public bool IsValidEmail(string email)
    {
        try
        {
            var addr = new System.Net.Mail.MailAddress(email);
            return addr.Address == email;
        }
        catch
        {
            return false;
        }
    }

我发现这个正则表达式在检查@标记以外的东西和接受奇怪的边缘情况之间是一个很好的权衡:

^[^@\s]+@[^@\s]+(\.[^@\s]+)+$

它至少会让你在@标记周围放一些东西，并且至少放一个正常的域。

通过system . text . regulareexpressions检查电子邮件字符串的格式是否正确:

    public static bool IsValidEmailId(string InputEmail)
    {
        Regex regex = new Regex(@"^([\w\.\-]+)@([\w\-]+)((\.(\w){2,3})+)$");
        Match match = regex.Match(InputEmail);
        if (match.Success)
            return true;
        else
            return false;
    }

    protected void Email_TextChanged(object sender, EventArgs e)
    {
        String UserEmail = Email.Text;
        if (IsValidEmailId(UserEmail))
        {
            Label4.Text = "This email is correct formate";
        }
        else
        {
            Label4.Text = "This email isn't correct formate";
        }
    }

我经常用这个来验证电子邮件，它就像一个魅力。这验证了电子邮件必须在@之前至少有一个字符，并且在“”之前至少有一个字符。

public static bool ValidateEmail(string value, bool required, int minLength, int maxLength)
        {
           value = value.Trim();
           if (required == false && value == "") return true;
           if (required && value == "") return false;
           if (value.Length < minLength || value.Length > maxLength) return false;

           //Email must have at least one character before an @, and at least one character before the .
           int index = value.IndexOf('@');
           if (index < 1 || value.LastIndexOf('.') < index + 2) return false;
           return true;
        }

这是你问题的答案，供你核对。

using System;
using System.Globalization;
using System.Text.RegularExpressions;

public class RegexUtilities
{    
   public bool IsValidEmail(string strIn)
   {
       if (String.IsNullOrEmpty(strIn))
       {
          return false;

       }

       // Use IdnMapping class to convert Unicode domain names.

       try 
       {
          strIn = Regex.Replace(strIn, @"(@)(.+)$", this.DomainMapper, RegexOptions.None, TimeSpan.FromMilliseconds(200));

       }
       catch (RegexMatchTimeoutException) 
       {
           return false;

       }

       if (invalid)
       {
           return false;

       }

       // Return true if strIn is in valid e-mail format.    

       try 
       {
          return Regex.IsMatch(strIn, @"^(?("")("".+?(?<!\\)""@)|(([0-9a-z]((\.(?!\.))|       [-!#\$%&'\*\+/=\?\^`\{\}\|~\w])*)(?<=[0-9a-z])@))(?(\[)(\[(\d{1,3}\.){3}\d{1,3}\])|(([0-9a-z][-\w]*[0-9a-z]*\.)+[a-z0-9][\-a-z0-9]{0,22}[a-z0-9]))$", RegexOptions.IgnoreCase, TimeSpan.FromMilliseconds(250));

       }
       catch (RegexMatchTimeoutException) 
       {
          return false;

       }

   }


   private string DomainMapper(Match match)
   {
      // IdnMapping class with default property values.

      IdnMapping idn = new IdnMapping();

      string domainName = match.Groups[2].Value;

      try 
      {
         domainName = idn.GetAscii(domainName);

      }
      catch (ArgumentException) 
      {
         invalid = true;

      }

      return match.Groups[1].Value + domainName;

   }

}

我将Poyson 1的答案简化如下:

public static bool IsValidEmailAddress(string candidateEmailAddr)
{
    string regexExpresion = "\\w+([-+.']\\w+)*@\\w+([-.]\\w+)*\\.\\w+([-.]\\w+)*";
    return (Regex.IsMatch(candidateEmailAddr, regexExpresion)) && 
           (Regex.Replace(candidateEmailAddr, regexExpresion, string.Empty).Length == 0);
}