js中含有变量的replace怎么写的?

Question

<script type="text/javascript">
var fendata="9,45|4,12|9,21|";
var pid='9'; 
var rstr =new RegExp("/"+pid+",\d{1,2}\\|/","g");
alert(rstr);
alert(fendata.replace(rstr,''));
alert(fendata);
</script>这样的也不行.

Answer 1

<script type="text/javascript">
var fendata="9,45|4,12|9,21|";
var pid='9'; 
var rstr =new RegExp(""+pid+",[0-9]{1,2}[\|]+","g");
alert(rstr);    
alert(fendata.replace(rstr,''));
alert(fendata);            
</script>

Answer 2

<script type="text/javascript">
var fendata="9,45|4,12|9,21|";
var pid='9'; 
var rstr =new RegExp(pid+",\\d{1,2}\\|","g");
alert(rstr);    
alert(fendata.replace(rstr,''));
alert(fendata);            
</script>这样就可以了，要多个子＼