C# 實現文本文件存入數據庫並取出

byte[]text= File.ReadAllBytes(this.openFileDialog1.FileName);
           SqlConnection con = new SqlConnection("data source=.;initial catalog=demo;user id=sa;pwd=");
           SqlCommand comm = new SqlCommand("Insert Into c (s) Values (@Image)", con);
           comm.Parameters.Add(new SqlParameter("@Image", text));
           con.Open();
           comm.ExecuteNonQuery();
           con.Close();
           string sql = "select s from c";
           comm = new SqlCommand(sql, con);
           con.Open();
           byte[] s = (byte[])comm.ExecuteScalar();
           this.textBox1.Text = System.Text.Encoding.Default.GetString(s, 0, s.Length);