C# tutorial-Conditional statements-if else

C# conditional statements-if/else

-if/else statement

if statement without else:

if (condition) {

    Statement

    Statement

}

Or

if statement with else: 

if (condition) {

  Statement

  Statement

}

else {

  Statement

  Statement

}

      Or

if (condition) {

  Statement

  Statement

}

else if {

  Statement

  Statement

}

else {

   Statement

   Statement

}

Example:

int age;
Console.WriteLine("Enter your age:");
age=int.Parse(Console.ReadLine());
if (age >= 18)
   Console.WriteLine("You can play the game.");

   else Console.WriteLine("You are not allowed to play the game.");

The below table is the list of operators which can be used in if/else statement.

If you want to put more than one statements in an if/else statement then you must write them in brackets.

Example:

int age;
Console.WriteLine("Enter your age:");
age=int.Parse(Console.ReadLine());
if (age == 18)
{
   Console.WriteLine("You are 18 years old.");
   Console.WriteLine("You are allowed to play the game.");
}

Note: if/else statements can be nested.

Example:

string user, password;
Console.WriteLine("Enter username:");
user=Console.ReadLine();
Console.WriteLine("Enter password:");
password=Console.ReadLine();
if (user =="dara")
   if (password == "12345")
      Console.WriteLine("Welcome{0,8}!",user);

   else Console.WriteLine("Invalid password! Try again");

else Console.WriteLine("Invalid user name! Try again");

 If you want to evaluate more than one condition you can use many else if blocks as possible.

Example:

   Console.WriteLine("Enter a letter:");

      char c =(char)Console.Read();

      if (Char.IsDigit(c)==true)

         Console.WriteLine("A number");

      else if(char.IsLower(c)==true)

         Console.WriteLine("A lower case letter");

      else if(char.IsUpper(c)==true)