while Statement (JavaScript)

expression

Required. A Boolean expression that is checked before each iteration of the loop. If expression is true, the loop is executed. If expression is false, the loop is terminated.

statements

Optional. One or more statements to be executed if expression is true.

The while statement checks expression before a loop is first executed. If expression is false at this time, the loop is never executed.

The following example illustrates the use of the while statement.

var i = 0;
var j = 10;
while (i < 100) {
    if (i == j)
        break;
    i++;
}
document.write(i);

// Output: 10

Supported in the following document modes: Quirks, Internet Explorer 6 standards, Internet Explorer 7 standards, Internet Explorer 8 standards, Internet Explorer 9 standards, Internet Explorer 10 standards. Also supported in Windows Store apps. See Version Information.

Reference