如何JavaScript 数组变random？

Question

有数组:
var arr1 = ["a", "b", "c", "d"];
怎样才能变得random？

Answer 1

<script type="text/javascript"> 
//随机取得数组中的一个 
var Arr = ["a","b","c","d"];  
var n = Math.floor(Math.random() * Arr.length + 1)-1;  
alert(Arr[n]);  
</script>