JS

1. JSFuck

1.1. encode

jsfuck.com

1.2. decode

chrome(firefox) console input follow

alert(/.+(?=\n})/.exec(eval(prompt().slice(0,-2))))

or

alert(/\n(.+)/.exec(eval(prompt().slice(0,-2)))[1])

运行，然后在弹出框中输入 jsfuck 编码的代码，即可得到解码后的代码

解析：

alert(
    /\n(.+)/.exec(                 // regex to extract code from inside outer function braces {}
        eval(prompt().slice(0,-2)) // remove the final set of parens () and evaluate the code
                                   // this results in a function, which will be converted to a string as 'exec' expects a string
    )[1]                           // get the first capture group
)