for Statement

Microsoft® JScript™
for Statement
Language Reference
Version 1

Description

Executes a block of statements for as long as a specified condition is true.

Syntax

for (initialization; test; increment)
statement
The for statement syntax has these parts:

Part Description

initialization An expression. This expression is executed only once, before the loop is executed.

test A Boolean expression. If test is true, statement is executed. If test if false, the loop is terminated.

increment An expression. The increment expression is executed at the end of every pass through the loop.

statement The statement to be executed if test is true. Can be a compound statement.

Remarks

You usually use a for loop when the loop is to be executed a specific number of times. The following example demonstrates one.
for (var i = 0; i < 10; ++i) {
  console.log("i is ("+i+")");                
}
See the continue Statement. This is especially useful in combination with the Label Statement. Example:
forLoop1: //The first for statement is labeled "forLoop1"
for (i = 0; i < 3; ++i) {      
   forLoop2: //The second for statement is labeled "forLoop2"
   for (j = 0; j < 3; ++j) {   
      if (i === 1 && j === 1) {
         continue forLoop1
      }
      console.log('i = ' + i + ', j = ' + j)
   }
}
// 'i = 1, j - 1' will NOT print, all other combinations from 0 to 2 will.

Part	Description
initialization	An expression. This expression is executed only once, before the loop is executed.
test	A Boolean expression. If test is true, statement is executed. If test if false, the loop is terminated.
increment	An expression. The increment expression is executed at the end of every pass through the loop.
statement	The statement to be executed if test is true. Can be a compound statement.