“你知道吗? 在js里面 undefined是一个类型,也是一个值,甚至还是一个char数组,比如var a = undefined 于是a[1] 的值就是n。”
var a = undefined undefined a[1] VM205:2 Uncaught TypeError: Cannot read property '1' of undefined at <anonymous>:2:2 at Object.InjectedScript._evaluateOn (<anonymous>:905:140) at Object.InjectedScript._evaluateAndWrap (<anonymous>:838:34) at Object.InjectedScript.evaluate (<anonymous>:694:21)(anonymous function) @ VM205:2InjectedScript._evaluateOn @ VM145:905InjectedScript._evaluateAndWrap @ VM145:838InjectedScript.evaluate @ VM145:694