A regular expression known as regex in short is a special text string which describes a search pattern.
Here is a c# function which accept a string as input parameter and return true if string is valid Email address and return false if string is not valid .
For this function to work properly you have to add these namespaces.
using System.Text;
using System.Text.RegularExpressions;
protected bool checkEmail(string Emailtext)
{
Regex MyEmailRegex = new Regex(@"^([a-zA-Z0-9_\-\.]+)@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.)|(([a-zA-Z0-9\-]+\.)+))([a-zA-Z]{2,4}|[0-9]{1,3})(\]?)$");
if (string.IsNullOrEmpty(Emailtext))
{
return false;
}
else
{
return MyEmailRegex.IsMatch(Emailtext);
}
}
