[MenuItem("Tools/testselect")]    public static void testselect()    {        UnityEngine.Object[] arr=Selection.GetFiltered(typeof(UnityEngine.Object), SelectionMode.TopLevel);        Debug.LogError(Application.dataPath.Substring(0,Application.dataPath.LastIndexOf('/'))+"/"+ AssetDatabase.GetAssetPath(arr[0]));    }

如果要遍历目录，修改为
SelectionMode.DeepAssets

这个方法只能对右边选中的文件生效，左边的无效