C# - Logical Operators

Following table shows all the logical operators supported by C#. Assume variable A holds Boolean value true and variable B holds Boolean value false, then −

Operator	Description	Example
&&	Called Logical AND operator. If both the operands are non zero then condition becomes true.	(A && B) is false.
\|\|	Called Logical OR Operator. If any of the two operands is non zero then condition becomes true.	(A \|\| B) is true.
!	Called Logical NOT Operator. Use to reverses the logical state of its operand. If a condition is true then Logical NOT operator will make false.	!(A && B) is true.

Example

The following example demonstrates all the logical operators available in C# −

Live Demo

using System;

namespace OperatorsAppl {
   class Program {
      static void Main(string[] args) {
         bool a = true; 
         bool b = true;
         
         if (a && b) {
            Console.WriteLine("Line 1 - Condition is true");
         }
         
         if (a || b) {
            Console.WriteLine("Line 2 - Condition is true");
         }
         
         /* lets change the value of  a and b */
         a = false;
         b = true;
         
         if (a && b) {
            Console.WriteLine("Line 3 - Condition is true");
         } else {
            Console.WriteLine("Line 3 - Condition is not true");
         }
         
         if (!(a && b)) {
            Console.WriteLine("Line 4 - Condition is true");
         }
         Console.ReadLine();
      }
   }
}

When the above code is compiled and executed, it produces the following result −

Line 1 - Condition is true
Line 2 - Condition is true
Line 3 - Condition is not true
Line 4 - Condition is true

csharp_operators.htm