Boolean.prototype.valueOf()

valueOf() 方法返回一个Boolean对象的原始值。

语法

bool.valueOf()

返回值

给定Boolean对象的原始值

描述

Boolean字面量的原始值作为布尔数据类型。

该方法通常在 JavaScript 内部调用，而不是在代码中显式调用。

示例

使用 valueOf

x = new Boolean();
myVar = x.valueOf()      // assigns false to myVar

规范

Specification Status Comment
ECMAScript 1st Edition (ECMA-262) Standard Initial definition. Implemented in JavaScript 1.1.
ECMAScript 5.1 (ECMA-262)
Boolean.prototype.valueOf		 Standard  
ECMAScript 2015 (6th Edition, ECMA-262)
Boolean.prototype.valueOf		 Standard  
ECMAScript Latest Draft (ECMA-262)
Boolean.prototype.valueOf		 Draft  

浏览器兼容

Update compatibility data on GitHub
Desktop Mobile Server
Chrome Edge Firefox Internet Explorer Opera Safari Android webview Chrome for Android Firefox for Android Opera for Android Safari on iOS Samsung Internet Node.js
valueOf Chrome Full support 1 Edge Full support 12 Firefox Full support 1 IE Full support 4 Opera Full support Yes Safari Full support Yes WebView Android Full support 1 Chrome Android Full support 18 Firefox Android Full support 4 Opera Android Full support Yes Safari iOS Full support Yes Samsung Internet Android Full support 1.0 nodejs Full support Yes

Legend

Full support  
Full support

相关链接

  1. JavaScript 标准库
  2. Boolean
  3. 属性
    1. Boolean.prototype
  4. 方法
    1. Boolean.prototype.toSource()
    2. Boolean.prototype.toString()
    3. Boolean.prototype.valueOf()
  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.name
    7. Function.prototype
  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()