public bool CanMergeFile(string pathToFile)
{
if (string.IsNullOrEmpty(pathToFile))
return false;
if (!File.Exists(pathToFile))
return false;
var extension = Path.GetExtension(pathToFile);
if (string.IsNullOrEmpty(extension))
return false;
if (extension[0] != '.')
return false;
return FileUtils.CheckValidPathname(pathToFile, ".htm") || FileUtils.CheckValidPathname(pathToFile, ".html");
}