正则表达式
发布时间：2020-12-13 23:06:49 所属栏目：百科 来源：网络整理
导读：简述：Cocoa框架中的NSPredicate用于查询，原理和用法都类似于SQL中的where，作用相当于数据库的过滤
|
简述：Cocoa框架中的NSPredicate用于查询，原理和用法都类似于SQL中的where，作用相当于数据库的过滤取。 定义(最常用到的方法)： [cpp] view plaincopy NSPredicate *ca = [NSPredicate predicateWithFormat:(NSString *),...]; 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 [cpp] view plaincopy 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: [cpp] view plaincopy NSString *regex = @"[A-Za-z]+"; NSPredicate *predicate = [NSPredicate predicateWithFormat:@"SELF MATCHES %@",regex]; if ([predicate evaluateWithObject:aString]) { } (3)字符串替换： [cpp] view plaincopy 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$2"]; NSLog(@"Result:%@",result); (4)截取字符串如下： [cpp] view plaincopy //组装一个字符串，需要把里面的网址解析出来 NSString *urlString=@"<meta/><link/><title>1Q84 BOOK1</title></head><body>"; //NSRegularExpression类里面调用表达的方法需要传递一个NSError的参数。下面定义一个 NSError *error; //http+:[^s]* 这个表达式是检测一个网址的。(?<=title&;).*(?=</title)截取html文章中的<title></title>中内文字的正则表达式 NSRegularExpression *regex = [NSRegularExpression regularExpressionWithPattern:@"(?<=title>).*(?=</title)" options:0 error:&error]; if (regex != nil) { NSTextCheckingResult *firstMatch=[regex firstMatchInString:urlString options:0 range:NSMakeRange(0,[urlString length])]; if (firstMatch) { NSRange resultRange = [firstMatch rangeAtIndex:0]; //从urlString当中截取数据 NSString *result=[urlString substringWithRange:resultRange]; //输出结果 NSLog(@"->%@<-",result); } } (5)判断手机号码，电话号码函数 [cpp] view plaincopy // 正则判断手机号码地址格式 - (BOOL)isMobileNumber:(NSString *)mobileNum { /** * 手机号码 * 移动：134[0-8],135,136,137,138,139,150,151,157,158,159,182,187,188 * 联通：130,131,132,152,155,156,185,186 * 电信：133,1349,153,180,189 */ NSString * MOBILE = @"^1(3[0-9]|5[0-35-9]|8[025-9])d{8}$"; /** 10 * 中国移动：China Mobile 11 * 134[0-8],188 12 */ NSString * CM = @"^1(34[0-8]|(3[5-9]|5[017-9]|8[278])d)d{7}$"; /** 15 * 中国联通：China Unicom 16 * 130,186 17 */ NSString * CU = @"^1(3[0-2]|5[256]|8[56])d{8}$"; /** 20 * 中国电信：China Telecom 21 * 133,189 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: [cpp] view plaincopy //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 [cpp] view plaincopy //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]; /**< 模糊查找*/ NSPredicate *predicateString = [NSPredicate predicateWithFormat:@"%K contains[cd] %@",keyName,searchText]; /**< 精确查找*/ // NSPredicate *predicateString = [NSPredicate predicateWithFormat:@"%K == %@",searchText]; （编辑：李大同） 【声明】本站内容均来自网络，其相关言论仅代表作者个人观点，不代表本站立场。若无意侵犯到您的权利，请及时与联系站长删除相关内容! |