iOS 查询数组中的对象谓词NSPredicate

转载于 2016-08-05 14:21:32 发布 · 2.4k 阅读

本文介绍了如何使用NSPredicate进行字符串和对象属性的精确及模糊匹配，包括基于NSString对象的简单过滤和基于自定义对象属性的复杂查询。

1.NSString 对象
NSArray *array =@["123", @"234" , @"345"];
NSPredicate *predicate = [NSPredicate predicateWithFormat:@"SELF contains [cd] %@", "2"];
NSArray *filterdArray = [array filterdArrayUsingPredicate:predicate];
NSLog(@"%@", filterdArray );
//output : @"123", "234"
2.含有属性的对象
@interface Person: NSObject
{
NSString *_name;
NSString *_telephone;
NSInteger _id;
}
@property (nonatomic, copy) NSString *name;
@property (nonatomic, copy) NSString *telephone;
@property (nonatomic, assign) NSInteger id;
@end
//
1）.等于查询
NSPredicate *predicate = [NSPredicate predicateWithFormat:@"name == %@", "Ansel"];
NSArray *filteredArray = [array filteredArrayUsingPredicate:predicate];
2）.模糊查询
NSPredicate *predicate = [NSPredicate predicateWithFormat:@"name CONTAINS %@", @"A"]; //predicate只能是对象
NSArray *filteredArray = [array filteredArrayUsingPredicate:predicate];