Tutorial by Examples: w

OPERATORS $postsGreaterThan = Post::find()->where(['>', 'created_at', '2016-01-25'])->all(); // SELECT * FROM post WHERE created_at > '2016-01-25' $postsLessThan = Post::find()->where(['<', 'created_at', '2016-01-25'])->all(); // SELECT * FROM post WHERE created_at < '2...

<?php namespace models; use yii\db\ActiveRecord; use yii\behaviors\TimestampBehavior; class Post extends ActiveRecord { public static function tableName() { return 'post'; } public function rules() { ...

Twig is a templating language that compiles to optimized PHP code. It is primarily used for outputting HTML, but can also be used to output any other text-based format. It is a standalone component that can be easily integrated into any PHP project. It provides many excellent features: Autoescap...

You have to keep the operator precedence in mind when using await keyword. Imagine that we have an asynchronous function which calls another asynchronous function, getUnicorn() which returns a Promise that resolves to an instance of class Unicorn. Now we want to get the size of the unicorn using th...

When accessing arrays with pointers, there are no bounds check and therefore no IndexOutOfRangeException will be thrown. This makes the code faster. Assigning values to an array with a pointer: class Program { static void Main(string[] args) { unsafe { int...

CSS3 introduces a few new units, including the rem unit, which stands for "root em". Let's look at how rem works. First, let's look at the differences between em and rem. em: Relative to the font size of the parent. This causes the compounding issue rem: Relative to the font size of t...

Prerequisites iOS 8 or later, macOS 10.9 or later, all versions of tvOS and watchOS. Xcode 8.0 or later required. Realm Swift 2.3.0 was the last version to support Swift 2.x and Xcode 7.3. Installation Dynamic Framework Download the latest release of Realm and extract the zip....

The second value in the curly braces dictates the length of the replacement string. By adjusting the second value to be positive or negative, the alignment of the string can be changed. string.Format("LEFT: string: ->{0,-5}<- int: ->{1,-5}<-", "abc", 123); string....

Use existing .NET classes instantly with PowerShell by using [class]::Method(args): PS C:\> [guid]::NewGuid() Guid ---- 8874a185-64be-43ed-a64c-d2fe4b6e31bc Similarly, in PowerShell 5+ you may use the New-Guid cmdlet: PS C:\> New-Guid Guid ---- 8874a185-64be-43ed-a64c-d2fe4b6e31...

import std.stdio; // Let's get going! void main() { writeln("Hello World!"); } To compile and run, save this text as a file called main.d. From the command line run dmd main.d to compile the program. Finally, run ./main to execute the program in a bash shell or you can click ...

If value types are assigned to variables of type object they are boxed - the value is stored in an instance of a System.Object. This can lead to unintended consequences when comparing values with ==, e.g.: object left = (int)1; // int in an object box object right = (int)1; // int in an object bo...

Create a circle image with glide. public class CircleTransform extends BitmapTransformation { public CircleTransform(Context context) { super(context); } @Override protected Bitmap transform(BitmapPool pool, Bitmap toTransform, int outWidth, int outHeight) { ret...

All C functions are in actuality pointers to a spot in the program memory where some code exists. The main use of a function pointer is to provide a "callback" to other functions (or to simulate classes and objects). The syntax of a function, as defined further down on this page is: retu...

function foo() { console.trace('My log statement'); } foo(); Will display this in the console: My log statement VM696:1 foo @ VM696:1 (anonymous function) @ (program):1 Note: Where available it's also useful to know that the same stack trace is accessible a...

It is worth noting that in swift, unlike other languages people are familiar with, there is an implicit break at the end of each case statement. In order to follow through to the next case (i.e. have multiple cases execute) you need to use fallthrough statement. switch(value) { case 'one': //...

Use the Bash shell's filename expansion and brace expansion capabilities to obtain the filenames: # display the files and directories that are in the current directory printf "%s\n" * # display only the directories in the current directory printf "%s\n" */ # display only...

In this example we have an existing table, SuperHeros. This table contains a primary key ID. We will add a new table in order to store the powers of each super hero: CREATE TABLE HeroPowers ( ID int NOT NULL PRIMARY KEY, Name nvarchar(MAX) NOT NULL, HeroId int REFERENCES SuperHero...

Swift import SystemConfiguration /// Class helps to code reuse in handling internet network connections. class NetworkHelper { /** Verify if the device is connected to internet network. - returns: true if is connected to any internet network, false if is not co...

\bfoo\b will match the complete word with no alphanumeric and _ preceding or following by it. Taking from regularexpression.info There are three different positions that qualify as word boundaries: Before the first character in the string, if the first character is a word character. After...

NSSet *set = [NSSet set]; NSArray *array = [NSArray array]; NSArray *fromSet = [set allObjects]; NSSet *fromArray = [NSSet setWithArray:array];