In this article I will explain how to validate Email ID on server
side (entered by user).
We can validate email address on client side by using validations controls
provided in Asp.NET. But they will not work if Javascript is disabled. In this
case server side validation will work and more reliable.
In this article we will validate Email id using RegEx.
In this article we will validate Email id using RegEx.
Demo:
Click here to Enlarge Image
Follow these steps to Validate Email Id Using RegEx on server
side:
Design your webpage:
<fieldset style="width:370px"><legend>Display Data in
Detail View Control</legend>
<br />
<table style="width:100%">
<tr><td>Enter Email:</td><td>
<asp:TextBox ID="txtEmail" runat="server" Width="200px"></asp:TextBox>
</td></tr>
<tr><td></td><td></td></tr>
<tr><td></td><td>
<asp:Button ID="btnEmail" runat="server" OnClick="btnEmail_Click" Text="Validate
Email" />
</td></tr>
<tr><td> </td><td> </td></tr>
<tr><td>Result:</td><td>
<asp:Label ID="lblresult" runat="server"></asp:Label>
</td></tr>
</table>
<br /></fieldset>
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ASP.NET code Using C# to validate EmailID:
First include the namespace as:
using
System.Text.RegularExpressions;
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Write Following function to validate Email:
public bool IsEmailValid(string Email)
{
string strRegex = "^([a-zA-Z0-9_\\-\\.]+)@((\\[[0-9]{1,3}" + "\\.[0-9]{1,3}\\.[0-9]{1,3}\\.)|(([a-zA-Z0-9\\-]+\\" + ".)+))([a-zA-Z]{2,4}|[0-9]{1,3})(\\]?)$";
Regex re = new Regex(strRegex);
if (re.IsMatch(Email))
{
return true;
}
else
{
return false;
}
}
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Now just call this function and pass the email address as a
parameter to check whether it is valid or not. e.g. on Button Click event as:
protected void btnEmail_Click(object sender, EventArgs e)
{
if (IsEmailValid(txtEmail.Text))
{
lblresult.Text="This Email
Id is Valid";
lblresult.ForeColor =
System.Drawing.Color.Green;
}
else
{
lblresult.Text = "This Email
Id is InValid";
lblresult.ForeColor =
System.Drawing.Color.Red;
}
}
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VB.NET Code to check whether email address valid or not
First import namespace
as:
imports System.Text.RegularExpressions
Public Function
IsEmailValid(Email As String) As Boolean
Dim strRegex As String = "^([a-zA-Z0-9_\-\.]+)@((\[[0-9]{1,3}" & "\.[0-9]{1,3}\.[0-9]{1,3}\.)|(([a-zA-Z0-9\-]+\" & ".)+))([a-zA-Z]{2,4}|[0-9]{1,3})(\]?)$"
Dim re As New Regex(strRegex)
If re.IsMatch(Email) Then
Return True
Else
Return False
End If
End Function
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Now just call this function and pass the email address as a
parameter to check whether it is valid or not. e.g. on Button Click event as:
Protected Sub
btnEmailCheck_Click(sender As Object, e As EventArgs) Handles
btnEmailCheck.Click
If IsEmailValid(txtEmail.Text) Then
Response.Write("Valid
Email Id")
Else
Response.Write("InValid
Email Id")
End If
End Sub
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