asp.net 的给文本框指定字符、（event.keyCode） javascript

指定text1文本框只能输入1234567;

 <form id="form1" runat="server">

    <div>

     <input  id="text1" type="text" onkeyup="checkinput('1234567',event)" />

    </div>
    </form>

<script type="text/javascript" >

      function checkinput(codes,e) {              //在火狐下的 、、

       

         var key1 = window.event ? e.keyCode : e.which;          //  火狐获取键盘 按下的 asc 码  

    

            for (var i = 0; i < codes.length; i++) {

                alert(codes.charCodeAt(i))

                  

            if (key1 == codes.charCodeAt(i)) {                            // codes.charCodeAt(i) 是取下表 为 i 的asc码

                return true;

                

            }

        }

        document.getElementById("text1").value = document.getElementById("text1").value.substr(0, document.getElementById("text1").value.length - 1);

       

        return false;

    }

 

    

</script>

 <script type="text/javascript">

                        function checkinput(codes) {

                            for (var i = 0; i < codes.length; i++) {

                            

                                if (event.keyCode == codes.charCodeAt(i)) {

                                    return true;

                                }

                            }

                           

                            document.getElementById("Text1").value = document.getElementById("Text1").value.substr(0, document.getElementById("Text1").value.length - 1);

                           

                            return false;

                        }

    </script>