推荐回答(1个)
首先你要有一个观念
JS, 除非作者自己搞了一个类似於解释器的东西, 否则所有的加密的最後一步都是eval
所以对於没有把eval转义的加密来讲
比如你给出的那个, 直接蒐索eval然後把它删去再复制到你的console直接执行就能还原
然而如果你并不清楚你所操作的代码的加密方式
或者eval也被转义了
那麽就需要借助工具来明确结构了
这里我使用的是Uglify, 他会把所有变量名压缩, 把类似'\xff'等的转义还原, 生成等价代码
首先是压缩

压缩的结果

然後格式化

如果你对JSPacker比较熟悉
那麽看到eval(function(a, b, c, d, e, f)基本就知道它怎麽来的了
当然对於不同的加密方式还得具体分析, 但你只要见得多了基本都能解密
Uglify, JSPacker, 格式化等工具都是要麽开源要麽你可以自行部署的
当然如果你只是有一两个文件要解码你也可以使用在线工具
这类工具非常多, 我使用的是tool.css-js.com
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