//存图片到DB
    private void button1_Click(object sender, EventArgs e)
    {
        Stream ms;
        byte[] picbyte;
        OpenFileDialog ofdSelectPic = new OpenFileDialog();
        ofdSelectPic.ShowDialog();
        string f = ofdSelectPic.FileName;

        ms = ofdSelectPic.OpenFile();
        picbyte = new byte[ms.Length];
        ms.Position = 0;
        ms.Read(picbyte, 0, Convert.ToInt32(ms.Length));

        SqlConnection conn = new SqlConnection("server=.;uid=sa;pwd=;database=s");
        conn.Open();
        string sqlstring = "insert into ttt(image) values(@img)";
        SqlCommand cmd = new SqlCommand(sqlstring, conn);
        cmd.Parameters.Add("@img", SqlDbType.Image, picbyte.Length).Value = picbyte;

        cmd.ExecuteNonQuery();
        conn.Close();
    }
    //由数据取图片

    private void button2_Click(object sender, EventArgs e)
    {
        SqlConnection conn = new SqlConnection("server=.;uid=sa;pwd=;database=s");
        conn.Open();
        string strSql = "select image from ttt ";
        SqlCommand cmd = new SqlCommand(strSql, conn);
        SqlDataReader sdr = cmd.ExecuteReader();
        sdr.Read();
        MemoryStream ms = new MemoryStream((byte[])sdr[0]);
        Image image = Image.FromStream(ms);
        sdr.Close();
        conn.Close();
        pictureBox1.Image = image;
    }