Tutorial by Examples: n

$ react-native start On latest version of React Native, no need to run the packager. It will run automatically. By default this starts the server at port 8081. To specify which port the server is on $ react-native start --port PORTNUMBER

The reduce method reduces the collection to a single value, passing the result of each iteration into the subsequent iteration. Please see reduce method. The reduce method loops through each item with a collection and produces new result to the next iteration. Each result from the last iteration ...

The <see> tag can be used to link to another class. It contains the cref member which should contain the name of the class that is to be referenced. Visual Studio will provide Intellsense when writing this tag and such references will be processed when renaming the referenced class, too. /// ...

You can use the System.IO.File.ReadAllText function to read the entire contents of a file into a string. string text = System.IO.File.ReadAllText(@"C:\MyFolder\MyTextFile.txt"); You can also read a file as an array of lines using the System.IO.File.ReadAllLines function: string[] line...

The System.IO.StreamWriter class: Implements a TextWriter for writing characters to a stream in a particular encoding. Using the WriteLine method, you can write content line-by-line to a file. Notice the use of the using keyword which makes sure the StreamWriter object is disposed as soon as ...

You can use the System.IO.File.WriteAllText function to write a string to a file. string text = "String that will be stored in the file"; System.IO.File.WriteAllText(@"C:\MyFolder\OutputFile.txt", text); You can also use the System.IO.File.WriteAllLines function which receiv...

The System.String class supports a number of methods to convert between uppercase and lowercase characters in a string. System.String.ToLowerInvariant is used to return a String object converted to lowercase. System.String.ToUpperInvariant is used to return a String object converted to upper...

Detailed instructions on getting windows-phone set up or installed.

There are two functions that can be used to obtain a readable representation of an object. repr(x) calls x.__repr__(): a representation of x. eval will usually convert the result of this function back to the original object. str(x) calls x.__str__(): a human-readable string that describes the obje...

There are two main approaches to creating a thread in Java. In essence, creating a thread is as easy as writing the code that will be executed in it. The two approaches differ in where you define that code. In Java, a thread is represented by an object - an instance of java.lang.Thread or its subcl...

A simple example of using multiple processes would be two processes (workers) that are executed separately. In the following example, two processes are started: countUp() counts 1 up, every second. countDown() counts 1 down, every second. import multiprocessing import time from random impor...

import UIKit import WebKit class ViewController: UIViewController, UISearchBarDelegate, WKNavigationDelegate, WKUIDelegate { var searchbar: UISearchBar! //All web-browsers have a search-bar. var webView: WKWebView! //The WKWebView we'll use. var toolbar: UIToolbar! //Toolb...

A file can be locked using the FileChannel API that can be acquired from Input Output streams and readers Example with streams // Open a file stream FileInputStream ios = new FileInputStream(filename); // get underlying channel FileChannel channel = ios.getChannel(); /* * t...

To ensure that our collection can be iterated using iterator or for-each loop, we have to take care of following steps: The stuff we want to iterate upon has to be Iterable and expose iterator(). Design a java.util.Iterator by overriding hasNext(), next() and remove(). I have added a simple ...

Matching an email address within a string is a hard task, because the specification defining it, the RFC2822, is complex making it hard to implement as a regex. For more details why it is not a good idea to match an email with a regex, please refer to the antipattern example when not to use a ...

Here's how to match a prefix code (a + or (00), then a number from 1 to 1939, with an optional space): This doesn't look for a valid prefix but something that might be a prefix. See the full list of prefixes (?:00|\+)?[0-9]{4} Then, as the entire phone number length is, at most, 15, we can look...

A simple example: CL-USER> (defun make-apply-twice (fun) "return a new function that applies twice the function`fun' to its argument" (lambda (x) (funcall fun (funcall fun x)))) MAKE-APPLY-TWICE CL-USER> (funcall (make-apply-twice #'1+) 3) 5 ...

Sometimes we need preserve whole model and transfer it across actions or even controllers. Storing model at session good solution for this type of requirements. If we combine this with powerful model binding features of MVC we get elegant way of doing so. We can create generic session based model bi...

Read the accelerometer Sensor with precision. This example allocates memory: void Update() { //Get Precise Accelerometer values Vector3 accelValue = preciseAccelValue(); Debug.Log("PRECISE X: " + accelValue.x + " Y: " + accelValue.y + " Z: " + acc...

Given a String containing the name of a class, it's Class object can be accessed using Class.forName: Class clazz = null; try { clazz = Class.forName("java.lang.Integer"); } catch (ClassNotFoundException ex) { throw new IllegalStateException(ex); } Java SE 1.2 It can be s...