Let us see an example of a list collection.We have set the elements −List list = new List(); list.Add(20); list.Add(40); list.Add(60); list.Add(80);Now let’s say we need to retrieve the first element from the list. For that, set the index like this −int a = list[0];The following is an example showing how to retrieve elements from a list collection −Exampleusing System; using System.Collections.Generic; class Demo {    static void Main(String[] args) {       List list = new List();       list.Add(20);       list.Add(40);       list.Add(60);       list.Add(80);     ... Read More

The return statement is used to return value. When a program calls a function, the program control is transferred to the called function.The following is an example to learn about the usage of return statement in C#. Here, we are finding the average and returning the result using the return statement.double getAverage(int[] arr, int size) {    int i;    double avg;    int sum = 0;    for (i = 0; i < size; ++i) {       sum += arr[i];    }    avg = (double)sum / size;    return avg; }Here is the complete ... Read More

String LiteralsString literals or constants are enclosed in double quotes "" or with @"". A string contains characters that are similar to character literals: plain characters, escape sequences, and universal characters.Here are some examples of String Literals −Hello, World" "Welcome, \The following is an example showing the usage of string literals −Exampleusing System; namespace Demo {    class Program {       static void Main(string[] args) {          // string          string str1 ="Hello, World";          Console.WriteLine(str1);          // Multi-line string   ... Read More

Use the static method String.Format for form double string format in C#.For three decimal places −String.Format("{0:0.000}", 987.383); String.Format("{0:0.000}", 987.38); String.Format("{0:0.000}", 987.7899);For thousands separator −String.Format("{0:0,0.0}", 54567.46); String.Format("{0:0,0}", 54567.46);To format string −Exampleusing System; class Demo {    public static void Main(String[] args) {       Console.WriteLine("Three decimal places...");           Console.WriteLine( String.Format("{0:0.000}", 987.383));       Console.WriteLine( String.Format("{0:0.000}", 987.38));       Console.WriteLine(String.Format("{0:0.000}", 987.7899));           Console.WriteLine("Thousands Separator...");       Console.WriteLine(String.Format("{0:0,0.0}", 54567.46));       Console.WriteLine(String.Format("{0:0,0}", 54567.46));    } }

Declare a member function as static. Such functions can access only static variables. The static functions exist even before the object is created.A static class cannot be instantiated and can only contain static members.Static methods is set using static keyword −public static int getNum() {    return num; }The following example demonstrates the use of static and non-static methods −Exampleusing System; namespace StaticVarApplication {    class StaticVar {       public static int num;       public void count() {          num++;       }       public static int ... Read More

To swap two variables in a single line using the Bitwise XOR Operator.val1 = val1 ^ val2 ^ (val2 = val1);Above, we have set the values −int val1 = 30; int val2 = 60;The following is the example to swap both the variable in one line using C# −Exampleusing System; class Demo {    public static void Main(String[] args) {       int val1 = 30;       int val2 = 60;       Console.WriteLine("Values before swap");       Console.WriteLine(val1);       Console.WriteLine(val2);       val1 = val1 ^ val2 ^ (val2 = val1);       Console.WriteLine("Values after swap");       Console.WriteLine(val1);       Console.WriteLine(val2);    } }

To swap two strings without using a temp variable, you can try the following code and logic.Append the second string with the first.str1 = str1 + str2;Set the str1 in str2.str2 = str1.Substring(0, str1.Length - str2.Length);Now, the final step is to set str2 in str1 −str1 = str1.Substring(str2.Length);Exampleusing System; class Demo {    public static void Main(String[] args) {       String str1 = "Brad";       String str2 = "Pitt";       Console.WriteLine("Strings before swap");       Console.WriteLine(str1);       Console.WriteLine(str2);       str1 = str1 + str2; ... Read More

Task represents an asynchronous operation in C#. The following states how you can start a task in C#.Use a delegate to start a task.Task t = new Task(delegate { PrintMessage(); }); t.Start();Use Task Factory to start a task.Task.Factory.StartNew(() => {Console.WriteLine("Welcome!"); });You can also use Lambda.Task t = new Task( () => PrintMessage() ); t.Start();The most basic way to start a task is using the run().Exampleusing System; using System.Threading.Tasks; public class Example {    public static void Main() {       Task task = Task.Run( () => {          int a = 0;          for (a = 0; a

The namespace used to set a timer is System. Timers. The Timer class generates an event after a set interval, with an option to generate recurring events.Firstly, create a timer object for 5 seconds interval −timer = new System.Timers.Timer(5000);Set elapsed event for the timer. This occurs when the interval elapses −timer.Elapsed += OnTimedEvent;Now start the timer.timer.Enabled = true;Exampleusing System; using System.Timers; public class Demo {    private static Timer timer;    public static void Main() {       timer = new System.Timers.Timer();       timer.Interval = 5000;       timer.Elapsed += OnTimedEvent;     ... Read More

A try block identifies a block of code for which particular exceptions is activated. It is followed by one or more catch blocks.try { }With that, you need to set catch statement as well to catch the exception −try {       // statements causing exception    } catch( ExceptionName e1 ) {       // error handling code    }The following is an example −Exampleclass Demo {    int result;    Demo() {       result = 0;    }    public void division(int val1, int val2) {       try {   ... Read More