Is there an easy way to apply the same tag to all children of an object?

Questions & Answers
1

Basically this:

gameObject.tag = "theTag";

On a prefab, needs to tag all the children in the prefab with that tag, without knowing their names specifically.

Is it possible?

5

I made a small editor script, which will add an entry to the gameobject dropdown menu:
using UnityEngine;
using UnityEditor;
using System.Collections;

public class ChangeChildTags : MonoBehaviour {

    [MenuItem("GameObject/Change Children to Parent Tag")]
    public static void ChangeChildrenTags()
    {
        GameObject currentObject = Selection.activeGameObject;
        string parentTag = currentObject.tag;
        if (currentObject != null && currentObject.transform.childCount > 0)
        {
            if(EditorUtility.DisplayDialog("Change child tags to parent tag", "Do you really want to change every child tag to " + parentTag + "?", "Change tags", "Cancel"))
            {
                Transform[] transforms = Selection.GetTransforms(SelectionMode.Deep | SelectionMode.Editable);
                float numberOfTransforms = transforms.Length;
                float counter = 0.0f;
                foreach (Transform childTransform in transforms)
                {
                    counter ++;
                    EditorUtility.DisplayProgressBar("Changing tags", "Changing all child object tags to " + parentTag +
                        "

(" + (int)counter + “/” +(int)numberOfTransforms + “)”,
counter/numberOfTransforms);
childTransform.gameObject.tag = parentTag;
}
EditorUtility.ClearProgressBar();
}

        }
    }
}

Just create a class ChangeChildTags in the Editor folder. To change the children, select a gameobject and change the tag there. Then click on GameObject → Change Children to Parent Tag and the script will do the rest :slight_smile:

2

Not tested, but this should work (C#):

foreach(Transform t in transform)
{
    t.gameObject.tag = "theTag";
}
gameObject.tag = "theTag";
3

Thanks for this, I’ll check if it works. My initial feeling is that you can’t access grandchildren with GetComponents, because Unity throws an error as tags are not components…?

4

You can easily achieve that with a recursive method:

    AddTagRecursively (transform, "theTag");

void AddTagRecursively(Transform trans, string tag)
{
	trans.gameObject.tag = tag;
	if(trans.GetChildCount() > 0)
		foreach(Transform t in trans)
			AddTagRecursively(t, tag);
}