Tutorial by Examples: c

A more comprehensive authentication POST request with Jsoup

Most websites require a much more complicated process than the one demonstrated above. Common steps for logging into a website are: Get the unique cookie from the initial login form. Inspect the login form to see what the destination url is for the authentication request Parse the login form t...

Jsoup • Logging into websites with Jsoup

Parsing JavaScript Generated Page with Jsoup and HtmUnit

page.html - source code <html> <head> <script src="loadData.js"></script> </head> <body onLoad="loadData()"> <div class="container"> <table id="data" border="1"> <...

Jsoup • Parsing Javascript Generated Pages

Structure of a Simple ASP Page

<%@ Language="VBScript" CodePage = 65001 %> <% Option Explicit Response.Charset = "UTF-8" Response.CodePage = 65001 %> <!doctype html> <html> <head> <title>My First Classic ASP Page</title> </head> <body&gt...

asp-classic • Getting started with asp-classic

Basic usage

For a thick arrow pointing north in a span, add classes ui-icon and ui-icon-arrowthick-1-n: <span class="ui-icon ui-icon-arrowthick-1-n"></span> For a triangle pointing south in a span, add classes ui-icon and ui-icon-triangle-1-s: <span class="ui-icon ui-icon-tria...

jQuery UI Library • Icons

@CompileStatic

Enables a code to be statically compiled. Its bytecode will be closer to Java's, thus having better performance, though some dynamic features won't be available. @groovy.transform.CompileStatic class ListMath { def countSize(List<String> strings) { strings.collect { it.size() }...

groovy • AST Transformations

Using the default Form instance

VB.NET offers default Form instances. The developer does not need to create the instance as it is created behind the scenes. However, it is not preferable to use the default instance all but the simplest programs. Public Class Form1 Public Sub Foo() MessageBox.Show("Bar") ...

Visual Basic .NET Language • Working with Windows Forms

Using uWSGI to run a flask application

The built-in werkzeug server certainly is not suitable for running production servers. The most obvious reason is the fact that the werkzeug server is single-threaded and thus can only handle one request at a time. Because of this we want to use the uWSGI Server to serve our application instead. In...

Flask • Deploying Flask application using uWSGI web server with Nginx

CRTP to avoid code duplication

The example in Visitor Pattern provides a compelling use-case for CRTP: struct IShape { virtual ~IShape() = default; virtual void accept(IShapeVisitor&) const = 0; }; struct Circle : IShape { // ... // Each shape has to implement this method the same way ...

C++ • Curiously Recurring Template Pattern (CRTP)

Pitfall: using == to compare strings

A common mistake for Java beginners is to use the == operator to test if two strings are equal. For example: public class Hello { public static void main(String[] args) { if (args.length > 0) { if (args[0] == "hello") { System.out.println(&q...

Java Language • Common Java Pitfalls

Creating zip archive from directory

System.IO.Compression.ZipFile.CreateFromDirectory("myfolder", "archive.zip") Create archive.zip file containing files which are in myfolder. In example paths are relative to program working directory. You can specify absolute paths.

Visual Basic .NET Language • File/Folder Compression

Extracting zip archive to directory

System.IO.Compression.ZipFile.ExtractToDirectory("archive.zip", "myfolder") Extracts archive.zip to myfolder directory. In example paths are relative to program working directory. You can specify absolute paths.

Visual Basic .NET Language • File/Folder Compression

Create zip archive dynamicaly

' Create filestream to file Using fileStream = New IO.FileStream("archive.zip", IO.FileMode.Create) ' open zip archive from stream Using archive = New System.IO.Compression.ZipArchive(fileStream, IO.Compression.ZipArchiveMode.Create) ' create file_in_archive.txt in arch...

Visual Basic .NET Language • File/Folder Compression

Reads file (/etc/passwd) line by line and field by field

#!/bin/bash FILENAME="/etc/passwd" while IFS=: read -r username password userid groupid comment homedir cmdshell do echo "$username, $userid, $comment $homedir" done < $FILENAME In unix password file, user information is stored line by line, each line consisting of i...

Bash • Read a file (data stream, variable) line-by-line (and/or field-by-field)?

How to compose values and functions using common operators

In Object Oriented Programming a common task is to compose objects (values). In Functional Programming it is as common task to compose values as well as functions. We are used to compose values from our experience of other programming languages using operators like +, -, *, / and so on. Value co...

F# • Operators

Adding a UIRefreshControl to a TableView

Assumptions: TableView - reference to the TableView DataSource - is a class which inherits UITableViewSource DataSource.Objects - is a public List< object >(), accessible to the UIViewController private UIRefreshControl refreshControl; public override void ViewDidLoad() { base.V...

Xamarin.iOS • Adding UIRefreshControl to a table view

Object Initializers

Named Types Dim someInstance As New SomeClass(argument) With { .Member1 = value1, .Member2 = value2 '... } Is equivalent to Dim someInstance As New SomeClass(argument) someInstance.Member1 = value1 someInstance.Member2 = value2 '... Anonymous Types (Option...

Visual Basic .NET Language • Introduction to Syntax

Collection Initializer

Arrays Dim names = {"Foo", "Bar"} ' Inferred as String() Dim numbers = {1, 5, 42} ' Inferred as Integer() Containers (List(Of T), Dictionary(Of TKey, TValue), etc.) Dim names As New List(Of String) From { "Foo", "Bar" '... ...

Visual Basic .NET Language • Introduction to Syntax

Dictionaries are unordered

You might expect a Python dictionary to be sorted by keys like, for example, a C++ std::map, but this is not the case: myDict = {'first': 1, 'second': 2, 'third': 3} print(myDict) # Out: {'first': 1, 'second': 2, 'third': 3} print([k for k in myDict]) # Out: ['second', 'third', 'first'] Py...

Python Language • Common Pitfalls

RecordWildCards

See RecordWildCards

Haskell Language • Common GHC Language Extensions

POSIX Timer with SIGEV_THREAD notification

This example demonstrates POSIX Timer usage with CLOCK_REALTIME clock and SIGEV_THREAD notification method. #include <stdio.h> /* for puts() */ #include <string.h> /* for memset() */ #include <unistd.h> /* for sleep() */ #include <stdlib.h> /* for EXIT_SUCCESS */ #inc...

POSIX • Timers