c#
static private string GET_File_MD5(string path)
{
    try
    {
        byte[] buffer = File.ReadAllBytes(path); ;
        System.Security.Cryptography.MD5 file1_md5 = MD5.Create();
        byte[] retval = file1_md5.ComputeHash(buffer);
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < retval.Length; i++)
        {
            sb.Append(retval[i].ToString("X2"));
        }
        return sb.ToString();
    }
    catch (Exception ep)
    {
        Console.WriteLine(ep.Message);
        return "";
    }
}