Why does this print out 10?

 

This question already has an answer here:

  • Why does ++[[]][+[]]+[+[]] return the string “10”? 8 answers

    • You can use only six different characters to write and execute any JS code. For example here are some representations to JS constructs 

    false       =>  ![]
true        =>  !![]
undefined   =>  [][[]]
NaN         =>  +[![]]
0           =>  +[]
1           =>  +!+[]
2           =>  !+[]+!+[]
10          =>  [+!+[]]+[+[]]
Array       =>  []
Number      =>  +[]
String      =>  []+[]
Boolean     =>  ![]
Function    =>  []["filter"]
eval        =>  []["filter"]["constructor"]( CODE )()
window      =>  []["filter"]["constructor"]("return this")()

    Proof at JS F*ck and detail at Why does ++[[]][+[]]+[+[]] return the string "10"?

    链接地址: http://www.djcxy.com/p/48052.html

    上一篇: 为什么alert（++ [[]] [+ []] + [+ []]）; 打印10？

    下一篇: 为什么打印出10张？