我用这个
@"^([\w\.\-]+)@([\w\-]+)((\.(\w){2,3})+)$"
Regexp来验证电子邮件
([\w\.\-]+) -用于第一级域名(许多字母和数字，也有点和连字符) ([\w\-]+) -用于二级域 ((\.(\w){2,3})+) -这是用于其他级别域(从3到无穷)，其中包括一个点和2或3个字面量
这个正则表达式有什么问题?
编辑:它与“something@someth.ing”电子邮件不匹配
当前回答
我在MSDN上找到了一个很好的文档。
如何:验证字符串是否在有效的电子邮件格式 http://msdn.microsoft.com/en-us/library/01escwtf.aspx (请注意，这段代码还支持在Internet域名中使用非ascii字符。)
有两个实现，用于。net 2.0/3.0和用于。net 3.5及更高版本。 2.0/3.0版本为:
bool IsValidEmail(string strIn)
{
// Return true if strIn is in valid e-mail format.
return Regex.IsMatch(strIn, @"^([\w-\.]+)@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.)|(([\w-]+\.)+))([a-zA-Z]{2,4}|[0-9]{1,3})(\]?)$");
}
我对这个方法的测试给出:
Invalid: @majjf.com
Invalid: A@b@c@example.com
Invalid: Abc.example.com
Valid: j..s@proseware.com
Valid: j.@server1.proseware.com
Invalid: js*@proseware.com
Invalid: js@proseware..com
Valid: ma...ma@jjf.co
Valid: ma.@jjf.com
Invalid: ma@@jjf.com
Invalid: ma@jjf.
Invalid: ma@jjf..com
Invalid: ma@jjf.c
Invalid: ma_@jjf
Invalid: ma_@jjf.
Valid: ma_@jjf.com
Invalid: -------
Valid: 12@hostname.com
Valid: d.j@server1.proseware.com
Valid: david.jones@proseware.com
Valid: j.s@server1.proseware.com
Invalid: j@proseware.com9
Valid: j_9@[129.126.118.1]
Valid: jones@ms1.proseware.com
Invalid: js#internal@proseware.com
Invalid: js@proseware.com9
Invalid: js@proseware.com9
Valid: m.a@hostname.co
Valid: m_a1a@hostname.com
Valid: ma.h.saraf.onemore@hostname.com.edu
Valid: ma@hostname.com
Invalid: ma@hostname.comcom
Invalid: MA@hostname.coMCom
Valid: ma12@hostname.com
Valid: ma-a.aa@hostname.com.edu
Valid: ma-a@hostname.com
Valid: ma-a@hostname.com.edu
Valid: ma-a@1hostname.com
Valid: ma.a@1hostname.com
Valid: ma@1hostname.com
其他回答
我认为你的插入符号和美元符号是问题的一部分 你也应该修改一下正则表达式，我用的是下一个 @"[ :]+([\ w -] +) @ ((\ w -.])+((.(\ w){2,3}) +)”
string patternEmail = @"(?<email>\w+@\w+\.[a-z]{0,3})";
Regex regexEmail = new Regex(patternEmail);
public bool VailidateEntriesForAccount()
{
if (!(txtMailId.Text.Trim() == string.Empty))
{
if (!IsEmail(txtMailId.Text))
{
Logger.Debug("Entered invalid Email ID's");
MessageBox.Show("Please enter valid Email Id's" );
txtMailId.Focus();
return false;
}
}
}
private bool IsEmail(string strEmail)
{
Regex validateEmail = new Regex("^[\\W]*([\\w+\\-.%]+@[\\w\\-.]+\\.[A-Za-z] {2,4}[\\W]*,{1}[\\W]*)*([\\w+\\-.%]+@[\\w\\-.]+\\.[A-Za-z]{2,4})[\\W]*$");
return validateEmail.IsMatch(strEmail);
}
以下是我从这里收集信息和微软文档后的解决方案:
/// <summary>
/// * TLD support from 2 to 5 chars (modify the values as you want)
/// * Supports: abc@gmail.com.us
/// * Non-sensitive case
/// * Stops operation if takes longer than 250ms and throw a detailed exception
/// </summary>
/// <param name="email"></param>
/// <returns>valid: true | invalid: false </returns>
/// <exception cref="ArgumentException"></exception>
private bool validateEmailPattern(string email) {
try {
return Regex.IsMatch(email,
@"^([\w\.\-]+)@([\w\-]+)((\.(\w){2,5})+)$",
RegexOptions.None, TimeSpan.FromMilliseconds(250));
} catch (RegexMatchTimeoutException) {
// throw an exception explaining the task was failed
_ = email ?? throw new ArgumentException("email, Timeout/failed regexr processing.", nameof(email));
}
}
作为Alex的流行答案的更新:在。net 5中，MailAddress现在有一个TryCreate。所以你可以这样做:
public static bool IsValidEmail(string email)
{
if (!MailAddress.TryCreate(email, out var mailAddress))
return false;
// And if you want to be more strict:
var hostParts = mailAddress.Host.Split('.');
if (hostParts.Length == 1)
return false; // No dot.
if (hostParts.Any(p => p == string.Empty))
return false; // Double dot.
if (hostParts[^1].Length < 2)
return false; // TLD only one letter.
if (mailAddress.User.Contains(' '))
return false;
if (mailAddress.User.Split('.').Any(p => p == string.Empty))
return false; // Double dot or dot at end of user part.
return true;
}
