Home - News ( United States | United Kingdom | Italy | Germany ) - Football scores

Showing content from http://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Errors/Called_on_incompatible_type below:

X.prototype.y called on incompatible type - JavaScript

TypeError: Function.prototype.toString called on incompatible object (Firefox)
TypeError: Function.prototype.bind called on incompatible target (Firefox)
TypeError: Method Set.prototype.add called on incompatible receiver undefined (Chrome)
TypeError: Bind must be called on a function (Chrome)

当这个错误被抛出时，属于某个对象的函数被调用，但是没有提供给 this 与其所期望的函数类型一致的参数。

在调用 Function.prototype.call() 或Function.prototype.apply() 方法，但是为 this 提供的绑定对象与预期的不匹配时，这个问题就会出现。

该问题还会出现于将一个（存储在一个对象中的）函数提供给另外一个函数作为参数时。在这种情况下，函数所在的对象并非该函数的 this 绑定的目标对象。为了解决这个问题，你或者为其提供一个 lambda 表达式，该表达式完成函数要完成的任务，或者调用 Function.prototype.bind() 函数为 this 强制绑定期望的对象。

var mySet = new Set();
["bar", "baz"].forEach(mySet.add);
// mySet.add is a function, but "mySet" is not captured as this.

var myFun = function () {};
["bar", "baz"].forEach(myFun.bind);
// myFun.bind is a function, but "myFun" is not captured as this.

var mySet = new Set();
["bar", "baz"].forEach(mySet.add.bind(mySet));
// This works due to binding "mySet" as this.

var myFun = function () {};
["bar", "baz"].forEach((x) => myFun.bind(x));
// This works using the "bind" function. It creates a lambda forwarding the argument.

RetroSearch is an open source project built by @garambo | Open a GitHub Issue

Search and Browse the WWW like it's 1997 | Search results from DuckDuckGo

HTML: 3.2 | Encoding: UTF-8 | Version: 0.7.4