为什么window.location.reload需要包装在function（）{}中？ [英] Why does window.location.reload need to be wrapped in a function(){}?
问题描述
我写了一些代码来为页面添加一个按钮：
I've written some code to add a button to the page:
var myButt = document.createElement('button');
myButt.onclick = window.location.reload;
myButt.innerText = 'Reload';
document.body.appendChild(myButt);
但它会抛出错误：
TypeError：输入错误
TypeError: Type error
将其包装在一个函数中修复了问题：
Wrapping it in a function fixes the problem:
myButt.onclick = function(){ window.location.reload(); };
但我的问题是为什么前者不起作用？
But my question is why the former doesn't work?
执行 air.trace（typeof（window.location.reload））; 输出 function 。
来自高代表用户的答案表明它应该是可能的。它肯定更简洁。
An answer from a high-rep user suggests that it should be possible. It's definitely more succinct.
我正在运行Adobe AIR 3.6（运行Webkit），如果这有所不同。
I am running Adobe AIR 3.6 (which runs Webkit), if that makes a difference.
推荐答案
这个值在使用它时是不正确的。
此结果是 myButt 当你需要 window.location 。
The this value is incorrect when using it like that.
this turns out to be myButt when you need it to be window.location.
要修复此（hehe），请将其包装成您已完成的，或者绑定一个新此值：
To fix this (hehe), either wrap it as you've done, or bind a new this value to it:
myButt.onclick = window.location.reload.bind(window.location);
我刚测试过，它适用于Firefox 23.0.1。
I just tested that, and it works on Firefox 23.0.1.
为了将来参考，他使用的 Function.prototype.bind 兼容性代码 here 。
For future reference, he was using the Function.prototype.bind compatibility code found here.
with my上面的代码，他得到了错误
With my code above, he was getting the error
TypeError：在一个具有无效原型
属性的对象上调用instanceof
TypeError: instanceof called on an object with an invalid prototype property
为了解决这个问题，我将该兼容性代码的第18行更改为以下内容：
To fix this, I changed line 18 of that compatibility code to the following:
fNOP.prototype = this.prototype || {};
这样原型设置为空白对象，因为窗口.location.reload 自然没有原型。
This is so that the prototype gets set to a blank object, because window.location.reload doesn't have a prototype naturally.
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