本文共 2609 字，大约阅读时间需要 8 分钟。

方法一：

@interface NSString (ValidEmailAddition)  

 

- (BOOL)isValidEmail;

 

@end

 

 

@implementation NSString (ValidEmailAddition)  

 

- (BOOL)isValidEmail  

{  

    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 *regExPredicate = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", emailRegEx];  

    return [regExPredicate evaluateWithObject:self];  

}  

 

@end

方法二：

//判断邮箱是否合法的代码

-(BOOL)validateEmail:(NSString*)email

{

    if((0 != [email rangeOfString:@"@"].length) &&

         (0 != [email rangeOfString:@"."].length))

    {

          

           NSCharacterSet* tmpInvalidCharSet = [[NSCharacterSet alphanumericCharacterSet] invertedSet];

        NSMutableCharacterSet* tmpInvalidMutableCharSet = [[tmpInvalidCharSet mutableCopy] autorelease];

        [tmpInvalidMutableCharSet removeCharactersInString:@"_-"];

       

           //使用compare option 来设定比较规则，如

           //NSCaseInsensitiveSearch是不区分大小写

           //NSLiteralSearch 进行完全比较,区分大小写

           //NSNumericSearch 只比较定符串的个数，而不比较字符串的字面值

        NSRange range1 = [email rangeOfString:@"@"

                                              options:NSCaseInsensitiveSearch];

       

        //取得用户名部分

        NSString* userNameString = [email substringToIndex:range1.location];

        NSArray* userNameArray   = [userNameString componentsSeparatedByString:@"."];

          

        for(NSString* string in userNameArray)

           {

            NSRange rangeOfInavlidChars = [string rangeOfCharacterFromSet: tmpInvalidMutableCharSet];

            if(rangeOfInavlidChars.length != 0 || [string isEqualToString:@""])

                return NO;

        }

       

        NSString *domainString = [email substringFromIndex:range1.location+1];

        NSArray *domainArray   = [domainString componentsSeparatedByString:@"."];

       

        for(NSString *string in domainArray)

           {

            NSRange rangeOfInavlidChars=[string rangeOfCharacterFromSet:tmpInvalidMutableCharSet];

            if(rangeOfInavlidChars.length !=0 || [string isEqualToString:@""])

                return NO;

        }

     

        return YES;

    }

    else // no ''@'' or ''.'' present

        return NO;

}

 

 

 

 

BOOL NSStringIsValidEmail(NSString *checkString)  

{       NString *stricterFilterString = @"[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,4}";      NSString *laxString = @".+@.+\.[A-Za-z]{2}[A-Za-z]*";       NSString *emailRegex = stricterFilter ? stricterFilterString : laxString;       NSPredicate *emailTest = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", emailRegex];       return [emailTest evaluateWithObject:checkString];   }

转载地址：http://rjosi.baihongyu.com/