为什么这会导致 Chrome 出现无限循环？
这可能是一个愚蠢的问题，但为什么下面的 for 循环在 Chrome 中会进入无限循环，而在 Firefox 中却不会？ （显然，循环测试是失败的地方 - 我只是不知道为什么）。
for(var i = 0; localStorage[this.config.localStoragePrefix + i] != 'undefined'; i++)
this.config.appCount++;
它正在检查存在多少 localStorage 元素。例如：
localStorage['myPrefix_0']
localStorage['myPrefix_1']
localStorage['myPrefix_2'] ...
会返回 3。
对于为什么这个在 Chrome 中永远循环有什么想法吗？
This may be a dumb question, but why is the below for loop going into an endless loop in Chrome but not in Firefox? (Obviously, the loop test is where it's failing - I just don't know why).
for(var i = 0; localStorage[this.config.localStoragePrefix + i] != 'undefined'; i++)
this.config.appCount++;
It's doing checking how many localStorage elements exist. For example:
localStorage['myPrefix_0']
localStorage['myPrefix_1']
localStorage['myPrefix_2'] ...
Would return 3.
Any thoughts on why this loops forever in Chrome?
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这是因为您将其与 undefined 的字符串表示形式进行比较，而不是 undefined 本身：
因此您有两个选择，您可以
1)
typeof localStorage['asdf'] != "undefined"或
2 )
localStorage['asdf'] != 未定义This is because you are comparing it to the string representation of undefined, rather than undefined itself:
So you have two options, you can
1)
typeof localStorage['asdf'] != "undefined"or
2)
localStorage['asdf'] != undefinedlocalStorage[this.config.localStoragePrefix + i] != 'undefined'始终返回 true，因为您正在与 'undefined' 字符串进行比较。更改为undefined原语或使用typeof进行测试localStorage[this.config.localStoragePrefix + i] != 'undefined'always returns true, as you're comparing to 'undefined' string. Change to toundefinedprimitive or test usingtypeof这是因为“未定义”与未定义不同：P
it's because 'undefined' is different then undefined :P