Map.prototype.clear() - JavaScript 编辑

The clear() method removes all elements from a Map object.

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The source for this interactive example is stored in a GitHub repository. If you'd like to contribute to the interactive examples project, please clone https://github.com/mdn/interactive-examples and send us a pull request.

Syntax

myMap.clear();

Return value

undefined.

Examples

Using clear()

var myMap = new Map();
myMap.set('bar', 'baz');
myMap.set(1, 'foo');

myMap.size;       // 2
myMap.has('bar'); // true

myMap.clear();

myMap.size;       // 0
myMap.has('bar')  // false

Specifications

Specification
ECMAScript (ECMA-262) The definition of 'Map.prototype.clear' in that specification.

Browser compatibility

BCD tables only load in the browser

See also

• Map