Saturday, May 23, 2015

Regular Expression Validate Email Id

<!DOCTYPE html>
<html>
<head id="Head1" runat="server">
    <title>ASP.Net - Regular Expression To Validate Email Address in C#.Net</title>
</head>
<body>
    <form id="frmValidate" name="frmValidate" runat="server">
    <div>
        <table border="1" cellpadding="5">
            <tr>
                <td>
                    Enter Email Id Here
                </td>
                <td>
                    <asp:TextBox ID="txtEmailId" runat="server"></asp:TextBox>
                </td>
            </tr>
            <tr>
                <td>
                </td>
                <td>
                    <asp:Button ID="btnValidateEmail" runat="server" Text="Check" OnClick="btnValidateEmail_Click" />
                </td>
            </tr>
            <tr>
                <td colspan="2">
                    <p style="color: Red;">
                        <asp:Label ID="lblValidEmail" runat="server"></asp:Label></p>
                </td>
            </tr>
        </table>
    </div>
    </form>
</body>
</html>

 C#.Net Code
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Text.RegularExpressions;

public partial class ValidateEmail : System.Web.UI.Page
{
    protected void btnValidateEmail_Click(object sender, EventArgs e)
    {
        //Check Email Id is valid
        if (IsValidEmailId(txtEmailId.Text))
        {
            lblValidEmail.Text = txtEmailId.Text + " is valid email";
        }
        else
        {
            lblValidEmail.Text = txtEmailId.Text + " is not valid email";
        }
    }
    //This function returns true if the emailid matches the pattern. Else it will return false
    private bool IsValidEmailId(string InputEmail)
    {
        //Regex To validate Email Address
        Regex regex = new Regex(@"^([\w\.\-]+)@([\w\-]+)((\.(\w){2,3})+)$");
        Match match = regex.Match(InputEmail);
        if (match.Success)
            return true;
        else
            return false;
    }

}