! Operator (C# Reference)

The logical negation operator (!) is a unary operator that negates its operand. It is defined for bool and returns true if and only if its operand is false.

Remarks

User-defined types can overload the ! operator (see operator).

Example

class MainClass4
{
    static void Main()
    {
        Console.WriteLine(!true);
        Console.WriteLine(!false);
    }
}
/*
Output:
False
True
*/

See Also

Reference

C# Operators

Concepts

C# Programming Guide

Other Resources

C# Reference