FileInfo info = new FileInfo(fileName)
string path = info.FullName;

string path = string.Empty;
string fileName = Path.GetFileName(path);

public bool ckIsFileOpnen(string sFileFullPath)
        {
            try
            {
                using (Stream stream = new FileStream(sFileFullPath, FileMode.Open, FileAccess.ReadWrite, FileShare.None))
                {
                }
                return true; //file is available for write
            }
            catch { }

            return false;
        }