一、首先创建一个coreData 模型文件
(如:CoreDataTestModel.xcdatamodeld)
二、创建Model(实体):XLTestModel
XLTestModel.h
@interface XLTestModel : NSObject
@property (nonatomic, copy) NSString *school;
@property (nonatomic, copy) NSString *name;
@property (nonatomic, assign) NSInteger age;
@property (nonatomic, copy) NSString *recordId;
@end
XLTestModel.m
@implementation XLTestModel
@end
三、创建Entity(实例):(XLTestEntity)
(一)、图示
(二)四个文件:
1、配置Entity的属性
2、要设置CoreData的Tool Version:(建议手动可以,随时查看定位)
<1>手动生成管理,2个分类(CoreDataProperties、CoreDataClass)
在Xcode7及以前时代,手动管理,生成2个分类4个文件
XLTestEntity+CoreDataProperties.h
#import "XLTestEntity+CoreDataClass.h"
@interface XLTestEntity (CoreDataProperties)
+ (NSFetchRequest<XLTestEntity *> *)fetchRequest;
@property (nullable, nonatomic, copy) NSString *school;
@property (nullable, nonatomic, copy) NSString *name;
@property (nonatomic) int64_t age;
@property (nullable, nonatomic, copy) NSString *recordId;
@property (nullable, nonatomic, copy) NSString *mySelfID;
@end
XLTestEntity+CoreDataClass.m
@implementation XLTestEntity (CoreDataProperties)
+ (NSFetchRequest<XLTestEntity *> *)fetchRequest {
return [NSFetchRequest fetchRequestWithEntityName:@"XLTestEntity"];
}
@dynamic school;
@dynamic name;
@dynamic age;
@dynamic recordId;
@dynamic mySelfID;
@end
XLTestEntity+CoreDataClass.h
#import <Foundation/Foundation.h>
#import <CoreData/CoreData.h>
@interface XLTestEntity : NSManagedObject
@end
#import "XLTestEntity+CoreDataProperties.h"
XLTestEntity+CoreDataClass.m
#import "XLTestEntity+CoreDataClass.h"
@implementation XLTestEntity
@end
<2>自动生成管理,在Xcode8及以后版本,封禁掉自动生成代码,自动管理。<3>设置语言,swift(默认),选择objective-c,需要手动修改
四、创建CoreData管理类(CoreDataManager)
CoreDataManager.h
#import <Foundation/Foundation.h>
#import <CoreData/CoreData.h>
//实体model
#import "XLTestModel.h"
//实例class
#import "XLTestEntity+CoreDataClass.h"
#import "XLTestEntity+CoreDataClass.h"
NS_ASSUME_NONNULL_BEGIN
@interface CoreDataManager : NSObject
/*1.
NSManagedObjectContext(被管理的数据上下文)
操作实际内容(操作持久层)
作用:插入数据,查询数据,删除数据
*/
@property (readonly, strong, nonatomic) NSManagedObjectContext *managedObjectContext;
/*2.
NSManagedObjectModel(被管理的数据模型)
数据库所有表格或数据结构,包含各实体的定义信息
作用:添加实体的属性,建立属性之间的关系
操作方法:视图编辑器,或代码
*/
@property (readonly, strong, nonatomic) NSManagedObjectModel *managedObjectModel;
/*3.
NSPersistentStoreCoordinator(持久化存储助理)
相当于数据库的连接器
作用:设置数据存储的名字,位置,存储方式,和存储时机
*/
@property (readonly, strong, nonatomic) NSPersistentStoreCoordinator *persistentStoreCoordinator;
/*
(4)NSManagedObject(被管理的数据记录)
相当于数据库中的表格记录
(5)NSFetchRequest(获取数据的请求)
相当于查询语句
(6)NSEntityDescription(实体结构)
相当于表格结构
(7)后缀为.xcdatamodeld的包
里面是.xcdatamodel文件,用数据模型编辑器编辑
编译后为.momd或.mom文件
*/
+ (CoreDataManager*)shareCoreDataManager;
- (void)insertModelWithMySelfID:(NSString *)mySelfID WithModel:(XLTestModel *)model;//增
- (NSArray *)getDataWithMySelfID:(NSString *)mySelfID;//查
- (void)updateModelWithMySelfID:(NSString *)mySelfID WithModel:(XLTestModel *)model;//改
- (void)deletModelWithMySelfID:(NSString *)mySelfID WithModel:(XLTestModel *)model;//删一个
- (void)deleteAllModelWithMySelfID:(NSString *)mySelfID;//删所有
@end
NS_ASSUME_NONNULL_END
CoreDataManager.m
#import "CoreDataManager.h"
@implementation CoreDataManager
@synthesize managedObjectContext = _managedObjectContext;
@synthesize managedObjectModel = _managedObjectModel;
@synthesize persistentStoreCoordinator = _persistentStoreCoordinator;
+ (CoreDataManager *)shareCoreDataManager {
static CoreDataManager *coreDataManager;
static dispatch_once_t onceToken;
dispatch_once(&onceToken, ^{
coreDataManager = [[CoreDataManager alloc] init];
});
return coreDataManager;
}
- (void)saveContext {
NSError *error = nil;
NSManagedObjectContext *managedObjectContext = self.managedObjectContext;
if (managedObjectContext != nil) {
if ([managedObjectContext hasChanges] && ![managedObjectContext save:&error]) {
NSLog(@"Unresolved error %@, %@", error, [error userInfo]);
abort();
}
}
}
#pragma mark - Core Data stack
- (NSManagedObjectContext *)managedObjectContext {
if (_managedObjectContext != nil) {
return _managedObjectContext;
}
NSPersistentStoreCoordinator *coordinator = [self persistentStoreCoordinator];
if (coordinator != nil) {
_managedObjectContext = [[NSManagedObjectContext alloc] initWithConcurrencyType:NSMainQueueConcurrencyType];
[_managedObjectContext setPersistentStoreCoordinator:coordinator];
}
return _managedObjectContext;
}
- (NSManagedObjectModel *)managedObjectModel {
if (_managedObjectModel != nil) {
return _managedObjectModel;
}
NSURL *modelURL = [[NSBundle mainBundle] URLForResource:@"CoreDataTestModel" withExtension:@"momd"];
_managedObjectModel = [[NSManagedObjectModel alloc] initWithContentsOfURL:modelURL];
return _managedObjectModel;
}
- (NSPersistentStoreCoordinator *)persistentStoreCoordinator {
if (_persistentStoreCoordinator != nil) {
return _persistentStoreCoordinator;
}
NSURL *storeURL = [[self applicationDocumentsDirectory] URLByAppendingPathComponent:@"xiaoliCoreData.sqlite"];
NSError *error = nil;
/*
*配置支持 低版本数据库向高版本数据库迁移
NSMigratePersistentStoresAutomaticallyOption设置为YES,CoreData会试着把低版本的持久化存储区迁移到最新版本的模型文件。
NSInferMappingModelAutomaticallyOption设置为YES,CoreData会试着以最为合理地方式自动推断出源模型文件的实体中,某个属性到底对应于目标模型文件实体中的哪一个属性。
*/
//设置版本迁移方案
NSDictionary *options = @{NSMigratePersistentStoresAutomaticallyOption:@(YES),NSInferMappingModelAutomaticallyOption:@(YES)};
_persistentStoreCoordinator = [[NSPersistentStoreCoordinator alloc] initWithManagedObjectModel:[self managedObjectModel]];
// 创建持久化存储协调器,并将迁移方案的字典当做参数传入
if (![_persistentStoreCoordinator addPersistentStoreWithType:NSSQLiteStoreType configuration:nil URL:storeURL options:options error:&error]) {
NSLog(@"Unresolved error %@, %@", error, [error userInfo]);
abort();
}
return _persistentStoreCoordinator;
}
// 返回应用程序 存储目录的URL
- (NSURL *)applicationDocumentsDirectory {
return [[[NSFileManager defaultManager] URLsForDirectory:NSDocumentDirectory inDomains:NSUserDomainMask] lastObject];
}
- (void)insertModelWithMySelfID:(NSString *)mySelfID WithModel:(XLTestModel *)model {//增
NSManagedObjectContext *context = [self managedObjectContext];
NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] initWithEntityName:@"XLTestEntity"];
//谓词---过滤(表名+关系名)
fetchRequest.predicate = [NSPredicate predicateWithFormat:@"(mySelfID == %@ and name == %@)",mySelfID ,model.recordId];
NSError *error;
NSInteger count = [context countForFetchRequest:fetchRequest error:&error];
if (count < 1) {
XLTestEntity *myCollect = [NSEntityDescription insertNewObjectForEntityForName:@"XLTestEntity" inManagedObjectContext:context];
myCollect.mySelfID = mySelfID;
myCollect.school = model.school;
myCollect.name = model.name;
myCollect.age = model.age;
myCollect.recordId = model.recordId;
NSError *error;
if (![context save:&error]) {
NSLog(@"保存失败:%@",error);
}
}
}
- (NSArray *)getDataWithMySelfID:(NSString *)mySelfID {//查
NSMutableArray *myCollects = [[NSMutableArray alloc] init];
NSManagedObjectContext *context = [self managedObjectContext];
NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] initWithEntityName:@"XLTestEntity"];
fetchRequest.predicate = [NSPredicate predicateWithFormat:@"(mySelfID == %@)",mySelfID];
NSError *error;
NSArray *fetchRequestObjects = [context executeFetchRequest:fetchRequest error:&error];
for (XLTestEntity *myCollect in fetchRequestObjects) {
XLTestModel *model = [XLTestModel new];
model.school = myCollect.school;
model.name = myCollect.name;
model.age = myCollect.age;
model.recordId = myCollect.recordId;
[myCollects addObject:model];
}
return myCollects;
}
- (void)updateModelWithMySelfID:(NSString *)mySelfID WithModel:(XLTestModel *)model{//改
NSManagedObjectContext *context = [self managedObjectContext];
NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] initWithEntityName:@"XLTestEntity"];
fetchRequest.predicate = [NSPredicate predicateWithFormat:@"(mySelfID == %@ and recordId == %@)",mySelfID ,model.recordId];
NSError *error;
NSArray *fetchRequestObjects = [context executeFetchRequest:fetchRequest error:&error];
if (!error) {
if (fetchRequestObjects.count == 1) {
XLTestEntity *myCollect = fetchRequestObjects[0];
myCollect.school = model.school;
myCollect.name = model.name;
myCollect.age = model.age;
}
}
if ([context hasChanges]) {
if (![context save:&error]) {
NSLog(@"更改失败:%@",error);
}
}
}
- (void)deletModelWithMySelfID:(NSString *)mySelfID WithModel:(XLTestModel *)model {//删一个
NSManagedObjectContext *context = [self managedObjectContext];
NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] initWithEntityName:@"XLTestEntity"];
fetchRequest.predicate = [NSPredicate predicateWithFormat:@"(mySelfID == %@ and recordId == %@)",mySelfID ,model.recordId];
NSError *error;
NSArray *fetchedObjects = [context executeFetchRequest:fetchRequest error:&error];
if (!error) {
for (XLTestEntity *myCollect in fetchedObjects) {
[context deleteObject:myCollect];
}
}
if ([context hasChanges]) {
if (![context save:&error]) {
NSLog(@"删除失败:%@",error);
}
}
}
- (void)deleteAllModelWithMySelfID:(NSString *)mySelfID; {//删所有
NSManagedObjectContext *context = [self managedObjectContext];
NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] initWithEntityName:@"XLTestEntity"];
fetchRequest.predicate = [NSPredicate predicateWithFormat:@"(mySelfID == %@)",mySelfID];
NSError *error;
NSArray *fetchedObjects = [context executeFetchRequest:fetchRequest error:&error];
if (!error) {
for (XLTestEntity *myCollect in fetchedObjects) {
[context deleteObject:myCollect];
}
}
if ([context hasChanges]) {
if (![context save:&error]) {
NSLog(@"删除失败:%@",error);
}
}
}
@end
五、具体实现
//增
for (NSInteger i=0; i<4; i++) {
XLTestModel *model = [XLTestModel new];
model.name = [NSString stringWithFormat:@"张%ld", i];
model.school = @"第一中学";
model.age = 20+i;
model.recordId = [NSString stringWithFormat:@"record_%ld", i+1000];
[[CoreDataManager shareCoreDataManager] insertModelWithMySelfID:@"xiaoli" WithModel:model];
}
//查
NSArray *arr0 = [[CoreDataManager shareCoreDataManager] getDataWithMySelfID:@"xiaoli"];
NSLog(@"%@", arr0);
//改
XLTestModel *model1 = [XLTestModel new];
model1.name = @"王二";
model1.school = @"第-中学";
model1.age = 30;
model1.recordId = @"record_1000";
[[CoreDataManager shareCoreDataManager] updateModelWithMySelfID:@"xiaoli" WithModel:model1];
NSArray *arr1 = [[CoreDataManager shareCoreDataManager] getDataWithMySelfID:@"xiaoli"];
NSLog(@"%@", arr1);
//删一个
XLTestModel *model2 = [XLTestModel new];
model2.recordId = @"record_1003";
[[CoreDataManager shareCoreDataManager] deletModelWithMySelfID:@"xiaoli" WithModel:model2];
NSArray *arr2 = [[CoreDataManager shareCoreDataManager] getDataWithMySelfID:@"xiaoli"];
NSLog(@"%@", arr2);
//删所有
[[CoreDataManager shareCoreDataManager] deleteAllModelWithMySelfID:@"xiaoli"];
NSArray *arr3 = [[CoreDataManager shareCoreDataManager] getDataWithMySelfID:@"xiaoli"];
NSLog(@"%@", arr3);