这种js计算该解析？ !+[]+!![]+!![]

yeksama 2018-09-12 09:29:52

写个爬虫遇到个cookie验证，这串代码计算后得出来的结果就是cookie值了。
大佬们，这都啥意思？怎么算出来的？

(!+[]+!![]+!![]+!![]+!![]+!![]+[])+(!+[]+!![]+!![]+!![]+!![]+!![]+!![]+!![]+!![]+[])+(+!![]+[])+(!+[]+!![]+!![]+!![]+!![]+!![]+!![]+!![]+!![]+[])+(!+[]+!![]+!![]+!![]+!![]+[])+(+!![]+[])+(!+[]+!![]+[])+(!+[]+!![]+!![]+!![]+!![]+!![]+!![]+!![]+!![]+[])+(!+[]+!![]+!![]+[])+(![]+[])[+[]]+(!+[]+!![]+!![]+!![]+!![]+!![]+!![]+!![]+[])+([]+{})[!+[]+!![]]+(!+[]+!![]+!![]+!![]+!![]+[])+(+[]+[])+([]+{})[!+[]+!![]+!![]+!![]+!![]]+(!+[]+!![]+!![]+!![]+!![]+!![]+!![]+!![]+[])+(!+[]+!![]+!![]+!![]+!![]+!![]+!![]+!![]+!![]+[])+(+[]+[])+(!+[]+!![]+!![]+[])+(+[]+[])+([]+{})[!+[]+!![]]+([][[]]+[])[!+[]+!![]]+(!+[]+!![]+!![]+!![]+!![]+!![]+!![]+!![]+!![]+[])+([][[]]+[])[!+[]+!![]+!![]]+(+!![]+[])+([][[]]+[])[!+[]+!![]+!![]]+(!+[]+!![]+!![]+!![]+!![]+[])+(+!![]+[])+(!+[]+!![]+!![]+!![]+!![]+!![]+!![]+[])+(!+[]+!![]+[])+([][[]]+[])[!+[]+!![]+!![]]+(+{}+[])[+!![]]+(!+[]+!![]+!![]+!![]+!![]+!![]+[])+(!+[]+!![]+!![]+[])+(!+[]+!![]+!![]+!![]+!![]+[])+([][[]]+[])[!+[]+!![]+!![]]+([]+{})[!+[]+!![]]+(!+[]+!![]+!![]+!![]+!![]+!![]+!![]+!![]+!![]+[])+(!+[]+!![]+!![]+!![]+!![]+[])+(![]+[])[+[]]+(![]+[])[+[]]+(!+[]+!![]+!![]+!![]+[])+(!+[]+!![]+!![]+!![]+!![]+!![]+!![]+[])+(![]+[])[+[]]+(!+[]+!![]+[])+(!+[]+!![]+!![]+[])+(!+[]+!![]+[])+(!+[]+!![]+!![]+!![]+!![]+!![]+!![]+!![]+[])+(!+[]+!![]+!![]+!![]+!![]+!![]+!![]+[])+(!+[]+!![]+!![]+!![]+!![]+!![]+!![]+!![]+!![]+[])+(!+[]+!![]+!![]+!![]+!![]+!![]+!![]+!![]+[])+(!+[]+!![]+!![]+[])+(!+[]+!![]+!![]+!![]+!![]+!![]+!![]+!![]+!![]+[])+([][[]]+[])[!+[]+!![]]+(!+[]+!![]+!![]+[])+([]+{})[!+[]+!![]]+(!+[]+!![]+!![]+!![]+!![]+[])+(!+[]+!![]+!![]+!![]+[])+(![]+[])[+[]]+(+{}+[])[+!![]]+(![]+[])[+[]]+(!+[]+!![]+!![]+!![]+!![]+!![]+!![]+!![]+!![]+[])+(+{}+[])[+!![]]+(!+[]+!![]+!![]+!![]+!![]+[])

google搜索了下搜到源码。



    $_object_Object = "[]+{}";

    $_NaN = "+{}+[]";

    $_true = "!![]+[]";

    $_false = "![]+[]";

    $_undefined = "[][[]]+[]";



    $characters["0"] = "+[]";

    $characters["1"] = "+!![]";

    $characters["2"] = "!+[]+!![]";

    $characters["3"] = "!+[]+!![]+!![]";

    $characters["4"] = "!+[]+!![]+!![]+!![]";

    $characters["5"] = "!+[]+!![]+!![]+!![]+!![]";

    $characters["6"] = "!+[]+!![]+!![]+!![]+!![]+!![]";

    $characters["7"] = "!+[]+!![]+!![]+!![]+!![]+!![]+!![]";

    $characters["8"] = "!+[]+!![]+!![]+!![]+!![]+!![]+!![]+!![]";

    $characters["9"] = "!+[]+!![]+!![]+!![]+!![]+!![]+!![]+!![]+!![]";

    $characters[" "] = "(" . $_object_Object . ")[" . $characters['7']  . "]";

    $characters["["] = "(" . $_object_Object . ")[" . $characters['0']  . "]";

    $characters["]"] = "(" . $_object_Object . ")[" .  $characters['1'] . "+" . $characters['4'] . "]";

    $characters["a"] = "(" . $_NaN . ")[" . $characters['1'] . "]";

    $characters["b"] = "(" . $_object_Object . ")[" . $characters['2'] . "]";

    $characters["c"] = "(" . $_object_Object . ")[" . $characters['5'] . "]";

    $characters["d"] = "(" . $_undefined . ")[" . $characters['2'] . "]";

    $characters["e"] = "(" . $_undefined . ")[" . $characters['3'] . "]";

    $characters["f"] = "(" . $_false . ")[" . $characters['0'] . "]";

    $characters["i"] = "(" . $_undefined . ")[" . $characters['5'] . "]";

    $characters["j"] = "(" . $_object_Object . ")[" . $characters['3'] . "]";

    $characters["l"] = "(" . $_false . ")[" . $characters['2'] . "]";

    $characters["n"] = "(" . $_undefined . ")[" . $characters['1'] . "]";

    $characters["o"] = "(" . $_object_Object . ")[" . $characters['1'] . "]";

    $characters["r"] = "(" . $_true . ")[" . $characters['1'] . "]";

    $characters["s"] = "(" . $_false . ")[" . $characters['3'] . "]";

    $characters["t"] = "(" . $_true . ")[" . $characters['0'] . "]";

    $characters["u"] = "(" . $_undefined . ")[" . $characters['0'] . "]";

    $characters["N"] = "(" . $_NaN . ")[" . $characters['0'] . "]";

    $characters["O"] = "(" . $_object_Object . ")[" . $characters['8'] . "]";