ASP.Net Form Validation Using JavaScript

Put the javascript code in the head section

JavaScript :

 <script language="javascript" type="text/javascript">

        function checkonlyalphabets(a, evt) {
            var charCode = evt.which ? evt.which : evt.keyCode;
            if ((charCode >= 65 && charCode <= 90) || (charCode >= 97 && charCode <= 122))
                return true;
            else {
                alert('Please! Enter Only Alphabets');
                return false;
            }
        }

        function checkonlynumbers(a, evt) {
            var charCode = (evt.which) ? evt.which : evt.keyCode
            if (charCode >= 48 && charCode <= 57)
                return true;
            else {
                alert('Please! Enter Only Numbers');
                return false;
            }
        }

        function validate() {
            var email = document.getElementById('txtEmail').value;
            var emailfilter = /^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/;
            var EmailMatch = email.match(emailfilter);
            if (!emailfilter.test(email.value)) {
                if (EmailMatch == null) {
                    alert('Please Insert Correct Email Address.');
                    return false;
                }               
            }

            var url = document.getElementById('txtUrl').value;          
            var urlfilter = /(http(s)?:\\)?([\w-]+\.)+[\w-]+[.com|.in|.org]+(\[\?%&=]*)?/;            
            var UrlMatch = url.match(urlfilter);            
            if (!urlfilter.test(url.value)) {
                if (UrlMatch == null) {
                    alert('Please Insert Correct URL.');
                    return false;
                }              
            }

        }

    </script>

Asp.Net :

  <table>
            <tr>
                <td>
                    Name (Alhabets Only)
                </td>
                <td>
                    <asp:TextBox ID="txtName" runat="server" onKeyPress="return checkonlyalphabets(this, event)" />
                </td>
            </tr>
            <tr>
                <td>
                    Email
                </td>
                <td>
                    <asp:TextBox ID="txtEmail" runat="server" />
                </td>
            </tr>
            <tr>
                <td>
                    Mobile (Numbers Only)
                </td>
                <td>
                    <asp:TextBox ID="txtMobile" runat="server" onKeyPress="return checkonlynumbers(this, event)" />
                </td>
            </tr>
            <tr>
                <td>
                    URL
                </td>
                <td>
                    <asp:TextBox ID="txtUrl" runat="server" />
                </td>
            </tr>
            <tr>
                <td>
                </td>
                <td>
                    <asp:Button ID="btnsubmit" runat="server" Text="Save" OnClientClick="return validate();" />
                </td>
            </tr>
        </table>