Tutorial by Examples: v

Dictionary<TKey, TValue> is a map. For a given key there can be one value in the dictionary. using System.Collections.Generic; var people = new Dictionary<string, int> { { "John", 30 }, {"Mary", 35}, {"Jack", 40} }; // Reading data Console.Wri...

To register your device for push notifications, add the following code to your AppDelegate file in didFinishLaunchingWithOptions method: Swift func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool { // Override point for c...

Unlike show.bind when using if.bind the element will be removed from the page if the supplied binding value is false or added into the page if the value is true. export class MyViewModel { isVisible = false; } <template> <div if.bind="isVisible"><strong>If ...

You can use re.finditer to iterate over all matches in a string. This gives you (in comparison to re.findall extra information, such as information about the match location in the string (indexes): import re text = 'You can try to find an ant in this string' pattern = 'an?\w' # find 'an' either w...

Assume an application with a MainActivity which can call the Next Activity using a button click. public class MainActivity extends AppCompatActivity { private final String LOG_TAG = MainActivity.class.getSimpleName(); @Override protected void onCreate(Bundle savedInstanceState) { ...

Avoid code repetition in constructors by setting a tuple of variables with a one liner: class Contact: UIView { private var message: UILabel private var phone: UITextView required init?(coder aDecoder: NSCoder) { (message, phone) = self.dynamicType.setUp() su...

//Swift let initialScreen = storyboard.instantiateInitialViewController() //Objective-c UIViewController *initailScreen = [storyboard instantiateInitialViewController];

//Swift let viewController = storyboard.instantiateViewControllerWithIdentifier("identifier") //Objective-c UIViewController *viewController = [storyboard instantiateViewControllerWithIdentifier:@"identifier"];

let view = UIView(frame: CGRect(x: 0, y: 0, width: 100, height: 100)) view.backgroundColor = UIColor.orange self.view.addSubview(view) UIView.animate(withDuration: 0.75, delay: 0.5, options: .curveEaseIn, animations: { //This will cause view to go from (0,0) to // (self.view.frame.origi...

The following is a simple example of using the strategy pattern without a context class. There are two implementation strategies which implement the interface and solve the same problem in different ways. Users of the EnglishTranslation class can call the translate method and choose which strategy t...

Intent: Define an interface for creating an object, but let sub classes decide which class to instantiate. Factory Method lets a class defer instantiation to sub classes. UML diagram: Product: It defines an interface of the objects the Factory method creates. ConcreteProduct: Implements Produc...

The Builder pattern allows you to create an instance of a class with many optional variables in an easy to read way. Consider the following code: public class Computer { public GraphicsCard graphicsCard; public Monitor[] monitors; public Processor processor; public Memory[] r...

Another way to hide admin bar is to add if ( !current_user_can( 'manage_options' ) ) { add_filter( 'show_admin_bar', '__return_false' , 1000 ); } The users who don't have privileges to access Settings page, won't be able to see the admin bar.

Converting between encodings is easy with C++11 and most compilers are able to deal with it in a cross-platform manner through <codecvt> and <locale> headers. #include <iostream> #include <codecvt> #include <locale> #include <string> using namespace std; i...

When a user press F1 on a control or click on Help button of form (?) and then clicks on a control the HelpRequested event will be raised. You can handle this event to provide custom action when user requests help for controls or form. The HelpRequested supports bubble up mechanism. It fires for y...

You can detect when a user Clicked on a HelpButton on title-bar of form by handling HelpButtonClicked. You can let the event continue or cancel it by setting Cancel property of its event args to true. private void Form1_HelpButtonClicked(object sender, CancelEventArgs e) { e.Cancel = true; ...

std::ostringstream can be used to convert any streamable type to a string representation, by inserting the object into a std::ostringstream object (with the stream insertion operator <<) and then converting the whole std::ostringstream to a std::string. For int for instance: #include <sst...

Below is a recursive code to reverse a string /** * Just a snippet to explain the idea of recursion * **/ public class Reverse { public static void main (String args[]) { String string = "hello world"; System.out.println(reverse(string)); //prints dlrow oll...

SELECT * FROM Cars WHERE status IN ( 'Waiting', 'Working' ) This is semantically equivalent to SELECT * FROM Cars WHERE ( status = 'Waiting' OR status = 'Working' ) i.e. value IN ( <value list> ) is a shorthand for disjunction (logical OR).

A pointer (resp. reference) to an object type can be converted to a pointer (resp. reference) to any other object type using reinterpret_cast. This does not call any constructors or conversion functions. int x = 42; char* p = static_cast<char*>(&x); // error: static_cast cannot perf...