Tutorial by Examples: c

Python 3.x3.0 In Python 3, you can unpack an iterable without knowing the exact number of items in it, and even have a variable hold the end of the iterable. For that, you provide a variable that may collect a list of values. This is done by placing an asterisk before the name. For example, unpacki...

using namespace System; int main(array<String^>^ args) { Console::WriteLine("Hello World"); }

angular .module('app') .controller('SampleController', SampleController) SampleController.$inject = ['$log', '$scope']; function SampleController($log, $scope){ $log.debug('*****SampleController******'); /* Your code below */ } Note: The .$inject will make sure your...

There are a couple different ways to protect your controller creation from minification. The first is called inline array annotation. It looks like the following: var app = angular.module('app'); app.controller('sampleController', ['$scope', '$http', function(a, b){ //logic here }]); The...

As long as the element is a block, and it has an explicitly set width value, margins can be used to center block elements on a page horizontally. We add a width value that is lower than the width of the window and the auto property of margin then distributes the remaining space to the left and the ...

In your Visual Studio open the Solution Explorer window then right click on your project then choose Manage NuGet Packages from the menu: In the window that opens type EntityFramework in the search box in the top right. Or if you are using Visual Studio 2015 you'll see something like this: ...

The static (compile-time) type is used rather than the dynamic (run-time type) to match parameters. public class Base { public virtual string GetName() { return "Base"; } } public class Derived : Base { public override string GetName() { ...

NSDictionary *dict = [[NSDictionary alloc] initWithObjectsAndKeys:@"value1", @"key1", @"value2", @"key2", nil]; or NSArray *keys = [NSArray arrayWithObjects:@"key1", @"key2", nil]; NSArray *objects = [NSArray arrayWithObjects:@"va...

Prefer public class Order { public OrderLine AddOrderLine(OrderLine orderLine) { if (orderLine == null) throw new ArgumentNullException(nameof(orderLine)); ... } } Over public class Order { public OrderLine AddOrderLine(OrderLine orderLine) { ...

You may need to convert a Stream emitting Optional to a Stream of values, emitting only values from existing Optional. (ie: without null value and not dealing with Optional.empty()). Optional<String> op1 = Optional.empty(); Optional<String> op2 = Optional.of("Hello World");...

The function php_sapi_name() and the constant PHP_SAPI both return the type of interface (Server API) that is being used by PHP. They can be used to restrict the execution of a script to the command line, by checking whether the output of the function is equal to cli. if (php_sapi_name() === 'cli')...

A data.table is an enhanced version of the data.frame class from base R. As such, its class() attribute is the vector "data.table" "data.frame" and functions that work on a data.frame will also work with a data.table. There are many ways to create, load or coerce to a data.table....

A class marked with the keyword abstract cannot be instantiated. A class must be marked as abstract if it contains abstract members or if it inherits abstract members that it doesn't implement. A class may be marked as abstract even if no abstract members are involved. Abstract classes are usually...

float float is an alias to the .NET datatype System.Single. It allows IEEE 754 single-precision floating point numbers to be stored. This data type is present in mscorlib.dll which is implicitly referenced by every C# project when you create them. Approximate range: -3.4 × 1038 to 3.4 × 1038 Deci...

Add/remove fields in existing tables Create a migration by running: rails generate migration AddTitleToCategories title:string This will create a migration that adds a title column to a categories table: class AddTitleToCategories < ActiveRecord::Migration[5.0] def change add_column...

preg_match checks whether a string matches the regular expression. $string = 'This is a string which contains numbers: 12345'; $isMatched = preg_match('%^[a-zA-Z]+: [0-9]+$%', $string); var_dump($isMatched); // bool(true) If you pass in a third parameter, it will be populated with the matchi...

This is the Python 2 syntax, note the commas , on the raise and except lines: Python 2.x2.3 try: raise IOError, "input/output error" except IOError, exc: print exc In Python 3, the , syntax is dropped and replaced by parenthesis and the as keyword: try: raise IOErro...

Rails uses sqlite3 as the default database, but you can generate a new rails application with a database of your choice. Just add the -d option followed by the name of the database. $ rails new MyApp -T -d postgresql This is a (non-exhaustive) list of available database options: mysql oracle...

"string".upcase # => "STRING" "STRING".downcase # => "string" "String".swapcase # => "sTRING" "string".capitalize # => "String" These four methods do not modify the original receiver. For exampl...

interface IFoo { } class Foo : IFoo { } class Bar : IFoo { } var item0 = new Foo(); var item1 = new Foo(); var item2 = new Bar(); var item3 = new Bar(); var collection = new IFoo[] { item0, item1, item2, item3 }; Using OfType var foos = collection.OfType<Foo>(); // result: IEnum...