Allow Only Numbers In ASP TextBox and Html TextBox Using JAvaScript

22:25
Here I am Explaining asp TextBox and Html TextBox Allow only Digits Using JavaScript Code.
1. Design the aspx page like below.

<body>
    <form id="form1" runat="server">
    <div>
        <table>
            <tr>
                <td>
                    Asp TextBox:
                </td>
                <td>
                    <asp:TextBox ID="txtasp" runat="server"></asp:TextBox>
                </td>
            </tr>
            <tr>
                <td>
                    HTML TextBox:
                </td>
                <td>
                    <input type="text" runat="server" id="txthtml" />
                </td>
            </tr>
        </table>
    </div>
    </form>
</body>
2.Add javascript code to aspx source page head section.
<head runat="server">
    <title></title>
    <script type="text/javascript" language="javascript">

    // JAVASCRIPT CODE FOR HTML TEXT BOX..
        function numeric(e) {
            var unicode = e.charCode ? e.charCode : e.keyCode;
            if (unicode == 8 || unicode == 9 || (unicode >= 48 && unicode <= 57)) {
                return true;
            }
            else {
                alert('Please Enter Digits Only')
                return false;
            }
        }

        // JAVASCRIPT CODE FOR ASP TEXT BOX..
        function isNumberKey(event) {
            var charCode = (event.which) ? event.which : event.keyCode
            if (charCode > 31 && (charCode < 48 || charCode > 57)) {
                alert("Pls Enter Digits Only");
                return false;
            }
            return true;
        }
    </script>
</head>
3.Apply the java script to textboxes like below..
<asp:TextBox ID="txtasp" runat="server" OnKeyPress="return isNumberKey(event);"></asp:TextBox>
<input type="text" runat="server" id="txthtml" onkeypress="return numeric(event); " />
4.then run the application or press F5 and observe the screen..