iOS开发复用代码小片段-判断邮箱是否合法的代码

转载自：http://blog.youkuaiyun.com/ipromiseu/article/details/6678261

//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]; }