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You can make a URI parameter optional by adding a question mark to the route parameter. You can also specify a default value by using the form parameter=value. public class BooksController : Controller { // eg: /books // eg: /books/1430210079 [Route(“books/{isbn?}”)] public Act...

Route constraints let you restrict how the parameters in the route template are matched. The general syntax is {parameter:constraint}. For example: // eg: /users/5 [Route(“users/{id:int}”] public ActionResult GetUserById(int id) { … } // eg: users/ken [Route(“users/{name}”] public ActionRes...

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...

Sending data back to the parent, to do this we simply pass a function as a prop from the parent component to the child component, and the child component calls that function. In this example, we will change the Parent state by passing a function to the Child component and invoking that function ins...

Another way of doing aggregations is by using the Mongo.Collection#rawCollection() This can only be run on the Server. Here is an example you can use in Meteor 1.3 and higher: Meteor.methods({ 'aggregateUsers'(someId) { const collection = MyCollection.rawCollection() const aggre...

Use Nuget to install the Nancy and Nancy.Hosting.Self packages into the project. Instantiate a new NancyHost object and pass in the relevant URL using( var host = new NancyHost( hostConfiguration, new Uri( "http://localhost:1234" ) ) ) { host.Start(); Console.WriteLine( "Running o...

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(){ return ( <RefreshControl refreshing={this.state.refreshing} onRefresh={()=>this._refreshListView()} /> ) } refreshing: is the state of the spinner (true, false). onRefresh: this function will invoke when refresh the ListView/Scr...

_refreshListView(){ //Start Rendering Spinner this.setState({refreshing:true}) this.state.cars.push( {name:'Fusion',color:'Black'}, {name:'Yaris',color:'Blue'} ) //Updating the dataSource with new data this.setState({ dataSource: this.state.data...

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...

Tuples are immutable ordered collections of arbitrary distinct objects, either of the same type or of different types. Typically, tuples are constructed using the (x, y) syntax. julia> tup = (1, 1.0, "Hello, World!") (1,1.0,"Hello, World!") The individual objects of a tup...

Because Julia function parameter lists are themselves tuples, dispatching on various kinds of tuples is often easier done through the method parameters themselves, often with liberal usage for the "splatting" ... operator. For instance, consider the implementation of reverse for tuples, fr...

The IIF statement can be used in expressions to screen for division by zero: =IIF(Fields!PossibleZero.Value=0,0,Fields!Denominator.Value/IIF(Fields!PossibleZero.Value=0,1,Fields!PossibleZero.Value)) SSRS does not short circuit IIF arguments. Therefore, using a single IIF function to screen for ...

In order to use a plain-text editor to create a Console application that is written in C#, you'll need the C# Compiler. The C# Compiler (csc.exe), can be found at the following location: %WINDIR%\Microsoft.NET\Framework64\v4.0.30319\csc.exe N.B. Depending upon which version of the .NET Framework t...

using System.Diagnostics.Contracts; public int IncrementByRandomAmount(int input) { Contract.Requires<ArgumentNullException>(input != null); // Don't allow null parameter. Contract.Requires<ArgumentOutOfRangeException>(input < int.MaxValue); // We can't do anything if...

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...

Lets say you have a simple ApiController like this: [HttpGet] [Route("test")] public dynamic Test() { dynamic obj = new ExpandoObject(); obj.prop1 = "some string"; obj.prop2 = 11; obj.prop3 = "another string"; ...

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 ...

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...

docker logs --follow <containerid> This tails the output of the running container. This is useful if you did not set up a logging driver on the docker daemon.