iOS中正则表达式的应用-NSPredicate
iOS中正则表达式的使用--NSPredicate
首先举一个例子:
匹配9-15个由字母/数字组成的字符串的正则表达式:
NSString * regex = @"^[A-Za-z0-9]{9,15}$";
NSPredicate *pred = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", regex];
BOOL isMatch = [pred evaluateWithObject:txtfldPhoneNumber.text];
参考文章地址:http://hi.baidu.com/%D3%D0%CF%E3%D1%CC%C3%BB%BB%F0%B2%F1/blog/item/da1b3aa3c5d64289d0435821.html
首先举一个例子:
匹配9-15个由字母/数字组成的字符串的正则表达式:
NSString * regex = @"^[A-Za-z0-9]{9,15}$";
NSPredicate *pred = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", regex];
BOOL isMatch = [pred evaluateWithObject:txtfldPhoneNumber.text];
Cocoa用NSPredicate描述查询的方式,原理类似于在数据库中进行查询
用BETWEEN,IN,BEGINWITH,ENDWITH,CONTAINS,LIKE这些谓词来构造NSPredicate,必要的时候使用SELF直接对自己进行匹配
//基本的查询 NSPredicate *predicate; predicate = [NSPredicate predicateWithFormat: @"name == 'Herbie'"]; BOOL match = [predicate evaluateWithObject: car]; NSLog (@"%s", (match) ? "YES" : "NO"); //在整个cars里面循环比较 predicate = [NSPredicate predicateWithFormat: @"engine.horsepower > 150"]; NSArray *cars = [garage cars]; for (Car *car in [garage cars]) { if ([predicate evaluateWithObject: car]) { NSLog (@"%@", car.name); } } //输出完整的信息 predicate = [NSPredicate predicateWithFormat: @"engine.horsepower > 150"]; NSArray *results; results = [cars filteredArrayUsingPredicate: predicate]; NSLog (@"%@", results); //含有变量的谓词 NSPredicate *predicateTemplate = [NSPredicate predicateWithFormat:@"name == $NAME"]; NSDictionary *varDict; varDict = [NSDictionary dictionaryWithObjectsAndKeys: @"Herbie", @"NAME", nil]; predicate = [predicateTemplate predicateWithSubstitutionVariables: varDict]; NSLog(@"SNORGLE: %@", predicate); match = [predicate evaluateWithObject: car]; NSLog (@"%s", (match) ? "YES" : "NO"); //注意不能使用$VARIABLE作为路径名,因为它值代表值 //谓词字符窜还支持c语言中一些常用的运算符 predicate = [NSPredicate predicateWithFormat: @"(engine.horsepower > 50) AND (engine.horsepower < 200)"]; results = [cars filteredArrayUsingPredicate: predicate]; NSLog (@"oop %@", results); predicate = [NSPredicate predicateWithFormat: @"name < 'Newton'"]; results = [cars filteredArrayUsingPredicate: predicate]; NSLog (@"%@", [results valueForKey: @"name"]); //强大的数组运算符 predicate = [NSPredicate predicateWithFormat: @"engine.horsepower BETWEEN { 50, 200 }"]; results = [cars filteredArrayUsingPredicate: predicate]; NSLog (@"%@", results); NSArray *betweens = [NSArray arrayWithObjects: [NSNumber numberWithInt: 50], [NSNumber numberWithInt: 200], nil]; predicate = [NSPredicate predicateWithFormat: @"engine.horsepower BETWEEN %@", betweens]; results = [cars filteredArrayUsingPredicate: predicate]; NSLog (@"%@", results); predicateTemplate = [NSPredicate predicateWithFormat: @"engine.horsepower BETWEEN $POWERS"]; varDict = [NSDictionary dictionaryWithObjectsAndKeys: betweens, @"POWERS", nil]; predicate = [predicateTemplate predicateWithSubstitutionVariables: varDict]; results = [cars filteredArrayUsingPredicate: predicate]; NSLog (@"%@", results); //IN运算符 predicate = [NSPredicate predicateWithFormat: @"name IN { 'Herbie', 'Snugs', 'Badger', 'Flap' }"]; results = [cars filteredArrayUsingPredicate: predicate]; NSLog (@"%@", [results valueForKey: @"name"]); predicate = [NSPredicate predicateWithFormat: @"SELF.name IN { 'Herbie', 'Snugs', 'Badger', 'Flap' }"]; results = [cars filteredArrayUsingPredicate: predicate]; NSLog (@"%@", [results valueForKey: @"name"]); names = [cars valueForKey: @"name"]; predicate = [NSPredicate predicateWithFormat: @"SELF IN { 'Herbie', 'Snugs', 'Badger', 'Flap' }"]; results = [names filteredArrayUsingPredicate: predicate];//这里限制了SELF的范围 NSLog (@"%@", results); //BEGINSWITH,ENDSWITH,CONTAINS //附加符号,[c],[d],[cd],c表示不区分大小写,d表示不区分发音字符,cd表示什么都不区分 predicate = [NSPredicate predicateWithFormat: @"name BEGINSWITH 'Bad'"]; results = [cars filteredArrayUsingPredicate: predicate]; NSLog (@"%@", results); predicate = [NSPredicate predicateWithFormat: @"name BEGINSWITH 'HERB'"]; results = [cars filteredArrayUsingPredicate: predicate]; NSLog (@"%@", results); predicate = [NSPredicate predicateWithFormat: @"name BEGINSWITH[cd] 'HERB'"]; results = [cars filteredArrayUsingPredicate: predicate]; NSLog (@"%@", results); //LIKE运算符(通配符) predicate = [NSPredicate predicateWithFormat: @"name LIKE[cd] '*er*'"]; results = [cars filteredArrayUsingPredicate: predicate]; NSLog (@"%@", results); predicate = [NSPredicate predicateWithFormat: @"name LIKE[cd] '???er*'"]; results = [cars filteredArrayUsingPredicate: predicate]; NSLog (@"%@", results);
参考文章地址:http://hi.baidu.com/%D3%D0%CF%E3%D1%CC%C3%BB%BB%F0%B2%F1/blog/item/da1b3aa3c5d64289d0435821.html