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.
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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
blockstatement ({ ... }) to group those statements.
condition- An expression evaluated after each pass through the loop. If
conditionevaluates to true, thestatementis re-executed. Whenconditionevaluates 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.
HTML content
<div id="example"></div>
JavaScript content
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
document.getElementById('example').innerHTML = result;
Result
Specifications
| Specification |
|---|
| ECMAScript Latest Draft (ECMA-262) The definition of 'do-while statement' in that specification. |
Browser compatibility
The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
Update compatibility data on GitHub
| Desktop | Mobile | Server | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
do...while | Chrome Full support 1 | Edge Full support 12 | Firefox Full support 1 | IE Full support 4 | Opera Full support Yes | Safari Full support 1 | WebView Android Full support 1 | Chrome Android Full support 18 | Firefox Android Full support 4 | Opera Android Full support Yes | Safari iOS Full support 1 | Samsung Internet Android Full support 1.0 | nodejs Full support Yes |
Legend
- Full support
- Full support