Iterating through children causes InvalidCastException

Questions & Answers
1

Hello,
I want to make a dynamic shop UI, but when changing the category I want to, obviously, clear whatever was previously in it. So I am iterating through all children, which for some reason causes an InvalidCastException. I have used the same loop in a different part of my code, but there it doesn’t throw the exception.

Code:

public void LoadForCategory(BuildingCategory category)
    {
        foreach(GameObject child in this.transform) // This is line 12 where the error occurs.
        {
            Destroy(child);
        }

        List<Building> buildings = new List<Building>();

        if(category == BuildingCategory.DECORATION)
        {
            buildings = BuildingsRegistry.self.FilterByCategories(new BuildingCategory[] { BuildingCategory.DECORATION });
        }

        foreach(Building building in buildings)
        {
            GameObject newButton = Instantiate(buildingItemPrefab);
            newButton.transform.Find("PriceText").GetComponent<Text>().text = "$ " + building.price;
            newButton.transform.Find("PreviewImage").GetComponent<Image>().sprite = building.preview;
            newButton.transform.parent = transform;
        }
    }

The error:

InvalidCastException: Specified cast is not valid.
BuildingItemList.LoadForCategory (BuildingCategory category) (at Assets/Scripts/Mechanics/Building/UI/BuildingItemList.cs:12)
BuildingCategoryButton.OnClick () (at Assets/Scripts/Mechanics/Building/UI/BuildingCategoryButton.cs:12)
UnityEngine.Events.InvokableCall.Invoke () (at <f98083cbc97e4fa0a4ef2f523feff5e1>:0)
UnityEngine.Events.UnityEvent.Invoke () (at <f98083cbc97e4fa0a4ef2f523feff5e1>:0)
2

Update: I spotted my mistake by changing GameObject to dynamic and then doing GetType().Name, which turned out to be RectTransform and not GameObject.