Set.prototype.clear()

clear() 方法用来清空一个 Set 对象中的所有元素。

语法

mySet.clear();

返回值

undefined.

示例

var mySet = new Set();
mySet.add(1);
mySet.add("foo");

mySet.size;       // 2
mySet.has("foo"); // true

mySet.clear();

mySet.size;       // 0
mySet.has("bar")  // false

规范

Specification Status Comment
ECMAScript 2015 (6th Edition, ECMA-262)
Set.prototype.clear		 Standard Initial definition.
ECMAScript Latest Draft (ECMA-262)
Set.prototype.clear		 Draft  

浏览器兼容性

We're converting our compatibility data into a machine-readable JSON format. This compatibility table still uses the old format, because we haven't yet converted the data it contains. Find out how you can help!

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
Basic support 38 19.0 (19.0) 11 25 7.1
Feature Android Chrome for Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support 未实现 25 19.0 (19.0) 未实现 未实现 8

相关链接

  1. JavaScript 标准库
  2. Set
  3. 属性
    1. Set.prototype
    2. Set.prototype.size
    3. get Set[@@species]
  4. 方法
    1. Set.prototype.add()
    2. Set.prototype.clear()
    3. Set.prototype.delete()
    4. Set.prototype.entries()
    5. Set.prototype.forEach()
    6. Set.prototype.has()
    7. Set.prototype.values()
    8. Set.prototype[@@iterator]()
  5. 继承
  6. Function
  7. 属性
    1. Function.arguments
    2. Function.arity
    3. Function.caller
    4. Function.displayName
    5. Function.length
    6. Function.prototype
    7. Function.name
  8. 方法
    1. Function.prototype.apply()
    2. Function.prototype.bind()
    3. Function.prototype.call()
    4. Function.prototype.isGenerator()
    5. Function.prototype.toSource()
    6. Function.prototype.toString()
  9. Object
  10. 属性
    1. Object.prototype.__count__
    2. Object.prototype.__noSuchMethod__
    3. Object.prototype.__parent__
    4. Object.prototype.__proto__
    5. Object.prototype.constructor
  11. 方法
    1. Object.prototype.__defineGetter__()
    2. Object.prototype.__defineSetter__()
    3. Object.prototype.__lookupGetter__()
    4. Object.prototype.__lookupSetter__()
    5. Object.prototype.hasOwnProperty()
    6. Object.prototype.isPrototypeOf()
    7. Object.prototype.propertyIsEnumerable()
    8. Object.prototype.toLocaleString()
    9. Object.prototype.toSource()
    10. Object.prototype.toString()
    11. Object.prototype.unwatch()
    12. Object.prototype.valueOf()
    13. Object.prototype.watch()
    14. Object.setPrototypeOf()