Question

我尝试这个例子，但它有一些电子邮件类型没有检查。

- (BOOL) validateEmail: (NSString *) candidate {
    NSString *emailRegex =
@"(?:[a-z0-9!#$%\\&'*+/=?\\^_`{|}~-]+(?:\\.[a-z0-9!#$%\\&'*+/=?\\^_`{|}"
@"~-]+)*|\"(?:[\\x01-\\x08\\x0b\\x0c\\x0e-\\x1f\\x21\\x23-\\x5b\\x5d-\\"
@"x7f]|\\\\[\\x01-\\x09\\x0b\\x0c\\x0e-\\x7f])*\")@(?:(?:[a-z0-9](?:[a-"
@"z0-9-]*[a-z0-9])?\\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?|\\[(?:(?:25[0-5"
@"]|2[0-4][0-9]|[01]?[0-9][0-9]?)\\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-"
@"9][0-9]?|[a-z0-9-]*[a-z0-9]:(?:[\\x01-\\x08\\x0b\\x0c\\x0e-\\x1f\\x21"
@"-\\x5a\\x53-\\x7f]|\\\\[\\x01-\\x09\\x0b\\x0c\\x0e-\\x7f])+)\\])"; 
    NSPredicate *emailTest = [NSPredicate predicateWithFormat:@"SELF MATCHES[c] %@", emailRegex]; 

    return [emailTest evaluateWithObject:candidate];
}

此示例不检查类型为email @ domain.c-om，email @ domain.c＃omc，email @ 11.160.58.260，em#il@domain.com的电子邮件地址。检查电子邮件地址的正确方法是什么？避免使用该类型？

Answer 1

你从哪里得到了正则表达式？看起来你从http://www.regular-expressions.info/email.html得到它

你可以（但你不应该 - 继续阅读）用这个常规实现它表达

然后它说

你不应该使用这个正则表达式的原因是它只检查电子邮件地址的基本语法。 john@aol.com.nospam会的根据RFC 5322认为是有效的电子邮件地址。

然后该页面建议使用

[a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:\.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*@(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?

对于Objective-C，你必须转义反斜杠，你就完成了。

Answer 2

分类添加方法 isEmail

 -(BOOL)isEmail {
    BOOL stricterFilter = YES; 
    NSString *stricterFilterString = @"^[_A-Za-z0-9-+]+(\\.[_A-Za-z0-9-+]+)*@[A-Za-z0-9-]+(\\.  [A-Za-z0-9-]+)*(\\.[A-Za-z‌]{2,4})$";
    NSString *laxString = @".+@([A-Za-z0-9]+\\.)+[A-Za-z]{2}[A-Za-z]*";
    NSString *emailRegex = stricterFilter ? stricterFilterString : laxString;
    NSPredicate *emailTest = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", emailRegex];
    return [emailTest evaluateWithObject:self];
}

调用此方法

if([text isEmail]){
//validate email id
}else{
//not email id
}

Disscusion for Email Validation

Answer 3

试试这个：

+ (BOOL)validateEmail:(NSString *)candidate
{
    NSString *emailRegex = @"[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,4}";
    NSPredicate *emailTest = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", emailRegex];
    return [emailTest evaluateWithObject:candidate];
}

Answer 4

尝试使用此代码验证给定字符串是否为电子邮件。

- (BOOL)validEmail:(NSString *) emailString
{
    if([emailString length]==0)
    {
        return NO;
    }
    NSString *regExPattern = @"[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,4}";
    NSRegularExpression *regEx = [[NSRegularExpression alloc] initWithPattern:regExPattern options:NSRegularExpressionCaseInsensitive error:nil];
    NSUInteger regExMatches = [regEx numberOfMatchesInString:emailString options:0 range:NSMakeRange(0, [emailString length])];

    if (regExMatches == 0)
    {
        return NO;
    }
    else
    {
        return YES;
    }
}

Answer 5

+（BOOL）validEmailid：（NSString *）emailId {

 @try

  {

   BOOL stricterFilter = NO;

    NSString *stricterFilterString = @"[A-Z0-9a-z\\._%+-]+@([A-Za-z0-9-]+\\.)+[A-Za-z]{2,4}";

    NSString *laxString = @".+@([A-Za-z0-9-]+\\.)+[A-Za-z]{2}[A-Za-z]*";

    NSString *emailRegex = stricterFilter ? stricterFilterString : laxString;

    NSPredicate *emailTest = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", emailRegex];

    if ([emailTest evaluateWithObject:emailId]){
        return YES;
    }
    else{
        [self showalertwithmessage:@"Invalid emailid"];

        return NO;
    }

}
@catch (NSException *exception)
{
    NSLog(@"Error occurred in in Utils::stringIsValidEmail : %@",[exception description]);
}

}

如何验证电子邮件地址

5 个答案: