Tutorial by Examples: d

EntityFramewok Fluent API is a powerful and elegant way of mapping your code-first domain models to underlying database. This also can be used with code-first with existing database. You have two options when using Fluent API: you can directly map your models on OnModelCreating method or you can cre...

By using the .IsRequired() method, properties can be specified as mandatory, which means that the column will have a NOT NULL constraint. using System.Data.Entity; // .. public class PersonContext : DbContext { // .. protected override void OnModelCreating(DbModelBuilder modelB...

There are two common ways to encode a POST request body: URL encoding (application/x-www-form-urlencoded) and form data (multipart/form-data). Much of the code is similar, but the way you construct the body data is different. Sending a request using URL encoding Be it you have a server for your s...

A pointer is declared much like any other variable, except an asterisk (*) is placed between the type and the name of the variable to denote it is a pointer. int *pointer; /* inside a function, pointer is uninitialized and doesn't point to any valid object yet */ To declare two pointer variables...

Media queries are not supported at all in IE8 and below. A Javascript based workaround To add support for IE8, you could use one of several JS solutions. For example, Respond can be added to add media query support for IE8 only with the following code : <!--[if lt IE 9]> <script ...

"The :nth-child(an+b) CSS pseudo-class matches an element that has an+b-1 siblings before it in the document tree, for a given positive or zero value for n" - MDN :nth-child pseudo-selector12345678910:first-child✔:nth-child(3)✔:nth-child(n+3)✔✔✔✔✔✔✔✔:nth-child(3n)✔✔✔:nth-child(3n+1)...

Using alarm, user can schedule SIGALARM signal to be raised after specified interval. In case user did not blocked, ignored or specified explicit signal handler for this signal, the default action for this signal will be performed on arrival. Per specification default action for SIGALARM is to termi...

This program demonstrates how to run another process using fork() and wait its termination using waitpid(): fork() creates an identical copy of the current process. The original process is the parent process, while the newly created one is the child process. Both processes continue exactly afte...

If a class, enum, inline function, template, or member of a template has external linkage and is defined in multiple translation units, all definitions must be identical or the behavior is undefined according to the One Definition Rule (ODR). foo.h: class Foo { public: double x; private...

The complete sample code for this application (Android + Node server) is available in the PayPal Developer Github repository. The first stage of creating the Android portion of our application is to set up a basic layout and handle responses that come back from the server that we'll set up in Node....

The complete sample code for this application (Android + Node server) is available in the PayPal Developer Github repository. At this point the PayPal future payments button has been clicked, we have an auth code and metadata ID from the PayPal SDK, and we need to pass those on to our server to com...

The complete sample code for this application (Android + Node server) is available in the PayPal Developer Github repository. From step 2, an async request has been made to our server at the /fpstore endpoint, passing along the auth code and metadata ID. We now need to exchange those for a token in...

XSD schema (schema.xsd) The following xml schema (xsd) defines a list of users with attributes name and reputation. <?xml version="1.0"?> <xs:schema version="1.0" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:ns="http://www...

Review Partial Application before proceeding. In Haskell, a function that can take other functions as arguments or return functions is called a higher-order function. The following are all higher-order functions: map :: (a -> b) -> [a] -> [b] filter :: (a -> Bool) -> [a] ...

Lets say we have a class Classy that has property Propertua public class Classy { public string Propertua {get; set;} } to set Propertua using reflection: var typeOfClassy = typeof (Classy); var classy = new Classy(); var prop = typeOfClassy.GetProperty("Propertua"); prop.Se...

When editing text, a common task is to navigate to a particular word on the screen. In these examples we explore how we can navigate to the word updated. For the sake of consistency across the examples, we aim to land on the first letter of the word. Mid-screen jump M$B This approach is quick...

An example of code showing how nodes can be inserted at a doubly linked list, how the list can easily be reversed, and how it can be printed in reverse. #include <stdio.h> #include <stdlib.h> /* This data is not always stored in a structure, but it is sometimes for ease of use */ s...

The markdown help states Available conditionals are gt, gte, lt, lte, eq, and neq. <!-- if version [eq C++03] --> eq equal to <!-- end version if --> <!-- if version [neq C++03] --> neq not equal to <!-- end version if --> <!-- if version [gt C++03] -...

Multiple conditions can be used. <!-- if version [lte 1.2.0] [gt 1.3.12] [gt 1.4.9] [neq 1.2.0] [eq 1.5.7] --> content <!-- end version if -->

The macros @spawn and @spawnat are two of the tools that Julia makes available to assign tasks to workers. Here is an example: julia> @spawnat 2 println("hello world") RemoteRef{Channel{Any}}(2,1,3) julia> From worker 2: hello world Both of these macros will evaluate an ex...