遍历Transform的子级时出错

Question

I want to loop over all children of a transform but I am getting an error.

This is the variable I want to get all the children from:

public Transform parentToSearch;

Then I dragged in the editor a Transform object from the Hierarchy to the script into parentToSearch .

Then later in the script I want to loop over all childs of this Transform:

private void OnGUI()
    {
        if (hasDescription == true && clickForDescription == true)
        {
            foreach (GameObject child in parentToSearch)
            {
                if (child.GetComponent<ItemInformation>() != null)
                {
                    ItemInformation iteminformation = child.GetComponent<ItemInformation>();
                    if (child.name == objectHit)
                    {
                        var centeredStyle = GUI.skin.GetStyle("Label");
                        centeredStyle.alignment = TextAnchor.UpperCenter;
                        GUI.Label(new Rect(Screen.width / 2 - 50, Screen.height / 2 - 25, 100, 50), iteminformation.description, centeredStyle);
                    }
                }
            }
        }
    }

The exception is on the line:

foreach (GameObject child in parentToSearch)

This is the error:

InvalidCastException: Cannot cast from source type to destination type

Answer 1

The parentToSearch variable is a type of Transform since it is declared as public Transform parentToSearch; . It's also an enumerator and when you use it in a foreach loop, you are accessing each child item in the array one by one. You must access it as a Transform not as a GameObject .

Change

foreach (GameObject child in parentToSearch)

to

foreach (Transform child in parentToSearch)