trail-into-darkness/Packages/com.jovian.utilities/Runtime/GameObjectUtilities.cs

using System;
using UnityEngine;
using Object = UnityEngine.Object;

namespace Jovian.Utilities {
    public static class GameObjectUtilities {
        public static void DestroyGameObjectsOfType<T>() where T : MonoBehaviour {
            var objects = Object.FindObjectsByType<T>(FindObjectsInactive.Include, FindObjectsSortMode.None);
            foreach(var t in objects) {
                Object.Destroy(t.gameObject);
            }
        }

        public static bool IsGameObjectAChildOfGameObject(this GameObject targetGameObject, GameObject potentialParentGameObject) {
            if(!targetGameObject) {
                return false;
            }

            var potentialParentTransform = potentialParentGameObject.transform;
            var checkTransform = targetGameObject.transform;
            do {
                if(checkTransform == potentialParentTransform) {
                    return true;
                }

                checkTransform = checkTransform.parent;
            } while(checkTransform);

            return false;
        }

        public static bool TryFindChildByName(this GameObject gameObject,
            string name,
            out GameObject childGameObject,
            bool includeInactive = false,
            bool allowPartialMatch = false,
            StringComparison stringComparison = StringComparison.Ordinal) {
            childGameObject = null;
            if(!gameObject) {
                return false;
            }

            var children = gameObject.GetComponentsInChildren<Transform>(includeInactive);
            foreach(var child in children) {
                if(allowPartialMatch && child.name.Contains(name, stringComparison)) {
                    childGameObject = child.gameObject;
                    return true;
                }

                if(!allowPartialMatch && child.name.Equals(name, stringComparison)) {
                    childGameObject = child.gameObject;
                    return true;
                }
            }

            return false;
        }
    }
}