ios中文件从Bundle目录拷贝到Document目录下面的正确方法

//_______数据库临时获取_________

NSArray *path = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *docDirectory = [path objectAtIndex:0];
NSString *filePath = [[NSBundle mainBundle] pathForResource:@"car_business" ofType:@"db"];
NSString *dstPath = [docDirectory stringByAppendingPathComponent:@"car_business.db"];
NSLog(@"%@",filePath);
[[NSFileManager defaultManager] copyItemAtPath:filePath toPath:dstPath error:nil];