Microsoft® JScript™
++ and -- Operators
 Language Reference 
Version 1 

See Also


Description
Used to increment or decrement a variable by one.
Syntax 1
result = ++variable
result = --variable
result = variable++
result = variable--
Syntax 2
++variable
--variable
variable++
variable--

The syntax of the ++ and -- operators has these parts:

Part Description
result Any variable.
variable Any variable.

Remarks
The increment and decrement operators are used as a shortcut to modify the value stored in a variable. The value of an expression containing one of these operators depends on whether the operator comes before or after the variable:
var j, k;
k = 2;
j = ++k;
j is assigned the value 3, as the increment occurs before the expression is evaluated.

Contrast the following example:

var j, k;
k = 2;
j = k++;
Here, j is assigned the value 2, as the increment occurs after the expression is evaluated.