在此页

• 描述
• 范例
• 规范
• 浏览器兼容性
• 另请参阅
• 相关话题

弃用
This feature is no longer recommended. Though some browsers might still support it, it may have already been removed from the relevant web standards, may be in the process of being dropped, or may only be kept for compatibility purposes. Avoid using it, and update existing code if possible; see the 兼容性表格 at the bottom of this page to guide your decision. Be aware that this feature may cease to work at any time.

function .caller property returns the function that invoked the specified function. It returns null for strict, async function and generator function callers.

描述

If the function f was invoked by the top level code, the value of f.caller is null , otherwise it's the function that called f . It's also null for strict, async function and generator function callers.

This property replaces the obsolete arguments.caller 特性为 arguments 对象。

The special property __caller__ , which returned the activation object of the caller thus allowing to reconstruct the stack, was removed for security reasons.

注意事项

Note that in case of recursion, you can't reconstruct the call stack using this property. Consider:

function f(n) { g(n - 1); }
function g(n) { if (n > 0) { f(n); } else { stop(); } }
f(2);
					

At the moment stop() is called the call stack will be:

f(2) -> g(1) -> f(1) -> g(0) -> stop()
					

The following is true:

stop.caller === g && f.caller === g && g.caller === f
					

so if you tried to get the stack trace in the stop() function like this:

var f = stop;
var stack = 'Stack trace:';
while (f) {
  stack += '\n' + f.name;
  f = f.caller;
}
					

the loop would never stop.

范例

Checking the value of a function's caller property

The following code checks the value a function's caller 特性。

function myFunc() {
  if (myFunc.caller == null) {
    return 'The function was called from the top!';
  } else {
    return 'This function\'s caller was ' + myFunc.caller;
  }
}
					

规范

Not part of any standard.

浏览器兼容性

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. 更新 GitHub 上的兼容性数据

	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
caller 非标	Chrome 1	Edge 12	Firefox 1	IE 8	Opera 9.6	Safari 3	WebView Android 1	Chrome Android 18	Firefox Android 4	Opera Android 10.1	Safari iOS 1	Samsung Internet Android 1.0	nodejs Yes

图例

完整支持

完整支持

非标。预期跨浏览器支持较差。

非标。预期跨浏览器支持较差。

另请参阅

• Function.name
• arguments

元数据

• 最后修改： Apr 22, 2020

相关话题

1. 标准内置对象
2. Function
3. 特性
   1. Function.arguments
   2. Function.caller
   3. Function.displayName
   4. Function.length
   5. Function.name
4. 方法
   1. Function.prototype.apply()
   2. Function.prototype.bind()
   3. Function.prototype.call()
   4. Function.prototype.toSource()
   5. Function.prototype.toString()
5. 继承：
6. Object
7. 特性
   1. Object.prototype.__proto__
   2. Object.prototype.constructor
8. 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.valueOf()
   12. Object.setPrototypeOf()