Tutorial by Examples: in

The most common way to test Angular 2 apps is with the Jasmine test framework. Jasmine allows you to test your code in the browser. Install To get started, all you need is the jasmine-core package (not jasmine). npm install jasmine-core --save-dev --save-exact Verify To verify that Jasmine is...

Use a signal's connect method to connect a function to a signal. When a signal is sent, each connected function is called with the sender and any named arguments the signal provides. from flask import template_rendered def log_template(sender, template, context, **kwargs): sender.logger.in...

An example XML file <Sample> <Account> <One number="12"/> <Two number="14"/> </Account> <Account> <One number="14"/> <Two number="16"/> </Account&gt...

The default Angular router allows navigation to and from any route unconditionally. This is not always the desired behavior. In a scenario where a user may conditionally be allowed to navigate to or from a route, a Route Guard may be used to restrict this behavior. If your scenario fits one of the...

File main.ts (or boot.ts) Consider the examples above: Create the guard (where the Guard is created) and Add guard to route configuration, (where the Guard is configured for route, then APP_ROUTER_PROVIDERS is exported), we can couple the bootstrap to Guard as follows import { bootstrap }...

You can use the ** keyword argument unpacking operator to deliver the key-value pairs in a dictionary into a function's arguments. A simplified example from the official documentation: >>> >>> def parrot(voltage, state, action): ... print("This parrot wouldn't", ac...

Consider the following dictionaries: >>> fish = {'name': "Nemo", 'hands': "fins", 'special': "gills"} >>> dog = {'name': "Clifford", 'hands': "paws", 'color': "red"} Python 3.5+ >>> fishdog = {**fish, **dog}...

$(window).load() was deprecated in jQuery version 1.8 (and completely removed from jQuery 3.0) and as such should not be used anymore. The reasons for the deprecation are noted on the jQuery page about this event Caveats of the load event when used with images A common challenge developers attem...

Two ways to replace: by regex or by exact match. Note: the original String object will be unchanged, the return value holds the changed String. Exact match Replace single character with another single character: String replace(char oldChar, char newChar) Returns a new string resulting from...

An explicit intent is used for starting an activity or service within the same application package. In this case the name of the intended class is explicitly mentioned: Intent intent = new Intent(this, MyComponent.class); startActivity(intent); However, an implicit intent is sent across the sys...

Pretty much every header file should follow the include guard idiom: my-header-file.h #ifndef MY_HEADER_FILE_H #define MY_HEADER_FILE_H // Code body for header file #endif This ensures that when you #include "my-header-file.h" in multiple places, you don't get duplicate declara...

Router enables navigation from one view to another based on user interactions with the application. Following are the steps in implementing basic routing in Angular 2 - Basic precaution: Ensure you have the tag <base href='/'> as the first child under your head tag in your index.htm...

If you want your script to wait until a certain resource was loaded, such as an image or a PDF you can use .load(), which is a shortcut for shortcut for .on( "load", handler). HTML <img src="image.jpeg" alt="image" id="image"> jQuery $( "#imag...

You can create a UIColor from a hexadecimal number or string, e.g. 0xff00cc, "#FFFFFF" Swift Int Value extension UIColor { convenience init(hex: Int, alpha: CGFloat = 1.0) { let r = CGFloat((hex >> 16) & 0xff) / 255 let g = CGFloat((hex >> 08) &amp...

When you need to iterate over the list of jQuery elements. Consider this DOM structure: <div class="container"> <div class="red one">RED 1 Info</div> <div class="red two">RED 2 Info</div> <div class="red three"...

To select siblings of an item you can use the .siblings() method. A typical example where you want to modify the siblings of an item is in a menu: <ul class="menu"> <li class="selected">Home</li> <li>Blog</li> <li>About</li&...

Node.js is built against modern versions of V8. By keeping up-to-date with the latest releases of this engine, we ensure new features from the JavaScript ECMA-262 specification are brought to Node.js developers in a timely manner, as well as continued performance and stability improvements. All ECM...

For the character entity character(len=5), parameter :: greeting = "Hello" a substring may be referenced with the syntax greeting(2:4) ! "ell" To access a single letter it isn't sufficient to write greeting(1) ! This isn't the letter "H" but greeting(1:...

The complex entity complex, parameter :: x = (1., 4.) has real part 1. and complex part 4.. We can access these individual components as real(x) ! The real component aimag(x) ! The complex component x%re ! The real component y%im ! The complex component The x%.. form is new to F...

There are three types of comment: # This comment continues to the end of line -- This comment continues to the end of line /* This is an in-line comment */ /* This is a multiple-line comment */ Example: SELECT * FROM t1; -- this is comment CREATE TABLE stack( /*id_user int...