直接上代码

<script type="text/javascript">
    var url = "http://www.***.com/n/2013/01/08/1037962.shtml";
    //url = "http://www.***.com/mine/mine_show.aspx?id=1037962";
    var reg = /\/\d+.shtml|\?id\=\d+/gi;
    var result;
    if((result = reg.exec(url)) != null){
        result += "";
        var id = result.match(/\d+/g);
        alert(id);
    }
</script>

参考文章

http://www.w3school.com.cn/js/jsref_obj_regexp.asp

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下面的两条语句是等价的： 
re = new RegExp("\\w+","gi") 
re = /\w+/gi