The first form is a prefix increment operation. The result of the operation is the value of the operand after it has been incremented.

The second form is a postfix increment operation. The result of the operation is the value of the operand before it has been incremented.

Numeric and enumeration types have predefined increment operators. User-defined types can overload the ++ operator. Operations on integral types are generally allowed on enumeration.

// cs_operator_increment.cs
using System;
class MainClass
{
    static void Main() 
    {
        double x;
        x = 1.5;
        Console.WriteLine(++x);
        x = 1.5;
        Console.WriteLine(x++);
        Console.WriteLine(x);
    }
}

Output

2.5
1.5
2.5

Reference

Concepts

Other Resources