Question

我使用视频教程在Unity中制作游戏，编写了与该教程相同的代码，但是在视频教程中，所有内容都有效，并且代码中有错误。我正在尝试制作可堆叠的库存：

public void AddItem(int id)
{
    Item itemToAdd = database.FetchItemByID(id);

    if (itemToAdd.Stackable && CheckIfItemIsInInventory(itemToAdd))
    {
        for (int i = 0; i < items.Count; i++)
        {
            if (items[i].ID == id)
            {
                ItemData data = slots[i].transform.GetChild(0).GetComponent<ItemData>();
                data.amount++;
                data.transform.GetChild(0).GetComponent<Text>().text = data.amount.ToString();
                break;
            }
        }
    }
    else {
        for (int i = 0; i < items.Count; i++)
        {
            if (items[i].ID == -1)
            {
                items[i] = itemToAdd;
                GameObject itemObj = Instantiate(inventoryItem);
                itemObj.transform.SetParent(slots[i].transform);
                itemObj.transform.position = Vector2.zero;
                itemObj.GetComponent<Image>().sprite = itemToAdd.Sprite;
                itemObj.name = itemToAdd.Title;
                break;
            }
        }
    }
}

当您尝试使用AddItem（id）创建可堆叠对象时；我收到以下错误：

KeyNotFoundException: The given key was not present in the dictionary.
System.Collections.Generic.Dictionary`2[System.String,LitJson.JsonData].get_Item (System.String key) (at /Users/builduser/buildslave/mono/build/mcs/class/corlib/System.Collections.Generic/Dictionary.cs:150)
LitJson.JsonData.get_Item (System.String prop_name)
ItemDatabase.ConstructItemDatabase () (at Assets/Scripts/ItemDatabase.cs:33)
ItemDatabase.Start () (at Assets/Scripts/ItemDatabase.cs:16)

和

NullReferenceException: Object reference not set to an instance of an object
Inventory.AddItem (Int32 id) (at Assets/Scripts/Inventory.cs:39)
Inventory.Start () (at Assets/Scripts/Inventory.cs:32)

我犯了什么错误？

KeyNotFoundException和NullReferenceException

0 个答案: