UnityEditor.PresetLibraryLocations.GetFilesWithExentionFromFolders C# (CSharp) Method

        private static List<string> GetFilesWithExentionFromFolders(List<string> folderPaths, string fileExtensionWithoutDot)
        {
            List<string> list = new List<string>();
            foreach (string str in folderPaths)
            {
                string[] files = Directory.GetFiles(str, "*." + fileExtensionWithoutDot);
                list.AddRange(files);
            }
            return list;
        }

        public static List <string> GetAvailableFilesWithExtensionOnTheHDD(PresetFileLocation fileLocation, string fileExtensionWithoutDot)
        {
            List <string> exentionFromFolders = PresetLibraryLocations.GetFilesWithExentionFromFolders(PresetLibraryLocations.GetDirectoryPaths(fileLocation), fileExtensionWithoutDot);

            for (int index = 0; index < exentionFromFolders.Count; ++index)
            {
                exentionFromFolders[index] = PresetLibraryLocations.ConvertToUnitySeperators(exentionFromFolders[index]);
            }
            return(exentionFromFolders);
        }