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所有操作都基于Core Data框架相关 API，工程需要添加CoreData.framework支持
1.增 NSEntityDescription insertNewObjectForEntityForName: inManagedObjectContext:
利用NSEntityDescription工厂方法创建Entity
AppDelegate *appDelegate = [UIApplication sharedApplication].delegate; //get NSManagedObjectContext NSManagedObjectContext *context = [appDelegate managedObjectContext]; NSManagedObject *managedObject = nil; managedObject = [NSEntityDescription insertNewObjectForEntityForName:youEntityName inManagedObjectContext:context];//youEntityName is a NSString [managedObject setValue:youKeyValue forKey: youEntityKeyName];//KVO方式赋值value - key //e.g. [managedObject setValue:[name descrition] forKey: @"kEntityKeyName"], the entity must include name property, and its name must be "kEntityKeyName" [appDelegate saveContext];//Don‘t forget to save the changes
2.删 context deleteObject:
NSManagedObject * deleteObject = youWillDeleteObject;//Can get the object from the query result , which is a NSArray getting by the way of using NSFetchRequest
/*e.g.
NSFetchRequest *request = [[NSFetchRequest alloc] initWithEntityName:kEntityName];
NSError *error;
NSArray *objects = [context executeFetchRequest:request error:&error];
//choose one object or many objects
*/
AppDelegate *delegate = [UIApplication sharedApplication].delegate;
NSManagedObjectContext *context = [delegate managedObjectContext];
[context deleteObject:deleteObject];
[delegate saveContext];
3.改 略
4.查
4.1查找全部context executeFetchRequest: error:
NSMutableArray *_array;
AppDelegate *appDelegate = [UIApplication sharedApplication].delegate;
NSManagedObjectContext *context = [appDelegate managedObjectContext];
NSFetchRequest *request = [[NSFetchRequest alloc] initWithEntityName:kEntityName];
NSError *error;
NSArray *objects = [context executeFetchRequest:request error:&error];
if (objects == nil) {
NSLog(@"There is an error!");
}else{
_array = [NSMutableArray arrayWithArray:objects];
}
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原文地址：http://www.cnblogs.com/fortunely/p/4725982.html
