首页 > 其他 > 详细

NSPredicate 的使用(持续更新)

时间:2014-03-18 01:37:38      阅读:485      评论:0      收藏:0      [点我收藏+]

bubuko.com,布布扣

NSPredicate

谓词工具一般用于过滤数组数据,也可用来过滤CoreData查询出的数据.

1). 支持keypath

2). 支持正则表达式

 

在使用之前先新建3个类 Teacher Info Address,详细代码如下

Info.h

bubuko.com,布布扣
#import <Foundation/Foundation.h>

@interface Info : NSObject

@property (nonatomic, strong) NSString *classNum;

@end
bubuko.com,布布扣

Info.m

#import "Info.h"

@implementation Info

@end

Address.h

bubuko.com,布布扣
#import <Foundation/Foundation.h>

@interface Address : NSObject

@property (nonatomic, strong) NSString *detailAddress;

@end
bubuko.com,布布扣

Address.m

#import "Address.h"

@implementation Address

@end

Teacher.h

bubuko.com,布布扣
#import <Foundation/Foundation.h>
#import "Info.h"
#import "Address.h"

@interface Teacher : NSObject

@property (nonatomic, strong) NSString   *name;
@property (nonatomic, strong) Info       *info;
@property (nonatomic, strong) Address    *address;
@property (nonatomic, assign) NSInteger   age;

@end
bubuko.com,布布扣

Teacher.m

bubuko.com,布布扣
#import "Teacher.h"

@implementation Teacher

- (instancetype)init
{
    self = [super init];
    if (self) {
     //此处必须初始化以下对象 _info
= [[Info alloc] init]; _address = [[Address alloc] init]; } return self; } @end
bubuko.com,布布扣

 

初始化数据并添加进数组中

bubuko.com,布布扣
    //初始化数据
    Teacher *teacher1 = [[Teacher alloc] init];
    teacher1.info.classNum         = @"11班";
    teacher1.address.detailAddress = @"海淀区";
    teacher1.name                  = @"L.Y.F.";
    teacher1.age                   = 11;
    
    Teacher *teacher2 = [[Teacher alloc] init];
    teacher2.info.classNum         = @"12班";
    teacher2.address.detailAddress = @"立水桥";
    teacher2.name                  = @"P.K.";
    teacher2.age                   = 20;

    Teacher *teacher3 = [[Teacher alloc] init];
    teacher3.info.classNum         = @"11班";
    teacher3.address.detailAddress = @"万盛路";
    teacher3.name                  = @"Y.X.";
    teacher3.age                   = 22;
    
    //将数据添加进数组
    NSMutableArray *teachers =
        [[NSMutableArray alloc] initWithObjects:teacher1, teacher2, teacher3, nil];
bubuko.com,布布扣

开始正式的使用谓词

[1] 比较操作 (>,<,>=,<=,=)

bubuko.com,布布扣

[2] 字符串常规操作 (beginswith,endswith,contains)

    @"name beginswith[cd] ‘Y‘"
    @"name endswith[cd] ‘X.‘"
    @"name contains[cd] ‘X‘"

bubuko.com,布布扣

[3] 范围 (between,in)

    @"age between {10, 20}"
    @"age in {10, 20}" //这个不确定是什么

bubuko.com,布布扣

[4] 通配符 (like)

注:使用?表示一个字符,*表示多个字符

    @"name like[cd] ‘*X*‘"

bubuko.com,布布扣

[5] 逻辑运算 (AND,OR,NOT)

@"age <= 22 AND name like[cd] ‘*X*‘"

bubuko.com,布布扣

[6] 正则表达式

注:^Y.+.$ 以Y开头,以.结尾的字符

    @"self.name matches ‘^Y.+.$‘"

bubuko.com,布布扣

[7] keypath

bubuko.com,布布扣

NSPredicate 的使用(持续更新),布布扣,bubuko.com

NSPredicate 的使用(持续更新)

原文:http://www.cnblogs.com/YouXianMing/p/3605355.html

(0)
(0)
   
举报
评论 一句话评论(0
关于我们 - 联系我们 - 留言反馈 - 联系我们:wmxa8@hotmail.com
© 2014 bubuko.com 版权所有
打开技术之扣,分享程序人生!