Tutorial by Examples: b

NumberBox

Often you will want to have an input box that takes numbers only. Again by deriving from the standard controls this is easily achieved, for example: using System; using System.Windows.Forms; using System.Globalization; namespace StackOverflowDocumentation { public class SONumberBox : SO...

winforms • Inheriting Controls

Using ajax in vanilla javascript with a simple callback

Here is our function to create a simple ajax call written in vanilla javascript (not es2015): function ajax(url, callback) { var xhr; if(typeof XMLHttpRequest !== 'undefined') xhr = new XMLHttpRequest(); else { var versions = ["MSXML2.XmlHttp.5.0", ...

ajax • Getting started with ajax

One to One Hibernate Mapping

Every Country has one Capital. Every Capital has one Country. Country.java package com.entity; import javax.persistence.Column; import javax.persistence.Entity; import javax.persistence.GeneratedValue; import javax.persistence.GenerationType; import javax.persistence.Id; import javax.persist...

hibernate • Mapping associations

ETL from web API's with modules json and requests

First, import modules and set connection strings. If you need parameters, you can either put them directly in the URL string (an API in this case) or build them as a dict and pass them to the params argument. import requests import json params = {'id': 'blahblah', 'output': 'json'} # You could ...

python-requests • Sending and receiving JSON

Installation using UMD build

A build is also available on npmcdn. You can include the script like this: <script src="https://npmcdn.com/react-router/umd/ReactRouter.min.js"></script> The library will be available globally on window.ReactRouter.

React Router • Getting started with React Router

How to connect Realtime database with Android Application

How to implement FirebaseRealTime database in android application. Following is the steps for do it. First install firebase sdk, If you dont know how to install then following is the URL for help. Install Firebase SDK After thet register your project in firbase console, URL of the firbas...

firebase • Firbase Realtime Database with Android

Generic httpInterceptor step by step

Create an HTML file with the following content: <!DOCTYPE html> <html> <head> <title>Angular Interceptor Sample</title> <script src="https://code.angularjs.org/1.5.8/angular.min.js"></script> <script src="app.js"></sc...

AngularJS • HTTP Interceptor

Find all elements with a certain attribute

Imagine the following XML: <root> <element foobar="hello_world" /> <element example="this is one!" /> </root> /root/element[@foobar] and will return the <element foobar="hello_world" /> element.

xpath • Finding elements containing specific attributes

Find all elements with a certain attribute value

Imagine the following XML: <root> <element foobar="hello_world" /> <element example="this is one!" /> </root> The following XPath expression: /root/element[@foobar = 'hello_world'] will return the <element foobar="hello_world&quo...

xpath • Finding elements containing specific attributes

Socket basics

There are four types of sockets available in POSIX API: TCP, UDP, UNIX, and (optionally) RAW. Unix domain sockets may act like stream sockets or like datagram sockets. Some of endpoint types: struct sockaddr - universal endpoint type. Typically, other concrete endpoint types are converted to thi...

POSIX • Sockets

Model Validation with Custom Attribute

If the built in attributes are not sufficient to validate your model data, then you can place your validation logic in a class derived from ValidationAttribute. In this example only odd numbers are valid values for a model member. Custom Validation Attribute public class OddNumberAttribute : Valid...

asp.net-core • Models

Basic program for signup

Through this example, it will be explained to divide the node.js code into different modules/folders for better undertandibility. Following this technique makes it easier for other developers to understand the code as he can directly refer to concerned file instead of going through whole code. The m...

Node.js • Good coding style

Attribute Routing in Areas

For using Attribute Routing in areas, registering areas and [RouteArea(...)] definitions are required. In RouteConfig.cs : public class RouteConfig { public static void RegisterRoutes(RouteCollection routes) { routes.IgnoreRoute("{resource}.axd/{*pathInfo}"); ...

asp.net-mvc • Routing

Un-pivot a dynamic set of columns based on condition

The following example is a very useful basis when you are trying to convert transaction data to un-pivoted data for BI/reporting reasons, where the dimensions which are to be un-pivoted can have a dynamic set of columns. For our example, we suppose that the raw data table contains employee assessme...

MySQL • Dynamic Un-Pivot Table using Prepared Statement

C# implementation of OpenCL 1.2: number of platforms for an AMD system in 64-bit windows

OpenCL is low level api so it must be implemented in "C space" first. For that, one needs to download header files from Khronos' site. My hardware is AMD and capable of version 1.2, downloading opencl.h cl_platform.h cl.h cl_ext.h cl_egl.h cl_dx9_media_sharing.h cl_d3d10.h c...

opencl • Getting started with opencl

Basic mongodump of local default mongod instance

mongodump --db mydb --gzip --out "mydb.dump.$(date +%F_%R)" This command will dump a bson gzipped archive of your local mongod 'mydb' database to the 'mydb.dump.{timestamp}' directory

MongoDB • Backing up and Restoring Data

Basic mongorestore of local default mongod dump

mongorestore --db mydb mydb.dump.2016-08-27_12:44/mydb --drop --gzip This command will first drop your current 'mydb' database and then restore your gzipped bson dump from the 'mydb mydb.dump.2016-08-27_12:44/mydb' archive dump file.

MongoDB • Backing up and Restoring Data

Find my brother

XML <GrandFather name="Bardock" gender="male" spouse="Gine"> <Dad name="Goku" gender="male" spouse="Chi Chi"> <brother name="Goten" gender="male" /> <Me name="Gohan" gender=&q...

xpath • Get nodes relative to the current node

Get all avatars before Parashurama

XML <Dashavatar> <Avatar name="Matsya"/> <Avatar name="Kurma"/> <Avatar name="Varaha"/> <Avatar name="Narasimha"/> <Avatar name="Vamana"/> <Avatar name="Balabhadra"/> ...

xpath • Get nodes relative to the current node

The Basic System

As the first step, we’ll build a basic web server that stores data in MongoDB. For this demonstration, we’ll name it “fast Library”. The server will have two basic operations: POST /book: This endpoint will receive the title, the author, and the content of the book, and create a book entry in the d...

spring-boot • Caching with Redis Using Spring Boot for MongoDB