從coredata對象讀取

Question

我正在嘗試獲取保存到核心數據對象中的值，但是卻出現此錯誤

Use of undeclared identifier 'error'

這指向我在下面的代碼和平中反省和錯誤的地方

// Test listing all FailedBankInfos from the store
        NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init];
        NSEntityDescription *entity = [NSEntityDescription entityForName:@"Manuf" inManagedObjectContext:context];
        [fetchRequest setEntity:entity];

NSArray *fetchedObjects = [context executeFetchRequest:fetchRequest error:&error];
        for (Manuf *manuf in fetchedObjects) {

           // Log all of the values in the object  

        }

任何幫助，將不勝感激

Answer 1

您需要先聲明錯誤，然后再傳遞對它在executeFetchRequest位置的executeFetchRequest 。

像這樣：

NSError *error;