<script type="text/javascript">
  <!--
    function MoneyCheck(){
        var isNum = /^\d+(\.\d+)?$/;
        var money = document.getElementById("Money").value;
        if(!isNum.test(money)){
            alert("请输入正确的金钱");
            return;
        }else{
            alert("输入正确");
        }
    }
  //-->
  </script>

------解决方案--------------------
/^[\d]*(.[\d]{1,2})?$/


------解决方案--------------------
2#正解