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NSPredicate

Format:
(1)比较运算符>,<,==,>=,<=,!=
可用于数值及字符串
例:@"number > 100"


(2)范围运算符:IN、BETWEEN
例:@"number BETWEEN {1,5}"
      @"address IN {‘shanghai‘,‘beijing‘}"


(3)字符串本身:SELF 
例:@“SELF == ‘APPLE’"


(4)字符串相关:BEGINSWITH、ENDSWITH、CONTAINS
例:@"name CONTAIN[cd] ‘ang‘"   //包含某个字符串
       @"name BEGINSWITH[c] ‘sh‘"     //以某个字符串开头
       @"name ENDSWITH[d] ‘ang‘"      //以某个字符串结束
        注:[c]不区分大小写[d]不区分发音符号即没有重音符号[cd]既不区分大小写,也不区分发音符号。


(5)通配符:LIKE
例:@"name LIKE[cd] ‘*er*‘"    //*代表通配符,Like也接受[cd].
       @"name LIKE[cd] ‘???er*‘"

 


(6)正则表达式:MATCHES
例:NSString *regex = @"^A.+e$";   //以A开头,e结尾
      @"name MATCHES %@",regex

 

实际应用:
(1)对NSArray进行过滤

NSArray *array = [[NSArray alloc]initWithObjects:@"beijing",@"shanghai",@"guangzou",@"wuhan", nil];    NSString *string = @"ang";    NSPredicate *pred = [NSPredicate predicateWithFormat:@"SELF CONTAINS %@",string];    NSLog(@"%@",[array filteredArrayUsingPredicate:pred]); 

(2)判断字符串首字母是否为字母:

NSString *regex = @"[A-Za-z]+";    NSPredicate *predicate = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", regex];        if ([predicate evaluateWithObject:aString]) {    }  

(3)字符串替换:

NSError* error = NULL;    NSRegularExpression* regex = [NSRegularExpression regularExpressionWithPattern:@"(encoding=\")[^\"]+(\")"                                                                                options:0                                                                                error:&error];    NSString* sample = @"<xml encoding=\"abc\"></xml><xml encoding=\"def\"></xml><xml encoding=\"ttt\"></xml>";    NSLog(@"Start:%@",sample);    NSString* result = [regex stringByReplacingMatchesInString:sample                                                          options:0                                                           range:NSMakeRange(0, sample.length)                                                          withTemplate:@"$1utf-8$2"];    NSLog(@"Result:%@", result);

(4)截取字符串如下:

//组装一个字符串,需要把里面的网址解析出来    NSString *urlString=@"<meta/><link/><title>1Q84 BOOK1</title></head><body>";        //NSRegularExpression类里面调用表达的方法需要传递一个NSError的参数。下面定义一个      NSError *error;        //http+:[^\\s]* 这个表达式是检测一个网址的。(?<=title\>).*(?=</title)截取html文章中的<title></title>中内文字的正则表达式    NSRegularExpression *regex = [NSRegularExpression regularExpressionWithPattern:@"(?<=title\\>).*(?=</title)" options:0 error:&error];        if (regex != nil) {        NSTextCheckingResult *firstMatch=[regex firstMatchInString:urlString options:0 range:NSMakeRange(0, [urlString length])];                if (firstMatch) {            NSRange resultRange = [firstMatch rangeAtIndex:0];                        //从urlString当中截取数据            NSString *result=[urlString substringWithRange:resultRange];            //输出结果            NSLog(@"->%@<-",result);        }            }  

(5)判断手机号码,电话号码函数  

// 正则判断手机号码地址格式  - (BOOL)isMobileNumber:(NSString *)mobileNum  {         /**         * 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}$";         /**         10         * 中国移动:China Mobile         11         * 134[0-8],135,136,137,138,139,150,151,157,158,159,182,187,188         12         */         NSString * CM = @"^1(34[0-8]|(3[5-9]|5[017-9]|8[278])\\d)\\d{7}$";         /**         15         * 中国联通:China Unicom         16         * 130,131,132,152,155,156,185,186         17         */         NSString * CU = @"^1(3[0-2]|5[256]|8[56])\\d{8}$";         /**         20         * 中国电信:China Telecom         21         * 133,1349,153,180,189         22         */         NSString * CT = @"^1((33|53|8[09])[0-9]|349)\\d{7}$";         /**         25         * 大陆地区固话及小灵通         26         * 区号:010,020,021,022,023,024,025,027,028,029         27         * 号码:七位或八位         28         */        // 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:mobileNum] == YES)      || ([regextestcm evaluateWithObject:mobileNum] == YES)      || ([regextestct evaluateWithObject:mobileNum] == YES)      || ([regextestcu evaluateWithObject:mobileNum] == YES))      {          if([regextestcm evaluateWithObject:mobileNum] == YES) {            NSLog(@"China Mobile");          } else if([regextestct evaluateWithObject:mobileNum] == YES) {            NSLog(@"China Telecom");          } else if ([regextestcu evaluateWithObject:mobileNum] == YES) {            NSLog(@"China Unicom");          } else {            NSLog(@"Unknow");          }                    return YES;      }      else       {          return NO;      }  }  

(6)邮箱验证、电话号码验证:

//是否是有效的正则表达式    +(BOOL)isValidateRegularExpression:(NSString *)strDestination byExpression:(NSString *)strExpression    {       NSPredicate *predicate = [NSPredicatepredicateWithFormat:@"SELF MATCHES %@", strExpression];         return [predicate evaluateWithObject:strDestination];    }    //验证email  +(BOOL)isValidateEmail:(NSString *)email {       NSString *strRegex = @"[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{1,5}";       BOOL rt = [CommonTools isValidateRegularExpression:email byExpression:strRegex];       return rt;    }    //验证电话号码  +(BOOL)isValidateTelNumber:(NSString *)number {       NSString *strRegex = @"[0-9]{1,20}";       BOOL rt = [CommonTools isValidateRegularExpression:number byExpression:strRegex];       return rt;    }  

(7)NSDate进行筛选

//日期在十天之内:  NSDate *endDate = [[NSDate date] retain];  NSTimeInterval timeInterval= [endDate timeIntervalSinceReferenceDate];  timeInterval -=3600*24*10;  NSDate *beginDate = [[NSDate dateWithTimeIntervalSinceReferenceDate:timeInterval] retain];  //对coredata进行筛选(假设有fetchRequest)  NSPredicate *predicate_date =  [NSPredicate predicateWithFormat:@"date >= %@ AND date <= %@", beginDate,endDate];        [fetchRequest setPredicate:predicate_date];  //释放retained的对象  [endDate release];  [beginDate release]; 

 

NSPredicate