為什么var?x?=?1;
function?foo(x?=?x)?{
??//?...
}
foo()?//x?is?not?defined會(huì)報(bào)錯(cuò)，而var?x?=?1;
function?f(y?=?x)?{
??console.log(y);
}
f() //1就能得出結(jié)果１呢
ＥＳ６的問(wèn)題
牛奶老哥哥
2017-05-26 11:20:35
