got this same error when installing to an actual device. More information and a solution to loading the missing libraries to the device can be found at the following site:

Fixing the INSTALL_FAILED_MISSING_SHARED_LIBRARY Error

To set this up correctly, there are 2 key files that need to be copied to the system:

com.google.android.maps.xml

com.google.android.maps.jar

These files are located in the any of these google app packs:

http://android.d3xt3...0120-signed.zip

http://goo-inside.me...0120-signed.zip

http://android.local...0120-signed.zip

These links no longer work, but you can find the files in the android sdk if you have Google Maps API v1

After unzipping any of these files, you want to copy the files to your system, like-ah-so:

adb remount

adb push system/etc/permissions/com.google.android.maps.xml /system/etc/permissions

adb push system/framework/com.google.android.maps.jar /system/framework

adb reboot

How to convert std::chrono::time_point to calendar datetime string with fractional seconds?

If system_clock, this class have time_t conversion.

#include <iostream>
#include <chrono>
#include <ctime>

using namespace std::chrono;

int main()
{
  system_clock::time_point p = system_clock::now();

  std::time_t t = system_clock::to_time_t(p);
  std::cout << std::ctime(&t) << std::endl; // for example : Tue Sep 27 14:21:13 2011
}

example result:

Thu Oct 11 19:10:24 2012

EDIT: But, time_t does not contain fractional seconds. Alternative way is to use time_point::time_since_epoch() function. This function returns duration from epoch. Follow example is milli second resolution's fractional.

#include <iostream>
#include <chrono>
#include <ctime>

using namespace std::chrono;

int main()
{
  high_resolution_clock::time_point p = high_resolution_clock::now();

  milliseconds ms = duration_cast<milliseconds>(p.time_since_epoch());

  seconds s = duration_cast<seconds>(ms);
  std::time_t t = s.count();
  std::size_t fractional_seconds = ms.count() % 1000;

  std::cout << std::ctime(&t) << std::endl;
  std::cout << fractional_seconds << std::endl;
}

example result:

Thu Oct 11 19:10:24 2012

925

Subtracting 1 day from a timestamp date

Use the INTERVAL type to it. E.g:

--yesterday
SELECT NOW() - INTERVAL '1 DAY';

--Unrelated to the question, but PostgreSQL also supports some shortcuts:
SELECT 'yesterday'::TIMESTAMP, 'tomorrow'::TIMESTAMP, 'allballs'::TIME;

Then you can do the following on your query:

SELECT 
    org_id,
    count(accounts) AS COUNT,
    ((date_at) - INTERVAL '1 DAY') AS dateat
FROM 
    sourcetable
WHERE 
    date_at <= now() - INTERVAL '130 DAYS'
GROUP BY 
    org_id,
    dateat;


TIPS

Tip 1

You can append multiple operands. E.g.: how to get last day of current month?

SELECT date_trunc('MONTH', CURRENT_DATE) + INTERVAL '1 MONTH - 1 DAY';

Tip 2

You can also create an interval using make_interval function, useful when you need to create it at runtime (not using literals):

SELECT make_interval(days => 10 + 2);
SELECT make_interval(days => 1, hours => 2);
SELECT make_interval(0, 1, 0, 5, 0, 0, 0.0);


More info:

Date/Time Functions and Operators

datatype-datetime (Especial values).

Perl: function to trim string leading and trailing whitespace

I also use a positive lookahead to trim repeating spaces inside the text:

s/^\s+|\s(?=\s)|\s+$//g

Angular 4 setting selected option in Dropdown

Here is my example:

<div class="form-group">
    <label for="contactMethod">Contact method</label>
    <select 
        name="contactMethod" 
        id="contactMethod" 
        class="form-control"
        [(ngModel)]="contact.contactMethod">
        <option *ngFor="let method of contactMethods" [value]="method.id">{{ method.label }}</option>
    </select>
</div>

And in component you must get values from select:

contactMethods = [
    { id: 1, label: "Email" },
    { id: 2, label: "Phone" }
]

So, if you want select to have a default value selected (and proabbly you want that):

contact = {
    firstName: "CFR",
    comment: "No comment",
    subscribe: true,
    contactMethod: 2 // this id you'll send and get from backend
}

Mock a constructor with parameter

With mockito you can use withSettings(), for example if the CounterService required 2 dependencies, you can pass them as a mock:

UserService userService = Mockito.mock(UserService.class); SearchService searchService = Mockito.mock(SearchService.class); CounterService counterService = Mockito.mock(CounterService.class, withSettings().useConstructor(userService, searchService));

Concatenating Files And Insert New Line In Between Files

You can do:

for f in *.txt; do (cat "${f}"; echo) >> finalfile.txt; done

Make sure the file finalfile.txt does not exist before you run the above command.

If you are allowed to use awk you can do:

awk 'FNR==1{print ""}1' *.txt > finalfile.txt

Call asynchronous method in constructor?

Try to replace this:

myLongList.ItemsSource = writings;

with this

Dispatcher.BeginInvoke(() => myLongList.ItemsSource = writings);

npm ERR! network getaddrinfo ENOTFOUND

does your proxy require you to authenticate? because if it does, you might want you configure your proxy like this.

placeholder names. username is a placeholder for your actual username. password is a placeholder for your actual password. proxy.company.com is a placeholder for your actualy proxy *port" is your actualy port the proxy goes through. its usualy 8080

npm config set proxy "http://username:[email protected]:port"
npm config set https-proxy "http://username:[email protected]:port"

Test a string for a substring

if "ABCD" in "xxxxABCDyyyy":
    # whatever

get specific row from spark dataframe

you can simply do that by using below single line of code

val arr = df.select("column").collect()(99)

How to center cards in bootstrap 4?

i basically suggest equal gap on right and left, and setting width to auto. Here like:

.bmi {         /*my additional class name -for card*/
    margin-left: 18%;      
    margin-right: 18%;
    width: auto;
}

npm WARN ... requires a peer of ... but none is installed. You must install peer dependencies yourself

In my case following commands worked for me:

sudo npm cache clean --force
sudo npm install -g npm


sudo apt install libssl1.0-dev
sudo apt install nodejs-dev
sudo apt install node-gyp
sudo apt install npm

After that if you are facing "Cannot find module 'bcrypt' then for that you can resolve this one with below commands:

npm install node-gyp -g
npm install bcrypt -g
npm install bcrypt --save  

Hope it will work for you as well.

ASP.NET Web API - PUT & DELETE Verbs Not Allowed - IIS 8

I am not sure if you have edited right configuration file. Try following steps

  1. open %userprofile%\ducuments\iisexpress\config\applicationhost.config

  2. By default bellow given entries are commented in the applicationhost.config file. uncomment these entries.

<add name="WebDAVModule" image="%IIS_BIN%\webdav.dll" />


<add name="WebDAVModule" />
<add name="WebDAV" path="*"
 verb="PROPFIND,PROPPATCH,MKCOL,PUT,COPY,DELETE,MOVE,LOCK,UNLOCK"
 modules="WebDAVModule" resourceType="Unspecified" requireAccess="None"
 />

Getting assembly name

You could try this code which uses the System.Reflection.AssemblyTitleAttribute.Title property:

((AssemblyTitleAttribute)Attribute.GetCustomAttribute(Assembly.GetExecutingAssembly(), typeof(AssemblyTitleAttribute), false)).Title;

C# ASP.NET Single Sign-On Implementation

UltimateSAML SSO is an OASIS SAML v1.x and v2.0 specifications compliant .NET toolkit. It offers an elegant and easy way to add support for Single Sign-On and Single-Logout SAML to your ASP.NET, ASP.NET MVC, ASP.NET Core, Desktop, and Service applications. The lightweight library helps you provide SSO access to cloud and intranet websites using a single credentials entry.

Detailed UltimateSAML SSO review can be found here

How to fix committing to the wrong Git branch?

For me, this was solved by reverting the commit I had pushed, then cherry-picking that commit to the other branch.

git checkout branch_that_had_the_commit_originally
git revert COMMIT-HASH
git checkout branch_that_was_supposed_to_have_the_commit
git cherry pick COMMIT-HASH

You can use git log to find the correct hash, and you can push these changes whenever you like!

ASP.NET MVC - Find Absolute Path to the App_Data folder from Controller

Phil Haak has an example that I think is a bit more stable when dealing with paths with crazy "\" style directory separators. It also safely handles path concatenation. It comes for free in System.IO

var fileName = Path.GetFileName(file.FileName);
var path = Path.Combine(Server.MapPath("~/App_Data/uploads"), fileName);

However, you could also try "AppDomain.CurrentDomain.BaseDirector" instead of "Server.MapPath".

round() doesn't seem to be rounding properly

You can switch the data type to an integer:

>>> n = 5.59
>>> int(n * 10) / 10.0
5.5
>>> int(n * 10 + 0.5)
56

And then display the number by inserting the locale's decimal separator.

However, Jimmy's answer is better.

Adding a month to a date in T SQL

select * from Reference where reference_dt = DATEADD(mm, 1, reference_dt)

How do I suspend painting for a control and its children?

Here is a combination of ceztko's and ng5000's to bring a VB extensions version that doesn't use pinvoke

Imports System.Runtime.CompilerServices

Module ControlExtensions

Dim WM_SETREDRAW As Integer = 11

''' <summary>
''' A stronger "SuspendLayout" completely holds the controls painting until ResumePaint is called
''' </summary>
''' <param name="ctrl"></param>
''' <remarks></remarks>
<Extension()>
Public Sub SuspendPaint(ByVal ctrl As Windows.Forms.Control)

    Dim msgSuspendUpdate As Windows.Forms.Message = Windows.Forms.Message.Create(ctrl.Handle, WM_SETREDRAW, System.IntPtr.Zero, System.IntPtr.Zero)

    Dim window As Windows.Forms.NativeWindow = Windows.Forms.NativeWindow.FromHandle(ctrl.Handle)

    window.DefWndProc(msgSuspendUpdate)

End Sub

''' <summary>
''' Resume from SuspendPaint method
''' </summary>
''' <param name="ctrl"></param>
''' <remarks></remarks>
<Extension()>
Public Sub ResumePaint(ByVal ctrl As Windows.Forms.Control)

    Dim wparam As New System.IntPtr(1)
    Dim msgResumeUpdate As Windows.Forms.Message = Windows.Forms.Message.Create(ctrl.Handle, WM_SETREDRAW, wparam, System.IntPtr.Zero)

    Dim window As Windows.Forms.NativeWindow = Windows.Forms.NativeWindow.FromHandle(ctrl.Handle)

    window.DefWndProc(msgResumeUpdate)

    ctrl.Invalidate()

End Sub

End Module

Postgres could not connect to server

I got same issue because I'm using a wrong Postgres's username in code. I logged into postgres psql -d postgres and enter \du to take role name and correct Postgres's username.

So when you guys face this issue, you guys need to make sure you're using correct Postgres username, password, hostname and database...

Hope this will help anyone

Where to install Android SDK on Mac OS X?

By default the android sdk installer path is ~/Library/Android/sdk/

Force overwrite of local file with what's in origin repo?

Full sync has few tasks:

  • reverting changes
  • removing new files
  • get latest from remote repository

git reset HEAD --hard

git clean -f

git pull origin master

Or else, what I prefer is that, I may create a new branch with the latest from the remote using:

git checkout origin/master -b <new branch name>

origin is my remote repository reference, and master is my considered branch name. These may different from yours.

Order a List (C#) by many fields?

Your object should implement the IComparable interface.

With it your class becomes a new function called CompareTo(T other). Within this function you can make any comparison between the current and the other object and return an integer value about if the first is greater, smaller or equal to the second one.

IF... OR IF... in a windows batch file

Never got exist to work.

I use if not exist g:xyz/what goto h: Else xcopy c:current/files g:bu/current There are modifiers /a etc. Not sure which ones. Laptop in shop. And computer in office. I am not there.

Never got batch files to work above Windows XP

Understanding the difference between Object.create() and new SomeFunction()

Object.create(Constructor.prototype) is the part of new Constructor

this is new Constructor implementation

// 1. define constructor function

      function myConstructor(name, age) {
        this.name = name;
        this.age = age;
      }
      myConstructor.prototype.greet = function(){
        console.log(this.name, this.age)
      };

// 2. new operator implementation

      let newOperatorWithConstructor = function(name, age) {
        const newInstance = new Object(); // empty object
        Object.setPrototypeOf(newInstance, myConstructor.prototype); // set prototype

        const bindedConstructor = myConstructor.bind(newInstance); // this binding
        bindedConstructor(name, age); // execute binded constructor function

        return newInstance; // return instance
      };

// 3. produce new instance

      const instance = new myConstructor("jun", 28);
      const instance2 = newOperatorWithConstructor("jun", 28);
      console.log(instance);
      console.log(instance2);
      

new Constructor implementation contains Object.create method

      newOperatorWithConstructor = function(name, age) {
        const newInstance = Object.create(myConstructor.prototype); // empty object, prototype chaining

        const bindedConstructor = myConstructor.bind(newInstance); // this binding
        bindedConstructor(name, age); // execute binded constructor function

        return newInstance; // return instance
      };

      console.log(newOperatorWithConstructor("jun", 28));

Populate one dropdown based on selection in another

Setup mine within a closure and with straight JavaScript, explanation provided in comments

_x000D_
_x000D_
(function() {_x000D_
_x000D_
  //setup an object fully of arrays_x000D_
  //alternativly it could be something like_x000D_
  //{"yes":[{value:sweet, text:Sweet}.....]}_x000D_
  //so you could set the label of the option tag something different than the name_x000D_
  var bOptions = {_x000D_
    "yes": ["sweet", "wohoo", "yay"],_x000D_
    "no": ["you suck!", "common son"]_x000D_
  };_x000D_
_x000D_
  var A = document.getElementById('A');_x000D_
  var B = document.getElementById('B');_x000D_
_x000D_
  //on change is a good event for this because you are guarenteed the value is different_x000D_
  A.onchange = function() {_x000D_
    //clear out B_x000D_
    B.length = 0;_x000D_
    //get the selected value from A_x000D_
    var _val = this.options[this.selectedIndex].value;_x000D_
    //loop through bOption at the selected value_x000D_
    for (var i in bOptions[_val]) {_x000D_
      //create option tag_x000D_
      var op = document.createElement('option');_x000D_
      //set its value_x000D_
      op.value = bOptions[_val][i];_x000D_
      //set the display label_x000D_
      op.text = bOptions[_val][i];_x000D_
      //append it to B_x000D_
      B.appendChild(op);_x000D_
    }_x000D_
  };_x000D_
  //fire this to update B on load_x000D_
  A.onchange();_x000D_
_x000D_
})();
_x000D_
<select id='A' name='A'>_x000D_
  <option value='yes' selected='selected'>yes_x000D_
  <option value='no'> no_x000D_
</select>_x000D_
<select id='B' name='B'>_x000D_
</select>
_x000D_
_x000D_
_x000D_

Parameter in like clause JPQL

I don't know if I am late or out of scope but in my opinion I could do it like:

String orgName = "anyParamValue";

Query q = em.createQuery("Select O from Organization O where O.orgName LIKE '%:orgName%'");

q.setParameter("orgName", orgName);

Convert data file to blob

As pointed in the comments, file is a blob:

file instanceof Blob; // true

And you can get its content with the file reader API https://developer.mozilla.org/en/docs/Web/API/FileReader

Read more: https://developer.mozilla.org/en-US/docs/Using_files_from_web_applications

_x000D_
_x000D_
var input = document.querySelector('input[type=file]');
var textarea = document.querySelector('textarea');

function readFile(event) {
  textarea.textContent = event.target.result;
  console.log(event.target.result);
}

function changeFile() {
  var file = input.files[0];
  var reader = new FileReader();
  reader.addEventListener('load', readFile);
  reader.readAsText(file);
}

input.addEventListener('change', changeFile);
_x000D_
<input type="file">
<textarea rows="10" cols="50"></textarea>
_x000D_
_x000D_
_x000D_

How to create PDF files in Python

rinohtype supports embedding PDF, PNG and JPEG images (natively) and other bitmap formats (when Pillow is installed).

(Full disclosure: I am the author of rinohtype)

Remove lines that contain certain string

bad_words = ['doc:', 'strickland:','\n']

with open('linetest.txt') as oldfile, open('linetestnew.txt', 'w') as newfile:
    for line in oldfile:
        if not any(bad_word in line for bad_word in bad_words):
            newfile.write(line)

The \n is a Unicode escape sequence for a newline.

AsyncTask Android example

You need to declare the button onclicklistener. Once clicked, it calls AsyncTask class DownloadJson.

The process will be shown below:

@Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        btn = (Button) findViewById(R.id.button1);

        btn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                new DownloadJson().execute();
            }
        });
    }

    // DownloadJSON AsyncTask
    private class DownloadJson extends AsyncTask<Void, Void, Void> {
        @Override
        protected void onPreExecute() {
            super.onPreExecute();
        }

        @Override
        protected Void doInBackground(Void... params) {
            newlist = new ArrayList<HashMap<String, String>>();
            json = jsonParser.makeHttpRequest(json, "POST");
            try {
                newarray = new JSONArray(json);
                    for (int i = 0; i < countdisplay; i++) {
                        HashMap<String, String> eachnew = new HashMap<String, String>();
                        newobject = newarray.getJSONObject(i);
                        eachnew.put("id", newobject.getString("ID"));
                        eachnew.put("name", newobject.getString("Name"));
                        newlist.add(eachnew);
                    }
                }
            } catch (JSONException e) {
                Log.e("Error", e.getMessage());
                e.printStackTrace();
            }
            return null;
        }

        @Override
        protected void onPostExecute(Void args) {
            newlisttemp.addAll(newlist);
            NewAdapterpager newadapterpager = new NewAdapterpager(ProcesssActivitypager.this, newlisttemp);
            newpager.setAdapter(newadapterpager);
        }
    }

Interpreting segfault messages

Error 4 means "The cause was a user-mode read resulting in no page being found.". There's a tool that decodes it here.

Here's the definition from the kernel. Keep in mind that 4 means that bit 2 is set and no other bits are set. If you convert it to binary that becomes clear.

/*
 * Page fault error code bits
 *      bit 0 == 0 means no page found, 1 means protection fault
 *      bit 1 == 0 means read, 1 means write
 *      bit 2 == 0 means kernel, 1 means user-mode
 *      bit 3 == 1 means use of reserved bit detected
 *      bit 4 == 1 means fault was an instruction fetch
 */
#define PF_PROT         (1<<0)
#define PF_WRITE        (1<<1)
#define PF_USER         (1<<2)
#define PF_RSVD         (1<<3)
#define PF_INSTR        (1<<4)

Now then, "ip 00007f9bebcca90d" means the instruction pointer was at 0x00007f9bebcca90d when the segfault happened.

"libQtWebKit.so.4.5.2[7f9beb83a000+f6f000]" tells you:

  • The object the crash was in: "libQtWebKit.so.4.5.2"
  • The base address of that object "7f9beb83a000"
  • How big that object is: "f6f000"

If you take the base address and subtract it from the ip, you get the offset into that object:

0x00007f9bebcca90d - 0x7f9beb83a000 = 0x49090D

Then you can run addr2line on it:

addr2line -e /usr/lib64/qt45/lib/libQtWebKit.so.4.5.2 -fCi 0x49090D
??
??:0

In my case it wasn't successful, either the copy I installed isn't identical to yours, or it's stripped.

How to fix: Handler "PageHandlerFactory-Integrated" has a bad module "ManagedPipelineHandler" in its module list

  1. run cmd

  2. drag and drop Aspnet_regiis.exe into the command prompt from:

    C:\Windows\Microsoft.NET\Framework64\v2.0.50727\
    
  3. type -i (for example Aspnet_regiis.exe -i)

  4. hit enter

  5. wait until the process completes

Good luck!

React : difference between <Route exact path="/" /> and <Route path="/" />

Take a look here: https://reacttraining.com/react-router/core/api/Route/exact-bool

exact: bool

When true, will only match if the path matches the location.pathname exactly.

**path**    **location.pathname**   **exact**   **matches?**

/one        /one/two                true        no
/one        /one/two                false       yes

Difference between a SOAP message and a WSDL?

A SOAP message is a XML document which is used to transmit your data. WSDL is an XML document which describes how to connect and make requests to your web service.

Basically SOAP messages are the data you transmit, WSDL tells you what you can do and how to make the calls.

A quick search in Google will yield many sources for additional reading (previous book link now dead, to combat this will put any new recommendations in comments)

Just noting your specific questions:

Are all SOAP messages WSDL's? No, they are not the same thing at all.

Is SOAP a protocol that accepts its own 'SOAP messages' or 'WSDL's? No - reading required as this is far off.

If they are different, then when should I use SOAP messages and when should I use WSDL's? Soap is structure you apply to your message/data for transfer. WSDLs are used only to determine how to make calls to the service in the first place. Often this is a one time thing when you first add code to make a call to a particular webservice.

pandas python how to count the number of records or rows in a dataframe

To get the number of rows in a dataframe use:

df.shape[0]

(and df.shape[1] to get the number of columns).

As an alternative you can use

len(df)

or

len(df.index)

(and len(df.columns) for the columns)

shape is more versatile and more convenient than len(), especially for interactive work (just needs to be added at the end), but len is a bit faster (see also this answer).

To avoid: count() because it returns the number of non-NA/null observations over requested axis

len(df.index) is faster

import pandas as pd
import numpy as np

df = pd.DataFrame(np.arange(24).reshape(8, 3),columns=['A', 'B', 'C'])
df['A'][5]=np.nan
df
# Out:
#     A   B   C
# 0   0   1   2
# 1   3   4   5
# 2   6   7   8
# 3   9  10  11
# 4  12  13  14
# 5 NaN  16  17
# 6  18  19  20
# 7  21  22  23

%timeit df.shape[0]
# 100000 loops, best of 3: 4.22 µs per loop

%timeit len(df)
# 100000 loops, best of 3: 2.26 µs per loop

%timeit len(df.index)
# 1000000 loops, best of 3: 1.46 µs per loop

df.__len__ is just a call to len(df.index)

import inspect 
print(inspect.getsource(pd.DataFrame.__len__))
# Out:
#     def __len__(self):
#         """Returns length of info axis, but here we use the index """
#         return len(self.index)

Why you should not use count()

df.count()
# Out:
# A    7
# B    8
# C    8

Show special characters in Unix while using 'less' Command

All special, nonprintable characters are displayed using ^ notation in less. However, line feed is actually printable (just make a new line), so not considered special, so you'll have problems replacing it. If you just want to see line endings, the easiest way might be

sed -e 's/$/$/' | less

What does the [Flags] Enum Attribute mean in C#?

When working with flags I often declare additional None and All items. These are helpful to check whether all flags are set or no flag is set.

[Flags] 
enum SuitsFlags { 

    None =     0,

    Spades =   1 << 0, 
    Clubs =    1 << 1, 
    Diamonds = 1 << 2, 
    Hearts =   1 << 3,

    All =      ~(~0 << 4)

}

Usage:

Spades | Clubs | Diamonds | Hearts == All  // true
Spades & Clubs == None  // true

 
Update 2019-10:

Since C# 7.0 you can use binary literals, which are probably more intuitive to read:

[Flags] 
enum SuitsFlags { 

    None =     0b0000,

    Spades =   0b0001, 
    Clubs =    0b0010, 
    Diamonds = 0b0100, 
    Hearts =   0b1000,

    All =      0b1111

}

Resize Google Maps marker icon image

If you are using vue2-google-maps like me, the code to set the size looks like this:

<gmap-marker
  ..
  :icon="{
    ..
    anchor: { x: iconSize, y: iconSize },
    scaledSize: { height: iconSize, width: iconSize },
  }"
>

Unit testing private methods in C#

You can use PrivateObject Class

Class target = new Class();
PrivateObject obj = new PrivateObject(target);
var retVal = obj.Invoke("PrivateMethod");
Assert.AreEqual(expectedVal, retVal);

Note: PrivateObject and PrivateType are not available for projects targeting netcoreapp2.0 - GitHub Issue 366

What is offsetHeight, clientHeight, scrollHeight?

To know the difference you have to understand the box model, but basically:

clientHeight:

returns the inner height of an element in pixels, including padding but not the horizontal scrollbar height, border, or margin

offsetHeight:

is a measurement which includes the element borders, the element vertical padding, the element horizontal scrollbar (if present, if rendered) and the element CSS height.

scrollHeight:

is a measurement of the height of an element's content including content not visible on the screen due to overflow


I will make it easier:

Consider:

<element>                                     
    <!-- *content*: child nodes: -->        | content
    A child node as text node               | of
    <div id="another_child_node"></div>     | the
    ... and I am the 4th child node         | element
</element>                                    

scrollHeight: ENTIRE content & padding (visible or not)
Height of all content + paddings, despite of height of the element.

clientHeight: VISIBLE content & padding
Only visible height: content portion limited by explicitly defined height of the element.

offsetHeight: VISIBLE content & padding + border + scrollbar
Height occupied by the element on document.

scrollHeight clientHeight and offsetHeight

How to lowercase a pandas dataframe string column if it has missing values?

May be using List comprehension

import pandas as pd
import numpy as np
df=pd.DataFrame(['ONE','Two', np.nan],columns=['Name']})
df['Name'] = [str(i).lower() for i in df['Name']] 

print(df)

Difference in make_shared and normal shared_ptr in C++

I see one problem with std::make_shared, it doesn't support private/protected constructors

How to take last four characters from a varchar?

SUBSTR(column, LENGTH(column) - 3, 4)

LENGTH returns length of string and SUBSTR returns 4 characters from "the position length - 4"

Save Screen (program) output to a file

There is a command line option for logging. The output is saved to screenlog.n file, where n is a number of the screen. From man pages of screen:

‘-L’ Tell screen to turn on automatic output logging for the windows.

How to declare a global variable in C++

In addition to other answers here, if the value is an integral constant, a public enum in a class or struct will work. A variable - constant or otherwise - at the root of a namespace is another option, or a static public member of a class or struct is a third option.

MyClass::eSomeConst (enum)
MyNamespace::nSomeValue 
MyStruct::nSomeValue (static) 

How to handle a single quote in Oracle SQL

I found the above answer giving an error with Oracle SQL, you also must use square brackets, below;

SQL> SELECT Q'[Paddy O'Reilly]' FROM DUAL;


Result: Paddy O'Reilly