js 实现php中sprintf函数，完成完美替换操作！

<script type="text/javascript">
//js 实现php sprintf
function sprintf(){
 var arg = arguments,
 str = arg[0] || '',
 i, n;
 for (i = 1, n = arg.length; i < n; i++) {
    str = str.replace(/%s/, arg[i]);
 }
 return str;
}
 
var string = "hello %s";
string = sprintf(string,"world");
//alert(string); //hello world!
</script>