UnityEngine.SceneManagement.SceneUtility.GetScenePathByBuildIndex C# (CSharp) Method

        public static extern string GetScenePathByBuildIndex(int buildIndex);
    }

    void Start()
    {
        this.curIdx  = 1;
        this.lastIdx = -1;

        for (int i = SceneMng.sceneCountInBuildSettings; i > 0; i--)
        {
            string name = SceneUtil.GetScenePathByBuildIndex(i - 1);
            if (name.IndexOf(this.StopLoadingAt) != -1)
            {
                this.lastIdx = i - 1;
                break;
            }
        }
        if (this.lastIdx == -1)
        {
            throw new System.Exception("Couldn't find the last level");
        }

        if (CreateLevelSelectors.cache == null)
        {
            cache = new CachedLevel[this.lastIdx];
            for (int i = 0; i < cache.Length; i++)
            {
                CreateLevelSelectors.cache[i].tex = null;
                CreateLevelSelectors.cache[i].mat = null;
            }
        }

        this.StartCoroutine(this.start());
    }