The break statement terminates the current loop, switch, or label statement and transfers program control to the statement following the terminated statement.
Syntax
break [label];
label- Optional. Identifier associated with the label of the statement. If the statement is not a loop or
switch, this is required.
Description
The break statement includes an optional label that allows the program to break out of a labeled statement. The break statement needs to be nested within the referenced label. The labeled statement can be any block statement; it does not have to be preceded by a loop statement.
Examples
The following function has a break statement that terminates the while loop when i is 3, and then returns the value 3 * x.
function testBreak(x) {
var i = 0;
while (i < 6) {
if (i == 3) {
break;
}
i += 1;
}
return i * x;
}
The following code uses break statements with labeled blocks. A break statement must be nested within any label it references. Notice that inner_block is nested within outer_block.
outer_block: {
inner_block: {
console.log('1');
break outer_block; // breaks out of both inner_block and outer_block
console.log(':-('); // skipped
}
console.log('2'); // skipped
}
The following code also uses break statements with labeled blocks but generates a Syntax Error because its break statement is within block_1 but references block_2. A break statement must always be nested within any label it references.
block_1: {
console.log('1');
break block_2; // SyntaxError: label not found
}
block_2: {
console.log('2');
}
Specifications
| Specification | Status | Comment |
|---|---|---|
| ECMAScript 1st Edition | Standard | Initial definition. Unlabeled version. |
| ECMAScript 3rd Edition | Standard | Labeled version added. |
| ECMAScript 5.1 (ECMA-262) The definition of 'Break statement' in that specification. |
Standard | |
| ECMAScript 6 (ECMA-262) The definition of 'Break statement' in that specification. |
Release Candidate |
Browser compatibility
| Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari |
|---|---|---|---|---|---|
| Basic support | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) |
| Feature | Android | Chrome for Android | Firefox Mobile (Gecko) | IE Mobile | Opera Mobile | Safari Mobile |
|---|---|---|---|---|---|---|
| Basic support | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) |