Coredata 单表简单使用

 1 //
 2 //  ViewController.m
 3 //  Coredatanpp
 4 //
 5 //  Created by Z_小圣 on 2019/3/19.
 6 //  Copyright © 2019年 奶瓶瓶. All rights reserved.
 7 //
 8 
 9 #import "ViewController.h"
10 #import "BabyModal.h"
11 #import "AppDelegate.h"
12 @interface ViewController ()
13 {
14     NSManagedObjectContext *_context;
15     NSPersistentContainer *_container;
16     NSManagedObjectModel *_managedObjectModel;
17 }
18 @end
19 
20 @implementation ViewController
21 
22 - (void)viewDidLoad {
23     [super viewDidLoad];
24     AppDelegate * appDelegate = (AppDelegate *)[UIApplication sharedApplication].delegate;
25      _container = appDelegate.persistentContainer;
26     //返回沙盒中存储数据库的文件夹URL路径，这是一个静态方法，表示数据库的文件路径是唯一的
27     NSURL * url = [NSPersistentContainer defaultDirectoryURL];
28     NSLog(@"沙盒路径%@",url);
29     _context = _container.viewContext;
30     _managedObjectModel = _container.managedObjectModel;
31     // Do any additional setup after loading the view, typically from a nib.
32 }
33 //添加方法
34 - (IBAction)addAction:(UIButton *)sender {
35     // 1.创建一个新的继承于NSManagedObject的子类BabyModal
36     BabyModal *baby = [NSEntityDescription  insertNewObjectForEntityForName:@"Baby"  inManagedObjectContext:_context];
37 
38     //2.根据表Baby中的键值，给NSManagedObject对象赋值
39     baby.name = [NSString stringWithFormat:@"长江-%d",arc4random()%100];
40     baby.age = arc4random()%20;
41     baby.gender = arc4random()%2 == 0 ?  0: 1;
42     
43 //       3.保存插入的数据
44     NSError *error = nil;
45     if ([_context save:&error]) {
46         NSLog(@"数据插入到数据库成功");
47     }else{
48         NSLog(@"数据插入到数据库失败,%@",error);
49     }
50     
51 }
52 //查询方法
53 - (IBAction)queryAction:(UIButton *)sender {
54     
55     //创建查询请求
56     NSFetchRequest *request = [NSFetchRequest fetchRequestWithEntityName:@"Baby"];
57     //查询条件
58     NSPredicate *pre = [NSPredicate predicateWithFormat:@"gender = %@", @"0"];
59     request.predicate = pre;
60     // 从第几页开始显示
61     // 通过这个属性实现分页
62     //request.fetchOffset = 0;
63     // 每页显示多少条数据
64     //request.fetchLimit = 6;
65     //发送查询请求
66     NSArray *resArray = [_context executeFetchRequest:request error:nil];
67     //打印查询数据
68     for (BabyModal *modal in resArray ) {
69         NSLog(@"查询结果:姓名=%@ ，年龄=%ld ，性别=%@",modal.name,modal.age,[NSString stringWithFormat:@"%d",modal.gender]);
70     }
71 }
72 //删除方法
73 - (IBAction)deleteAction:(UIButton *)sender {
74     //创建删除请求
75     NSFetchRequest *deleRequest = [NSFetchRequest fetchRequestWithEntityName:@"Baby"];
76     //删除条件
77     NSPredicate *pre = [NSPredicate predicateWithFormat:@"age < %d", 10];
78     deleRequest.predicate = pre;
79     //返回需要删除的对象数组
80     NSArray *deleArray = [_context executeFetchRequest:deleRequest error:nil];
81     //从数据库中删除
82     for (BabyModal *stu in deleArray) {
83         [_context deleteObject:stu];
84     }
85     NSError *error = nil;
86     //保存--记住保存
87     if ([_context save:&error]) {
88         NSLog(@"删除 age < 10 的数据");
89     }else{
90         NSLog(@"删除数据失败, %@", error);
91     }
92 }
93 
94 
95 
96 @end

  1 //
  2 //  ViewController.m
  3 //  Coredatanpp
  4 //
  5 //  Created by Z_小圣 on 2019/3/19.
  6 //  Copyright © 2019年 奶瓶瓶. All rights reserved.
  7 //
  8 
  9 #import "ViewController.h"
 10 #import "BabyModal.h"
 11 @interface ViewController ()
 12 {
 13     NSManagedObjectContext *_context;
 14 }
 15 @end
 16 
 17 @implementation ViewController
 18 
 19 - (void)viewDidLoad {
 20     [super viewDidLoad];
 21     [self createSqlite];//创建数据库
 22     // Do any additional setup after loading the view, typically from a nib.
 23 }
 24 //创建数据库
 25 - (void)createSqlite{
 26     
 27     //1、创建模型对象
 28     //获取模型路径 URLForResource参数需要根据创建的Datamodel的名称来
 29     NSURL *modelURL = [[NSBundle mainBundle] URLForResource:@"CoredatanppManual" withExtension:@"momd"];
 30     //根据模型文件创建模型对象
 31     NSManagedObjectModel *model = [[NSManagedObjectModel alloc] initWithContentsOfURL:modelURL];
 32     
 33     //2、创建持久化存储助理：数据库
 34     //利用模型对象创建助理对象
 35     NSPersistentStoreCoordinator *store = [[NSPersistentStoreCoordinator alloc] initWithManagedObjectModel:model];
 36     
 37     //数据库的名称和路径
 38     NSString *docStr = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) lastObject];
 39     NSString *sqlPath = [docStr stringByAppendingPathComponent:@"coreData.sqlite"];
 40     NSLog(@"数据库 path = %@", sqlPath);
 41     NSURL *sqlUrl = [NSURL fileURLWithPath:sqlPath];
 42     
 43     NSError *error = nil;
 44     //设置数据库相关信息 添加一个持久化存储库并设置类型和路径，NSSQLiteStoreType：SQLite作为存储库
 45     [store addPersistentStoreWithType:NSSQLiteStoreType configuration:nil URL:sqlUrl options:nil error:&error];
 46     
 47     if (error) {
 48         NSLog(@"添加数据库失败:%@",error);
 49     } else {
 50         NSLog(@"添加数据库成功");
 51     }
 52     
 53     //3、创建上下文 保存信息 对数据库进行操作
 54     NSManagedObjectContext *context = [[NSManagedObjectContext alloc] initWithConcurrencyType:NSMainQueueConcurrencyType];
 55     
 56     //关联持久化助理
 57     context.persistentStoreCoordinator = store;
 58     _context = context;
 59 }
 60 //添加方法
 61 - (IBAction)addAction:(UIButton *)sender {
 62     // 1.创建一个新的继承于NSManagedObject的子类BabyModal
 63     BabyModal *baby = [NSEntityDescription  insertNewObjectForEntityForName:@"Baby"  inManagedObjectContext:_context];
 64 
 65     //2.根据表Baby中的键值，给NSManagedObject对象赋值
 66     baby.name = [NSString stringWithFormat:@"长江-%d",arc4random()%100];
 67     baby.age = arc4random()%20;
 68     baby.gender = arc4random()%2 == 0 ?  0: 1;
 69     
 70 //       3.保存插入的数据
 71     NSError *error = nil;
 72     if ([_context save:&error]) {
 73         NSLog(@"数据插入到数据库成功");
 74     }else{
 75         NSLog(@"数据插入到数据库失败,%@",error);
 76     }
 77     
 78 }
 79 //查询方法
 80 - (IBAction)queryAction:(UIButton *)sender {
 81     
 82     //创建查询请求
 83     NSFetchRequest *request = [NSFetchRequest fetchRequestWithEntityName:@"Baby"];
 84     //查询条件
 85     NSPredicate *pre = [NSPredicate predicateWithFormat:@"gender = %@", @"0"];
 86     request.predicate = pre;
 87     // 从第几页开始显示
 88     // 通过这个属性实现分页
 89     //request.fetchOffset = 0;
 90     // 每页显示多少条数据
 91     //request.fetchLimit = 6;
 92     //发送查询请求
 93     NSArray *resArray = [_context executeFetchRequest:request error:nil];
 94     //打印查询数据
 95     for (BabyModal *modal in resArray ) {
 96         NSLog(@"查询结果:姓名=%@ ，年龄=%ld ，性别=%@",modal.name,modal.age,[NSString stringWithFormat:@"%d",modal.gender]);
 97     }
 98 }
 99 //删除方法
100 - (IBAction)deleteAction:(UIButton *)sender {
101     //创建删除请求
102     NSFetchRequest *deleRequest = [NSFetchRequest fetchRequestWithEntityName:@"Baby"];
103     //删除条件
104     NSPredicate *pre = [NSPredicate predicateWithFormat:@"age < %d", 10];
105     deleRequest.predicate = pre;
106     //返回需要删除的对象数组
107     NSArray *deleArray = [_context executeFetchRequest:deleRequest error:nil];
108     //从数据库中删除
109     for (BabyModal *stu in deleArray) {
110         [_context deleteObject:stu];
111     }
112     NSError *error = nil;
113     //保存--记住保存
114     if ([_context save:&error]) {
115         NSLog(@"删除 age < 10 的数据");
116     }else{
117         NSLog(@"删除数据失败, %@", error);
118     }
119 }
120 
121 
122 
123 @end