Tutorial by Examples: re

public static class MyHelpers { public static MvcHtmlString MyCustomDiv(this HtmlHelper htmlHelper, string text, object htmlAttributes = null) { var mainTag = new TagBuilder("div"); mainTag.MergeAttributtes(htmlAttributes); mainTag.AddCssClas...

Let's create a small piece of code that throws an exception: private void button1_Click(object sender, EventArgs e) { string msg = null; msg.ToCharArray(); } If we execute this, we get the following Exception and stack trace: System.NullReferenceException: "Object reference not...

Set createInternetExplorerObject = CreateObject("InternetExplorer.Application") Tools> References> Microsoft Internet Controls Associated DLL: ieframe.dll Source: Internet Explorer Browser MSDN-InternetExplorer object Controls an instance of Windows Internet Explorer through...

Incorrect code Sub DoSomething() On Error GoTo CleanFail DoSomethingElse CleanFail: Debug.Print Err.Number Resume Next End Sub Why doesn't this work? If the DoSomethingElse procedure raises an error, execution jumps to the CleanFail line label, prints the error number, a...

Ubuntu: lshw is a small tool to extract detailed information on the hardware configuration of the machine. It can report exact memory configuration, firmware version, mainboard configuration, CPU version and speed, cache configuration, bus speed, etc. $ sudo lshw | less (or more) $ sudo lshw -ht...

In this example, one of two different ImageViews should be translated from the ChooserFragment to the DetailFragment. In the ChooserFragment layout we need the unique transitionName attributes: <ImageView android:id="@+id/image_first" android:layout_width="wrap_content...

Navigate to phpMyAdmin by URL http://your_ip/phpmyadmin or http://localhost/phpmyadmin Login using username root and root password. Click on Databases tab. Enter database name, select collation (you may leave it to default) and click create. Click on Privileges tab and select "Add user a...

$ grep root /etc/passwd root:x:0:0:root:/root:/bin/bash operator:x:11:0:operator:/root:/sbin/nologin

$ egrep '^(0|1)+ [a-zA-Z]+$' searchfile.txt 011 AaBBS

$ fgrep "." .bashrc # will match lines with a dot.

$ pgrep python 1299

From the tool-bar open the Java Perspective. Create a new Java project Right-click into the Package Explorer, and from the menu select New -> Java Project In the upcoming dialog enter a project name, then click Finish. Now you have the new project in your workspace. Create a new Java ...

Open Visual Studio and Select File -> New Project Select AWS Lambda Project with Tests (.NET Core) Next the Select Blueprint screen will display. Select Empty Function and Click the Finish button: Go to Tools -> NuGet Package Manager -> Package Manager Console. In the console win...

Reagent atoms are essentially the same as regular atoms in both Clojure and ClojureScript - they are essentially variables that can be altered. This is especially useful, as Clojure(Script)'s data types are mostly immutable - which means that to change the value of a variable, the variable has to be...

A usual Website just needs 3 HTTP Methods: GET, HEAD and POST. Block all other Methods by using limit_except: location / { [...] # Note: GET includes HEAD limit_except GET POST { deny all; } [...] }

import grails.rest.* @Resource(uri='/books') class Book { String title static constraints = { title blank:false } } Simply by adding the Resource transformation and specifying a URI, your domain class will automatically be available as a REST resource in either XM...

If you prefer to keep the declaration of the URL mapping in your UrlMappings.groovy file then simply removing the uri attribute of the Resource transformation and adding the following line to UrlMappings.groovy will suffice: "/books"(resources:"book") Extending your API to in...

One can describe a line in arbitrary dimensions as X = A + t*D where A and D are both vectors of suitably many dimensions. So in 2d this would be x = Ax + t*Dx y = Ay + t*Dy Now as t assumes any real value, this equation will produce all points along the line. The representation is not uniq...

The currency pipe allows you to work with you data as regular numbers but display it with standard currency formatting (currency symbol, decimal places, etc.) in the view. @Component({ selector: 'currency-pipe', template: `<div> <p>A: {{myMoney | currency:'USD':false}}</p&...

Sometimes it is required to implement Enum on your own. E.g. there is no clear way to extend other enums. Custom implementation allows this: class Enum { constructor(protected value: string) {} public toString() { return String(this.value); } public is(value: Enum | string) { ...