string connectionString = @"";
        
        OleDbConnection connection = new OleDbConnection(connectionString);

        string MyString;

        MyString = "insert into tabAllegatiCommessa (ContenutoFile) values(@Prova)";
        
        string path = @"C:\Prova.JPG";


        FileStream fs = new FileStream(path, FileMode.Open, FileAccess.Read);

        BinaryReader br = new BinaryReader(fs);

        FileInfo fi = new FileInfo(path);

        byte[] imagedata = br.ReadBytes((int)fi.Length);


        try
        {
  

            OleDbCommand InsertImage = new OleDbCommand(MyString, connection);
            connection.Open();



            InsertImage.Parameters.Add("@Prova", OleDbType.Binary);
            InsertImage.Parameters["@Prova"].Value = imagedata;
            InsertImage.Parameters.AddWithValue("@Prova", imagedata);

      

            InsertImage.ExecuteNonQuery();

            connection.Close();
        }
        catch (Exception ex)
        {
            Response.Write(ex.Message);
        }