一.创建两个Model
Model.h
#import@interface Model : NSObject
@property(nonatomic,strong)NSString *name,*age;
@end
Model1.h
#import "Model.h"
#import "Entity+CoreDataClass.h"
@interface Model1 : NSObject
//单例类
+(instancetype)shareLoadData;
//添加数据
-(void)insertData:(Model *)myAu;
//修改数据
-(void)updateData;
//删除数据
-(void)deleteData:(Entity *)au;
//查询所有数据
-(NSArray *)getAllData;
@end
Model1.m
#import <CoreData/CoreData.h>
#import "Model1.h"
#import "AppDelegate.h"
static Model1 *ld;
@implementation Model1
//单例类
+(instancetype)shareLoadData{
if (!ld) {
ld = [[Model1 alloc]init];
}
return ld;
}
+(instancetype)allocWithZone:(struct _NSZone *)zone{
if (!ld) {
ld = [super allocWithZone:zone];
}
return ld;
}
-(id)copy{
return self;
}
-(id)mutableCopy{
return self;
}
//增加
-(void)insertData:(Model *)myAu{
AppDelegate *app = (AppDelegate *)[UIApplication sharedApplication].delegate;
//创建一个实体对象
Entity *au = [NSEntityDescription insertNewObjectForEntityForName:@"Entity" inManagedObjectContext:app.persistentContainer.viewContext];
//给实体对象复制
au.name = myAu.name;
au.age = myAu.age;
//保存 （增删改）
[app saveContext];
}
//修改数据
-(void)updateData{
AppDelegate *app = (AppDelegate *)[UIApplication sharedApplication].delegate;
//保存 （增删改）
[app saveContext];
}
//删除数据
-(void)deleteData:(Entity *)au{
AppDelegate *app = (AppDelegate *)[UIApplication sharedApplication].delegate;
//删除信息
[app.persistentContainer.viewContext deleteObject:au];
//保存 （增删改）
[app saveContext];
}
//查询所有数据
-(NSArray *)getAllData{
AppDelegate *app = (AppDelegate *)[UIApplication sharedApplication].delegate;
//初始化一个抓取请求的对象
NSFetchRequest *request =[[NSFetchRequest alloc]init];
//初始化一个实体
NSEntityDescription *newAu = [NSEntityDescription entityForName:@"Entity" inManagedObjectContext:app.persistentContainer.viewContext];
//设置抓取请求
[request setEntity:newAu];
//查询数据
NSArray *arr = [app.persistentContainer.viewContext executeFetchRequest:request error:nil];
return arr;
}
@end
