获取页面的全局变量

Question

页面中的全局变量很多，
arr=["a","b","n","m","r","t","w","q","s","o","j","k","us","regTime","uvel","usFirst","success","user","first","Center","detail","detailType",....]
总之，要判断的很多。。加入页面中有全局变量了，例如var a="123";var b="456";那么就alert变量值，没有的话什么也不做

Answer 1

for(var i in arr) {
   var bool = eval("typeof " + arr[i] + " != 'undefined'");
   if(bool) {
       alert(eval("(" + arr[i] + ")"));
   }
}
是这个意思么。。

Answer 2

<script type="text/javascript">
arr=["a","b","n","m","r","t","w","q","s","o","j","k","us","regTime","uvel","usFirst","success","user","first","Center","detail","detailType"];
var a="123";
var b="456";
for(var i in arr){
if(window[arr[i]]){
alert(window[arr[i]]);
}
}
</script>
这样？