Tutorial by Examples: e

ViewData is the mechanism for a controller to provide data to the view it presents, without using a ViewModel. Specifically, ViewData is a dictionary which is available both in MVC action methods and views. You may use ViewData to transfer some data from your action method to the view returned by th...

List<String> data = new ArrayList<>(); data.add("Sydney"); data.add("London"); data.add("New York"); data.add("Amsterdam"); data.add("Mumbai"); data.add("California"); System.out.println(data); List<String> sor...

Initialize the UITapGestureRecognizer with a target, self in this case, and an action which is a method that has a single parameter: a UITapGestureRecognizer. After initialization, add it to the view that it should recognize taps in. Swift override func viewDidLoad() { super.viewDidLoad() ...

There are a number of collection types in Python. While types such as int and str hold a single value, collection types hold multiple values. Lists The list type is probably the most commonly used collection type in Python. Despite its name, a list is more like an array in other languages, mostl...

For instance, a computation involving commands to read and write from the prompt: First we describe the "commands" of our computation as a Functor data type {-# LANGUAGE DeriveFunctor #-} data TeletypeF next = PrintLine String next | ReadLine (String -> next) derivin...

Create an application heroku create your-app-name Deploy to Heroku git push heroku master Open your application in a browser heroku open your-app-name List Heroku commands heroku commands General help heroku help Help for a specific command heroku help <command>

Constructor functions are functions designed to construct a new object. Within a constructor function, the keyword this refers to a newly created object which values can be assigned to. Constructor functions "return" this new object automatically. function Cat(name) { this.name = name;...

Each time you use a selector in jQuery the DOM is searched for elements that match your query. Doing this too often or repeatedly will decrease performance. If you refer to a specific selector more than once you should add it to the cache by assigning it to a variable: var nav = $('#navigation'); ...

Using the apt package manager sudo apt-get update sudo apt-get install nodejs sudo apt-get install npm sudo ln -s /usr/bin/nodejs /usr/bin/node # the node & npm versions in apt are outdated. This is how you can update them: sudo npm install -g npm sudo npm install -g n sudo n stabl...

There are two parts of a class: the interface and the implementation. The interface is the exposed functionality of the class. Its public methods and variables are part of the interface. The implementation is the internal workings of a class. Other classes shouldn't need to know about the implemen...

Encapsulation allows you to make internal changes to a class without affecting any code that calls the class. This reduces coupling, or how much any given class relies on the implementation of another class. For example, let's change the implementation of the Angle class from the previous example: ...

When implementing more than one interface that have methods of the same name that include default implementations, it is ambiguous to the compiler which implementation should be used. In the case of a conflict, the developer must override the conflicting method and provide a custom implementation. ...

Empty array np.empty((2,3)) Note that in this case, the values in this array are not set. This way of creating an array is therefore only useful if the array is filled later in the code. From a list np.array([0,1,2,3]) # Out: array([0, 1, 2, 3]) Create a range np.arange(4) # Out: array(...

x = np.arange(4) x #Out:array([0, 1, 2, 3]) scalar addition is element wise x+10 #Out: array([10, 11, 12, 13]) scalar multiplication is element wise x*2 #Out: array([0, 2, 4, 6]) array addition is element wise x+x #Out: array([0, 2, 4, 6]) array multiplication is element wise x...

Slice syntax is i:j:k where i is the starting index (inclusive), j is the stopping index (exclusive) and k is the step size. Like other python data structures, the first element has an index of 0: x = np.arange(10) x[0] # Out: 0 x[0:4] # Out: array([0, 1, 2, 3]) x[0:4:2] # Out:array([0, 2...

The basics After making changes to your source code, you should stage those changes with Git before you can commit them. For example, if you change README.md and program.py: git add README.md program.py This tells git that you want to add the files to the next commit you do. Then, commit your...

Notation As of jQuery 3.0, only this form is recommended: jQuery(function($) { // Run when document is ready // $ (first argument) will be internal reference to jQuery // Never rely on $ being a reference to jQuery in the global namespace }); All other document-ready handlers are depr...

Compares two values for equality. It can compare strings, integers, and Boolean values only. Assert.AreEqual(documentElement.LocalName, "xamlControls", "Xaml files must have a root node named 'xamlControls'.");

$(element).hide() // sets display: none $(element).show() // sets display to original value $(element).toggle() // toggles between the two $(element).is(':visible') // returns true or false $('element:visible') // matches all elements that are visible $...

If an object is defined with static, thread, or automatic storage duration, and it has a character type, either: char, unsigned char, or signed char, it may not be accessed by a non-character type. In the below example a char array is reinterpreted as the type int, and the behavior is undefined on e...