This is a simple C# .NET Program to validate email address. The ValildateEmail() function checks for a valid email and returns true if the email address is a valid email otherwise it returns false if the email address is not proper syntax. The code is well commented and should explain what is happening .
This code uses regular expressions to validate the structure of the email address and checks for the presence of “@” and “.” characters. Additionally, it has a separate function ContainsIllegalCharacters to check for the presence of any illegal characters in the email address.
using System;
using System.Text.RegularExpressions;
class Program
{
static void Main()
{
string email = "user@example.com";
bool isValid = ValidateEmail(email);
if (isValid)
{
Console.WriteLine("Email is valid.");
}
else
{
Console.WriteLine("Email is invalid.");
}
}
static bool ValidateEmail(string email)
{
// Define the regular expression pattern for a valid email address
string pattern = @"^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$";
// Check if the email matches the pattern
if (Regex.IsMatch(email, pattern))
{
// Check for illegal characters
if (ContainsIllegalCharacters(email))
{
return false;
}
return true;
}
return false;
}
static bool ContainsIllegalCharacters(string input)
{
// Define a pattern for acceptable characters in the email
string acceptablePattern = @"^[a-zA-Z0-9._%+-@]+$";
// Check if the input contains any illegal characters
return !Regex.IsMatch(input, acceptablePattern);
}
}