如何在javascript函数对象中测试是否调用了无效方法？ [重复]

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Is there an equivalent of the __noSuchMethod__ feature for properties, or a way to implement it in JS? 4 answers
是否有相当于__noSuchMethod__属性的属性，或者在JS中实现它的方法？ 4个答案

Given the function object:

给定函数对象：

var foo = function foo() {
    return "My methods are bar and baz";
};
foo.bar = function () {return "ok";};
foo.prototype.baz = function () {return "ok";};

If foo.bar() or foo.baz() are called, they respond with ok. However, if I try foo.wrong(), I get an error.

如果调用foo.bar（）或foo.baz（），它们会响应ok。但是，如果我尝试foo.wrong（），我会收到错误。

Is there a way for the foo function object to respond with "Invalid method called"? In other words can I see what methods are being called within the foo function object to make sure they are valid (exist)?

有没有办法让foo函数对象响应“调用无效方法”？换句话说，我可以看到在foo函数对象中调用哪些方法以确保它们是有效的（存在）？

For example, since javascript searches the prototype chain for valid functions, is there a way to hook into that search and respond with a function of my own if the search fails (maybe a function I added to the prototype of foo to handle invalid methods)?

例如，由于javascript在原型链中搜索有效函数，如果搜索失败，有没有办法挂钩到该搜索并使用我自己的函数进行响应（可能是我添加到foo原型中以处理无效方法的函数）？

I would like to test for this situation within the foo function itself and not externaly every time I attempt to call a method of the foo function object.

我想在foo函数本身内测试这种情况，而不是每次我尝试调用foo函数对象的方法时都是externaly。

Also, please stay within strict mode guidelines.

此外，请遵守严格的模式指南。

1 个解决方案

#1

Since you don't want to check if a function exists every time you call it you can add a call function which checks the function name (as @Izzey suggested):

由于您不想在每次调用时检查函数是否存在，因此您可以添加一个检查函数名称的调用函数（如@Izzey建议的那样）：

foo.call = function(name) {
    if('function' === typeof this[name]) {
        return this[name]();
    }else{
        console.error('function not found');
    }
}

And then call each functions by using the call(name) function:

然后使用call（name）函数调用每个函数：

foo.call('bar');

#1