我用这个
@"^([\w\.\-]+)@([\w\-]+)((\.(\w){2,3})+)$"
Regexp来验证电子邮件
([\w\.\-]+) -用于第一级域名(许多字母和数字,也有点和连字符) ([\w\-]+) -用于二级域 ((\.(\w){2,3})+) -这是用于其他级别域(从3到无穷),其中包括一个点和2或3个字面量
这个正则表达式有什么问题?
编辑:它与“something@someth.ing”电子邮件不匹配
我用这个
@"^([\w\.\-]+)@([\w\-]+)((\.(\w){2,3})+)$"
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
没有完美的正则表达式,但我认为,基于对RFC5322的研究,这个正则表达式相当强大。用c#字符串插值,我认为也很容易理解。
const string atext = @"a-zA-Z\d!#\$%&'\*\+-/=\?\^_`\{\|\}~";
var localPart = $"[{atext}]+(\\.[{atext}]+)*";
var domain = $"[{atext}]+(\\.[{atext}]+)*";
Assert.That(() => EmailRegex = new Regex($"^{localPart}@{domain}$", Compiled),
Throws.Nothing);
用NUnit 2.x检查。
其他回答
这并不满足rfc 5321和5322的所有要求,但它适用于以下定义。
@"^([0-9a-zA-Z]([\+\-_\.][0-9a-zA-Z]+)*)+"@(([0-9a-zA-Z][-\w]*[0-9a-zA-Z]*\.)+[a-zA-Z0-9]{2,17})$";
下面是代码
const String pattern =
@"^([0-9a-zA-Z]" + //Start with a digit or alphabetical
@"([\+\-_\.][0-9a-zA-Z]+)*" + // No continuous or ending +-_. chars in email
@")+" +
@"@(([0-9a-zA-Z][-\w]*[0-9a-zA-Z]*\.)+[a-zA-Z0-9]{2,17})$";
var validEmails = new[] {
"ma@hostname.com",
"ma@hostname.comcom",
"MA@hostname.coMCom",
"m.a@hostname.co",
"m_a1a@hostname.com",
"ma-a@hostname.com",
"ma-a@hostname.com.edu",
"ma-a.aa@hostname.com.edu",
"ma.h.saraf.onemore@hostname.com.edu",
"ma12@hostname.com",
"12@hostname.com",
};
var invalidEmails = new[] {
"Abc.example.com", // No `@`
"A@b@c@example.com", // multiple `@`
"ma...ma@jjf.co", // continuous multiple dots in name
"ma@jjf.c", // only 1 char in extension
"ma@jjf..com", // continuous multiple dots in domain
"ma@@jjf.com", // continuous multiple `@`
"@majjf.com", // nothing before `@`
"ma.@jjf.com", // nothing after `.`
"ma_@jjf.com", // nothing after `_`
"ma_@jjf", // no domain extension
"ma_@jjf.", // nothing after `_` and .
"ma@jjf.", // nothing after `.`
};
foreach (var str in validEmails)
{
Console.WriteLine("{0} - {1} ", str, Regex.IsMatch(str, pattern));
}
foreach (var str in invalidEmails)
{
Console.WriteLine("{0} - {1} ", str, Regex.IsMatch(str, pattern));
}
Visual studio已经有很多年了。
\w+([-+.']\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*
希望这能有所帮助!
以下代码是基于微软在github上的数据注释实现的,我认为这是对电子邮件最完整的验证:
public static Regex EmailValidation()
{
const string pattern = @"^((([a-z]|\d|[!#\$%&'\*\+\-\/=\?\^_`{\|}~]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])+(\.([a-z]|\d|[!#\$%&'\*\+\-\/=\?\^_`{\|}~]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])+)*)|((\x22)((((\x20|\x09)*(\x0d\x0a))?(\x20|\x09)+)?(([\x01-\x08\x0b\x0c\x0e-\x1f\x7f]|\x21|[\x23-\x5b]|[\x5d-\x7e]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])|(\\([\x01-\x09\x0b\x0c\x0d-\x7f]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF]))))*(((\x20|\x09)*(\x0d\x0a))?(\x20|\x09)+)?(\x22)))@((([a-z]|\d|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])|(([a-z]|\d|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])([a-z]|\d|-|\.|_|~|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])*([a-z]|\d|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])))\.)+(([a-z]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])|(([a-z]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])([a-z]|\d|-|\.|_|~|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])*([a-z]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])))\.?$";
const RegexOptions options = RegexOptions.Compiled | RegexOptions.IgnoreCase | RegexOptions.ExplicitCapture;
// Set explicit regex match timeout, sufficient enough for email parsing
// Unless the global REGEX_DEFAULT_MATCH_TIMEOUT is already set
TimeSpan matchTimeout = TimeSpan.FromSeconds(2);
try
{
if (AppDomain.CurrentDomain.GetData("REGEX_DEFAULT_MATCH_TIMEOUT") == null)
{
return new Regex(pattern, options, matchTimeout);
}
}
catch
{
// Fallback on error
}
// Legacy fallback (without explicit match timeout)
return new Regex(pattern, options);
}
在c#中使用regex方法进行字符串搜索
如何通过正则表达式验证电子邮件?
string EmailPattern = @"\w+([-+.']\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*";
if (Regex.IsMatch(Email, EmailPattern, RegexOptions.IgnoreCase))
{
Console.WriteLine("Email: {0} is valid.", Email);
}
else
{
Console.WriteLine("Email: {0} is not valid.", Email);
}
使用Reference String.Regex()方法
这可以防止其他人在评论中提到的无效邮件:
Abc.@example.com
Abc..123@example.com
name@hotmail
toms.email.@gmail.com
test@-online.com
它还可以防止带有双点的电子邮件:
hello..world@example..com
试着用尽可能多的无效电子邮件地址进行测试。
using System.Text.RegularExpressions;
public static bool IsValidEmail(string email)
{
return Regex.IsMatch(email, @"\A[a-z0-9]+([-._][a-z0-9]+)*@([a-z0-9]+(-[a-z0-9]+)*\.)+[a-z]{2,4}\z")
&& Regex.IsMatch(email, @"^(?=.{1,64}@.{4,64}$)(?=.{6,100}$).*");
}
请参阅在c#中使用正则表达式验证电子邮件地址。