How to validate an email address in C#?

There are several ways to validate an email address in C#.

System.Net.Mail −The System.Net.Mail namespace contains classes used to send electronic mail to a Simple Mail Transfer Protocol (SMTP) server for delivery.

System.Text.RegularExpressions − Represents an immutable regular expression.

Use the below expression

@"^([a-zA-Z0-9_\-\.]+)@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.)|(([a-zA-Z0-9\-]+\.)+))([azA-Z]{2,4}|[0-9]{1,3})(\]?)$"

We can use the MailAddress class of the System.Net.Mail namespace to validate an email address

Example

 Live Demo

using System; using System.Net.Mail; namespace DemoApplication{    class Program{       public static void Main(){          try{             string email = "hello@xyzcom";             Console.WriteLine($"The email is {email}");             var mail = new MailAddress(email);             bool isValidEmail = mail.Host.Contains(".");             if(!isValidEmail){                Console.WriteLine($"The email is invalid");             } else {                Console.WriteLine($"The email is valid");             }             Console.ReadLine();          }          catch(Exception){             Console.WriteLine($"The email is invalid");             Console.ReadLine();          }       }    } }

Output

The output of the above code is

The email is hello@xyzcom The email is invalid

Example using Regex −

We can also use regular expression to validate an email address.

Example

using System; using System.Text.RegularExpressions; namespace DemoApplication{    public class Program{       public static void Main(){          string email = "hello@xyz.com";          Regex regex = new Regex(@"^([a-zA-Z0-9_\-\.]+)@((\[[0-9]{1,3}\.[0-          9]{1,3}\.[0-9]{1,3}\.)|(([a-zA-Z0-9\-]+\.)+))([a-zA-Z]{2,4}|[0-9]{1,3})(\]?)$",          RegexOptions.CultureInvariant | RegexOptions.Singleline);          Console.WriteLine($"The email is {email}");          bool isValidEmail = regex.IsMatch(email);          if (!isValidEmail){             Console.WriteLine($"The email is invalid");          } else {             Console.WriteLine($"The email is valid");          }          Console.ReadLine();       }    } }

Output

The output of the above code is

The email is hello@xyz.com The email is valid