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NSMutableArray iPhone的核心数据实体属性值_Iphone_Objective C_Ios_Core Data - Fatal编程技术网

NSMutableArray iPhone的核心数据实体属性值

NSMutableArray iPhone的核心数据实体属性值,iphone,objective-c,ios,core-data,Iphone,Objective C,Ios,Core Data,我正在使用此代码获取核心数据结果: -(void)getData { NSEntityDescription *entity = [NSEntityDescription entityForName:@"Favouritesdata" inManagedObjectContext:context]; NSFetchRequest *request = [[NSFetchRequest alloc] init]; [request setFetchBatchSize:20]; [reque

我正在使用此代码获取核心数据结果:

-(void)getData {

NSEntityDescription *entity = [NSEntityDescription entityForName:@"Favouritesdata" inManagedObjectContext:context];

NSFetchRequest *request = [[NSFetchRequest alloc] init];

[request setFetchBatchSize:20];

[request setEntity:entity];

NSSortDescriptor *sort = [[NSSortDescriptor alloc] initWithKey:@"licenseplate" ascending:NO];

NSArray *newArray = [[NSArray alloc]initWithObjects:sort, nil];

[request setSortDescriptors:newArray];

NSError *error;
results = [[context executeFetchRequest:request error:&error] mutableCopy];

NSLog(@"results::::: %@", results);

[self setLicensePlateArray:results];

[self.favouritesTable reloadData];

}
在这个实体FavoriteSdata中,我有一个名为license plate的属性,我想将这个属性值传递给NSMutableArray


如何获取这些值?

您可以使用NSPredicate并通过在请求中传递谓词直接获取值。有关初学者难以理解的更多信息,请参阅此链接。。。任何教程或示例代码请参考此链接并转到保存和加载部分,您将找到somr coredata教程。对于NSFetchController教程将有所帮助。NSEntityDescription*EntityDescription=[NSEntityDescription entityForName:@“Contacts”在ManagedObjectContext:context中];NSFetchRequest*request=[[NSFetchRequest alloc]init];[请求集合实体:entityDesc];NSPredicate*pred=[NSPredicate谓词格式:@“(name=%@)”,name.text];[请求集谓词:pred];