iOS App开发中Objective-C使用正则表达式进行匹配的

iOS中有三种方式来实现正则表达式的匹配。现在将他们都记录在这里：

1.利用NSPredicate（谓词）匹配
例如匹配有效邮箱：

NSString ＊email ＝ @“nijino_saki@163.com”； 
NSString *regex = @"[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,4}"; 
NSPredicate *predicate = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", regex]; 
BOOL isValid = [predicate evaluateWithObject:email];

谓词匹配比较灵活，但是需要有谓词的相关知识。

2.利用rangeOfString：option：直接查找

NSString *searchText = @"// Do any additional setup after loading the view, typically from a nib."; 
 
NSRange range = [searchText rangeOfString:@"(?:[^,])*\\." options:NSRegularExpressionSearch]; 
 
if (range.location != NSNotFound) { 
  NSLog(@"%@", [searchText substringWithRange:range]); 
}

options中设定NSRegularExpressionSearch就是表示利用正则表达式匹配，会返回第一个匹配结果的位置。

3.使用正则表达式类

NSString *searchText = @"// Do any additional setup after loading the view, typically from a nib.";  
NSError *error = NULL;
NSRegularExpression *regex = [NSRegularExpression regularExpressionWithPattern:@"(?:[^,])*\\." options:NSRegularExpressionCaseInsensitive error:&error];
NSTextCheckingResult *result = [regex firstMatchInString:searchText options:0 range:NSMakeRange(0, [searchText length])];
if (result) {
  NSLog(@"%@\n", [searchText substringWithRange:result.range]);
}

使用系统的正则表达式类（NSRegularExpression）会返回匹配的多个结果。

实例：
1.验证邮箱

+ (BOOL)validateEmail:(NSString *)email
{
  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:email];
}

NSPredicate是一个Foundation类，是用来查询的，原理和用法都类似于SQL中的where。

2.验证手机号

简单的判断方法

+ (BOOL)validatePhone:(NSString *)phone
{
  NSString *phoneRegex = @"1[3|5|7|8|][0-9]{9}";
  NSPredicate *phoneTest = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", phoneRegex];
  return [phoneTest evaluateWithObject:phone];
}

这只是简单地判断手机号格式。其实手机的格式还是有一点复杂的。

详细的判断方法

//正则判断手机号码格式
+ (BOOL)validatePhone:(NSString *)phone
{
    /**
    * 手机号码
    * 移动：134[0-8],135,136,137,138,139,150,151,157,158,159,182,187,188
    * 联通：130,131,132,152,155,156,185,186
    * 电信：133,1349,153,180,189
    */
    NSString * MOBILE = @"^1(3[0-9]|5[0-35-9]|8[025-9])\\d{8}$";
    /**
         * 中国移动：China Mobile
         * 134[0-8],135,136,137,138,139,150,151,157,158,159,182,187,188
         */
    NSString * CM = @"^1(34[0-8]|(3[5-9]|5[017-9]|8[278])\\d)\\d{7}$";
    /**
         * 中国联通：China Unicom
         * 130,131,132,152,155,156,185,186
         */
    NSString * CU = @"^1(3[0-2]|5[256]|8[56])\\d{8}$";
    /**
         * 中国电信：China Telecom
         * 133,1349,153,180,189
         */
    NSString * CT = @"^1((33|53|8[09])[0-9]|349)\\d{7}$";
    /**
         * 大陆地区固话及小灵通
         * 区号：010,020,021,022,023,024,025,027,028,029
         * 号码：七位或八位
         */
   // NSString * PHS = @"^0(10|2[0-5789]|\\d{3})\\d{7,8}$";

   NSPredicate *regextestmobile = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", MOBILE];
   NSPredicate *regextestcm = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", CM];
   NSPredicate *regextestcu = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", CU];
   NSPredicate *regextestct = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", CT];

  if (([regextestmobile evaluateWithObject:phone] == YES)
  || ([regextestcm evaluateWithObject:phone] == YES)
  || ([regextestct evaluateWithObject:phone] == YES)
  || ([regextestcu evaluateWithObject:phone] == YES))
  {
    if([regextestcm evaluateWithObject:phone] == YES) {
     NSLog(@"China Mobile");
    } else if([regextestct evaluateWithObject:phone] == YES) {
     NSLog(@"China Telecom");
    } else if ([regextestcu evaluateWithObject:phone] == YES) {
     NSLog(@"China Unicom");
    } else {
     NSLog(@"Unknow");
    }

    return YES;
  }
  else 
  {
    return NO;
  }
}