Tutorial by Examples: w

This serializer has some nice features that the default .net json serializer doesn't have, like Null value handling, you just need to create the JsonSerializerSettings : public static string Serialize(T obj) { string result = JsonConvert.SerializeObject(obj, new JsonSerializerSettings { NullVa...

Pretext This is an introduction to the Hello World program example on the Raspberry Pi written in C. The following example makes use of the command line interface and is set up as a step-by-step guide. Along with creating a Hello World program, the reader will be introduced to simple linux comman...

Example: Customers who can create a post. Each customer can create multiple posts. As soon as customer creates the post, post will be under administrators review. Now we have to fetch the customers list who have all active posts by using sub-query. Note: If a customer has 5 post, among 5 posts if h...

Java Code import org.opencv.core.Mat; import org.opencv.core.MatOfRect; import org.opencv.core.Point; import org.opencv.core.Rect; import org.opencv.core.Scalar; import org.opencv.highgui.Highgui; import org.opencv.highgui.VideoCapture; import org.opencv.objdetect.CascadeClassifier; publ...

When you want to work with the data entries in arrays you first need to unwind the array. The unwind operation creates a document for each entry in the array. When you have lot's of documents with large arrays you will see an explosion in number of documents. { "_id" : 1, "item"...

RefreshControl is used inside a ScrollView or ListView to add pull to refresh functionality. at this example we will use it with ListView 'use strict' import React, { Component } from 'react'; import { StyleSheet, View, ListView, RefreshControl, Text } from 'react-native' class RefreshContr...

Sometimes you need to replace a value matching a pattern with a new value that's based on that specific match, making it impossible to predict the new value. For these types of scenarios, a MatchEvaluator can be very useful. In PowerShell, a MatchEvaluator is as simple as a scriptblock with a singl...

This example attempts to mimic the behavior of the built-in path construction operators like arc. If there is a current point, poly first draws a line to (x,y)+(r,0), otherwise it starts by moving to that point. Instead of gsave ... grestore (which has the undesirable effect of discarding the very...

Create an instance of Mobile Analytics for Bluemix. Add the Bluemix Mobile Services SDK to your iOS project. After installing the SDK, add these import statements at top of your AppDelegate.swift file: import BMSCore import BMSAnalytics Next you'll need to initialize and send mobile ana...

It is sometimes useful to integrate a custom error logging framework to ensure all exceptions are logged. [ServiceContract] [ErrorHandler] public interface IMyService { } [AttributeUsage(AttributeTargets.Interface)] public class CustomErrorHandler : Attribute, IContractBehavior, IE...

Setup Install AWS CLI AWS CLI is an common CLI tool for managing the AWS resources. With this single tool we can manage all the aws resources sudo apt-get install -y python-dev python-pip sudo pip install awscli aws --version aws configure Bash one-liners cat <file> # output a file ...

This example shows how to take image and display it correctly on the Android device. Firstly we have to create sample application with one button and one imageview. Once user clicks on the button camera is launched and after user selects picture it will be displayed with the proper orientation on ...

As the official website of Swagger says : Swagger is to define a standard, language-agnostic interface to REST APIs which allows both humans and computers to discover and understand the capabilities of the service without access to source code, documentation, or through network traffic inspection. ...

List of commonly used S3 AWS CLI Commands Create Bucket aws s3 mb s3://bucket-name Remove Bucket aws s3 rb s3://bucket-name List Buckets aws s3 ls List contents inside the bucket aws s3 ls s3://bucket-name List Bucket with a path aws s3 ls s3://bucket-name/path Copy file aws s3...

In this example, I created a form which is used to register a new user. In the options passed to the form, I give the different roles a user can have. Creating a reusable class for my form with configured data class and an extra option that fills the choice field to pick a userrole: class UserType...

To be able do deal with form events, it's important to attach the request, that is send to a controller action after submitting a form, to the form created in that action. public function registerAction(Request $request) { $data = new ExampleObject(); $form = $this->createForm(Example...

If you use the LOAD DATA INFILE command to populate a table with existing data, you will often find that the import fails due to duplicates. There are several possible ways to overcome this problem. LOAD DATA LOCAL If this option has been enabled in your server, it can be used to load a file that ...

By default the ArrayAdapter creates a view for each array item by calling toString() on each item and placing the contents in a TextView. Example: ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, myStringArray); where androi...

To do that, [download][1] a required amCharts product ZIP archive. Unzip it and place somewhere on your web server. I.e. in /amcharts/ sub-directory. Then simply load them using <script> tags: <script src="amcharts/amcharts.js"></script> <script src="amcharts/...

wxPython Phoenix is the latest version of wxPython, (currently Sept 2016 without an official release). It supports both Python 2 and Python 3. You can download a snapshot build (i.e. a Python wheel) for your platform and Python version here. wxPython Phoenix utilizes a largely automated mechanism ...