CoreData教学完整版（封装我们自己的CoreData工具）_Dylan

2019-11-14 19:59:46

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1. 今天的课程、大家在学习之后肯定会有另一番想法、

至少、你们会收藏我的博客吧、嘿嘿、新开的人气可不怎么高

2. 好、废话不多说、直接切入正题、网上讲coreData的有好多、但大多数不怎么细致、也不会完整的敲代码、

所以、今天上午我自己简单的封装一下coreData供自己使用。大家可以借鉴一下。又不足之处还望指出。

3. 开始编码：

　　1. 导入 coreData.FrameWork 我们今天封装的东西、不实用系统自带的coreData、而是导入库自己去写。加深印象

　　思想：单例 + 中间层（中间层继承于NSManagedObject 方便我们操作、也有住于在业务量大的时候优化代码）

　　总共4个文件我们开始编码：

　　1、单例 ADCoreData.h

 1 // 2 //  ADCoreData.h 3 //  CoreData_CE 4 // 5 //  Created by Dylan on 14-10-11. 6 //  Copyright (c) 2014年 Dylan. All rights reserved. 7 // 8  9 /*!10  *  @Author Dylan.11  *12  *  Please add CoreData.FrameWork13  */14 15 #import <Foundation/Foundation.h>16 #import <CoreData/CoreData.h>17 18 @interface ADCoreData : NSObject19 20 /*!21  *  @Author Dylan.22  *23  *  context24  */25 @PRoperty (nonatomic, strong, readonly) NSManagedObjectContext * manageContext;26 27 + (instancetype)shareInstanceWithStoreName: (NSString *)storeName;28 29 /*!30  *  @Author Dylan.31  *32  *  Methods33  */34 35 - (NSMutableArray *)findByModel: (id)model;36 - (NSMutableArray *)findByModel: (id)model37                    predicateString: (NSString *)predicateString;38 /*!39  *  Update40  */41 - (BOOL)create: (id)model;42 43 - (BOOL)remove: (id)model;44 - (BOOL)remove: (id)model45       predicateString: (NSString *)predicateString;46 - (BOOL)modify: (id)model47  predicateString: (NSString *)predicateString;48 49 @end

　　ADCoreData.m

  1 //  2 //  ADCoreData.m  3 //  CoreData_CE  4 //  5 //  Created by Dylan on 14-10-11.  6 //  Copyright (c) 2014年 Dylan. All rights reserved.  7 //  8   9 #import "ADCoreData.h" 10 #import "ADCoreDataManager.h" 11 #import <objc/runtime.h> 12  13 #define CLASS_NAME(PRAM) NSStringFromClass([PRAM class]) 14  15 @interface ADCoreData () 16  17 @property (nonatomic, strong) NSManagedObjectModel * managedobjectModel; 18 @property (nonatomic, strong) NSPersistentStoreCoordinator * persistentStoreCoordinator; 19  20 /*! 21  *  @Author Dylan. 22  * 23  *  storeName 24  */ 25 @property (nonatomic, strong) NSString * storeName; 26  27 - (NSURL *)applicationDomainUrl; 28  29 @end 30  31 static ADCoreData * coreData; 32  33 @implementation ADCoreData 34  35 + (instancetype)shareInstanceWithStoreName:(NSString *)storeName { 36     static dispatch_once_t onceToken; 37     dispatch_once(&onceToken, ^{ 38         coreData = [[self alloc] init]; 39         coreData.storeName = storeName; 40     }); 41      42     return coreData; 43 } 44  45 /*! 46  *  @Author Dylan. 47  * 48  *  synthesize 49  */ 50 @synthesize manageContext = _manageContext; 51 @synthesize managedobjectModel = _managedobjectModel; 52 @synthesize persistentStoreCoordinator = _persistentStoreCoordinator; 53  54 #pragma mark - 55 #pragma mark - GET 56 - (NSManagedObjectContext *)manageContext { 57      58     if (_manageContext) { 59         return _manageContext; 60     } 61      62     NSPersistentStoreCoordinator * coordinator = [self persistentStoreCoordinator]; 63     if (coordinator != nil) { 64         _manageContext = [[NSManagedObjectContext alloc] init]; 65         [_manageContext setPersistentStoreCoordinator:coordinator]; 66     } 67     return _manageContext; 68 } 69  70 - (NSPersistentStoreCoordinator *)persistentStoreCoordinator { 71      72     if (_persistentStoreCoordinator) { 73         return _persistentStoreCoordinator; 74     } 75      76     NSURL * storeUrl = [[self applicationDomainUrl] URLByAppendingPathComponent:[NSString stringWithFormat:@"%@.sqlite", _storeName]]; 77     _persistentStoreCoordinator = [[NSPersistentStoreCoordinator alloc] initWithManagedObjectModel:self.managedobjectModel]; 78     [_persistentStoreCoordinator addPersistentStoreWithType:NSSQLiteStoreType configuration:nil URL:storeUrl options:nil error:nil]; 79     return _persistentStoreCoordinator; 80 } 81  82 - (NSManagedObjectModel *)managedobjectModel { 83      84     if (_managedobjectModel) { 85         return _managedobjectModel; 86     } 87      88     NSURL * modelUrl = [[NSBundle mainBundle] URLForResource:_storeName withExtension:@"momd"]; 89     _managedobjectModel = [[NSManagedObjectModel alloc] initWithContentsOfURL:modelUrl]; 90     return _managedobjectModel; 91 } 92  93 #pragma mark - Methods 94 - (NSMutableArray *)findByModel: (id)model { 95      96     NSError * error = nil; 97     NSArray * listArray = [_manageContext executeFetchRequest:[self bindRequest:CLASS_NAME(model) predicate:nil] error:&error]; 98     NSMutableArray * resultArray = [NSMutableArray array]; 99     100     for (ADCoreDataManager * manager in listArray) {101         102         for (NSString * propertyName in [self ClassAttributes:model]) {103             [model setValue:[manager valueForKey:propertyName] forKey:propertyName];104         }105         [resultArray addObject:model];106     }107     return resultArray;108 }109 110 - (NSMutableArray *)findByModel: (id)model111                 predicateString: (NSString *)predicateString; {112     113     NSError * error = nil;114     NSArray * listArray = [_manageContext executeFetchRequest:[self bindRequest:CLASS_NAME(model) predicate:predicateString] error:&error];115     NSMutableArray * resultArray = [NSMutableArray array];116     117     if (listArray.count >= 1) {118         for (ADCoreDataManager * manager in listArray) {119             120             for (NSString * propertyName in [self ClassAttributes:model]) {121                 [model setValue:[manager valueForKey:propertyName] forKey:propertyName];122             }123             [resultArray addObject:model];124         }125     }126     return resultArray;127 }128 129 #pragma mark update130 - (BOOL)create: (id)model {131     ADCoreDataManager * manager = [NSEntityDescription insertNewObjectForEntityForName:CLASS_NAME(model) inManagedObjectContext:_manageContext];132     133     for (NSString * propertyName in [self ClassAttributes:model]) {134         [manager setValue:[model valueForKey:propertyName] forKey:propertyName];135     }136     BOOL result = [self saveContext];137     return result;138 }139 140 - (BOOL)remove: (id)model {141     142     NSError * error = nil;143     NSArray * listArray = [_manageContext executeFetchRequest:[self bindRequest:CLASS_NAME(model) predicate:nil] error:&error];144     if (listArray.count > 0) {145         for (ADCoreDataManager * manager in listArray) {146             [_manageContext deleteObject:manager];147         }148     }149     return [self saveContext];150 }151 152 - (BOOL)remove: (id)model153 predicateString: (NSString *)predicateString {154     155     NSError * error = nil;156     NSArray * listArray = [_manageContext executeFetchRequest:[self bindRequest:CLASS_NAME(model) predicate:predicateString] error:&error];157     158     if (listArray.count > 0) {159         for (ADCoreDataManager * manager in listArray) {160             [_manageContext deleteObject:manager];161         }162     }163     return [self saveContext];164 }165 166 - (BOOL)modify: (id)model167  predicateString: (NSString *)predicateString {168     169     NSError * error = nil;170     NSArray * listArray = [_manageContext executeFetchRequest:[self bindRequest:CLASS_NAME(model) predicate:predicateString] error:&error];171     172     if (listArray.count > 0) {173         174         for (ADCoreDataManager * manager in listArray) {175             for (NSString * propertyName in [self ClassAttributes:model]) {176                 [manager setValue:[model valueForKey:propertyName] forKey:propertyName];177             }178         }179     }180     return [self saveContext];181 }182 183 #pragma mark - collect184 - (NSFetchRequest *)bindRequest: (NSString *)className185           predicate: (NSString *)predicateString {186     NSFetchRequest * request = [[NSFetchRequest alloc] init];187     [request setEntity:[NSEntityDescription entityForName:className inManagedObjectContext:_manageContext]];188     189     if (predicateString != nil) {190         NSPredicate * predicate = [NSPredicate predicateWithFormat:predicateString];191         NSLog(@"%@", predicate);192         NSLog(@"%@", predicateString);193         [request setPredicate:predicate];194     }195     return request;196 }197 198 199 #pragma mark - save200 - (BOOL)saveContext {201     202     NSManagedObjectContext * context = [self manageContext];203     if (context != nil) {204         205         NSError * error = nil;206         if ([context hasChanges] && ![context save:&error]) {207             NSLog(@"%@", [error userInfo]);208             abort();209             return NO;210         }211     }212     213     return YES;214 }215 216 217 - (NSURL *)applicationDomainUrl {218     return [[[NSFileManager defaultManager] URLsForDirectory:NSDocumentDirectory inDomains:NSUserDomainMask] lastObject];219 }220 221 #pragma mark - allAttributes222 - (NSMutableArray *) ClassAttributes: (id)classModel {223     224     NSMutableArray * array = [NSMutableArray array];225     NSString *className = NSStringFromClass([classModel class]);226     const char * cClassName = [className UTF8String];227     228     id classM = objc_getClass(cClassName);229     unsigned int outCount, i;230     objc_property_t * properties = class_copyPropertyList(classM, &outCount);231     for (i = 0; i < outCount; i++) {232         objc_property_t property = properties[i];233         NSString * attributeName = [NSString stringWithUTF8String:property_getName(property)];234         235         [array addObject:attributeName];236     }237     return array;238 }239 240 @end

　　在m文件中，我使用了运行时。运行时拿到一个模型的属性这样我们可以更加方便的使用KVC

　　大家仔细看一下这种封装的过程　　

2.中间层： ADCoreDataManager.h

 1 // 2 //  ADCoreDataManager.h 3 //  CoreData_CE 4 // 5 //  Created by Dylan on 14-10-11. 6 //  Copyright (c) 2014年 Dylan. All rights reserved. 7 // 8  9 #warning add Model properties Here10 11 #import <CoreData/CoreData.h>12 #import <Foundation/Foundation.h>13 14 @interface ADCoreDataManager : NSManagedObject15 16 /*!17  *  @Author Dylan.18  *19  *  e.g20  */21 @property (nonatomic, strong) NSString * name;22 23 @end

　　.m文件

 1 // 2 //  ADCoreDataManager.m 3 //  CoreData_CE 4 // 5 //  Created by Dylan on 14-10-11. 6 //  Copyright (c) 2014年 Dylan. All rights reserved. 7 // 8  9 #warning don't forget write @synthesize10 11 #import "ADCoreDataManager.h"12 13 @implementation ADCoreDataManager14 15 @synthesize name = _name;16 17 - (void)setValue:(id)value forUndefinedKey:(NSString *)key {18     19 }20 21 @end

　　大家可以把所有模型的属性扔到中间层里边。使用中间层去做中介传值。

　　使用：

　　1. 创建自己的momd文件。新建-》coredata-》model 创建之后添加模型

　　2. 初始化单例

　　附上测试代码

 1 // test 2     ADCoreData * coreData = [ADCoreData shareInstanceWithStoreName:@"CoreData"]; 3      4     Dylan * dylan = [[Dylan alloc] initWithEntity:[NSEntityDescription entityForName:@"Dylan" inManagedObjectContext:coreData.manageContext] insertIntoManagedObjectContext:nil]; 5     [dylan setName:@"Dylan"]; 6      7     NSLog(@"**************************************************"); 8      9     NSLog(@"first = %@", [coreData findByModel:dylan]);10     11     NSLog(@"**************************************************");12     13     [coreData create:dylan];14     NSLog(@"second = %@", [coreData findByModel:dylan]);15     NSLog(@"third = %@", [coreData findByModel:dylan predicateString:@"name = 'Dylan'"]);16     NSLog(@"**************************************************");17     18     [coreData remove:dylan];19     NSLog(@"fourth = %@", [coreData findByModel:dylan]);20     NSLog(@"**************************************************");21     22     [coreData create:dylan];23     NSLog(@"fifth = %@", [coreData findByModel:dylan]);24     25     NSLog(@"**************************************************");26     27     Dylan * dylan1 = [[Dylan alloc] initWithEntity:[NSEntityDescription entityForName:@"Dylan" inManagedObjectContext:coreData.manageContext] insertIntoManagedObjectContext:nil];28     dylan1.name = @"dylan-1";29     30     [coreData modify:dylan1 predicateString:nil];31     NSLog(@"sixth = %@", [coreData findByModel:dylan]);32     NSLog(@"seventh = %@", [coreData findByModel:dylan1]);