In email field should not allow special characters

mahesh

15y4kC#

Dear All,
For email validation,I,m using this regular expression \w+([-+.']\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*.I should not allow following special characters >> << < > ( ) { } [ ] ? & * ~ ` ! # $ % ^ = + | \ : ' " , ; .it's working fine when i enter special characters after word for example:david>>@cc.com but when i enter special characters in between character for example:dav>>[email protected]'s accepting that mail.Can any one tell me how can i do this?

Thanks in advance.

3 Replies

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Vulpes15y ago
Accepted answer
Doh, there's no wonder it's giving false for both email addresses in my example as I've got the email address and the regex expression the wrong way around in the Regex.IsMatch method call!

Sorry about that.

The reason why it's giving 'True' for dav>>[email protected] is because it's actually matching '[email protected]' which it can't do for david>>cc.com.

To solve this, you need to use anchors at the beginning and end of the regular expression:

using System;
using System.Text.RegularExpressions;

class Test
{
static void Main()
{
string r = @"^\w+([-+.']\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*$"; // added anchors
string email = @"[email protected]"; // OK
string email2 = @"dav>>[email protected]"; // Invalid
string email3 = @"david>>@cc.com"; // Invalid
bool b = Regex.IsMatch(email, r);
bool b2 = Regex.IsMatch(email2, r);
bool b3 = Regex.IsMatch(email3, r);
Console.WriteLine(b); // True
Console.WriteLine(b2); // False
Console.WriteLine(b3); // False
Console.ReadKey();
}
}
0
mahesh15y ago
Thank you so much.
0
Vulpes15y ago
I don't understand what the problem is as the following code returns False for both e-mail addresses:

using System;
using System.Text.RegularExpressions;

class Test
{
static void Main()
{
string r = @"\w+([-+.']\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*";
string email = @"dav>>[email protected]";
string email2 = @"david>>@cc.com";
bool b = Regex.IsMatch(r, email);
bool b2 = Regex.IsMatch(r, email2);
Console.WriteLine(b); // False
Console.WriteLine(b2); // False
Console.ReadKey();
}
}
0