do...while
The do...while
creates a loop that executes a specified statement until the test condition evaluates to false. The condition is evaluated after executing the statement, resulting in the specified statement executing at least once.
Syntax
do statement while (condition);
statement
-
A statement that is executed at least once and is re-executed each time the condition evaluates to true. To execute multiple statements within the loop, use a block statement (
{ ... }
) to group those statements. condition
-
An expression evaluated after each pass through the loop. If
condition
evaluates to true, thestatement
is re-executed. Whencondition
evaluates to false, control passes to the statement following thedo...while
.
Examples
Using do...while
In the following example, the do...while
loop iterates at least once and reiterates until i
is no longer less than 5.
var result = ''; var i = 0; do { i += 1; result += i + ' '; } while (i > 0 && i < 5); // Despite i == 0 this will still loop as it starts off without the test console.log(result);
Specifications
Browser compatibility
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Chrome | Edge | Firefox | Internet Explorer | Opera | Safari | WebView Android | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | |
do...while |
1 |
12 |
1 |
4 |
4 |
1 |
1 |
18 |
4 |
10.1 |
1 |
1.0 |
See also
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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/do...while