function aa(){ var aaa="123"; } aa(); alert (typeof aa.aaa)=undefined???
为什么是undefined?为什么不是string?
function aa(){ var aaa="123"; } aa(); alert (typeof aa.aaa)=undefined???
为什么是undefined?为什么不是string?
aaa是aa的私有变量,外部访问不到,而且你这样调用是将aaa当做aa的属性了,aa又没有这个属性当然是undefined
function aa() { var aaa = "123"; return aaa}
aa.aaa = '123';
alert(aa());
alert(typeof aa.aaa)