{{JsStatementsQLAlpha()}}
Summary
The do...while
statement 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 {{jsxref("Statements/block", "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
Example: 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.
do { i += 1; console.log(i); } while (i < 5);
Specifications
Specification | Status | Comment |
---|---|---|
ECMAScript 3rd Edition. | Standard | Initial definition. Implemented in JavaScript 1.2 |
{{SpecName('ES5.1', '#sec-12.6.1', 'do-while statement')}} | {{Spec2('ES5.1')}} | |
{{SpecName('ES6', '#sec-do-while-statement', 'do-while statement')}} | {{Spec2('ES6')}} | Trailing ; is now optional. |
Browser compatibility
{{ CompatibilityTable() }}
Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari |
---|---|---|---|---|---|
Basic support | {{ CompatVersionUnknown() }} | {{ CompatVersionUnknown() }} | IE6+ | {{ CompatVersionUnknown() }} | {{ CompatVersionUnknown() }} |
Feature | Android | Chrome for Android | Firefox Mobile (Gecko) | IE Mobile | Opera Mobile | Safari Mobile |
---|---|---|---|---|---|---|
Basic support | {{ CompatVersionUnknown() }} | {{ CompatVersionUnknown() }} | {{ CompatVersionUnknown() }} | {{ CompatVersionUnknown() }} | {{ CompatVersionUnknown() }} | {{ CompatVersionUnknown() }} |
See also
- {{jsxref("Statements/while", "while")}}
- {{jsxref("Statements/for", "for")}}