图片导入导出数据库

 1         private Stream stream=new Stream();
 2         Bitmap bp=new Bitmap();
 3         /// <summary>
 4         /// 向数据库中导入图片
 5         /// </summary>
 6         /// <param name="sender"></param>
 7         /// <param name="e"></param>
 8         private void button1_Click(object sender, EventArgs e)
 9         {
10             OpenFileDialog of = new OpenFileDialog();
11             if (of.ShowDialog() == DialogResult.OK)
12             {
13                 bp = new Bitmap(of.FileName);
14                 stream=of.OpenFile();//2下面
15             }
16             string sql = "update h_doctor set xiangPian=?xiangpian where ID="+12;
17             using (MySqlConnection conn = new MySqlConnection(mysqlHelp.ConnectionString))
18             {
19                 MySqlCommand cmd = new MySqlCommand(sql, conn);
20                 byte[] bytes = new byte[stream.Length];
21                 stream.Read(bytes, 0, (int)stream.Length);
22                 cmd.Parameters.AddWithValue("?xiangpian", bytes);
23                 try
24                 {
25                     conn.Open();
26                     cmd.ExecuteNonQuery();
27                     pictureBox1.Image = bp;
28                 }
29                 catch (Exception e1)
30                 {
31                     MessageBox.Show("图片太大！图片支持20K以内");
32                 }
33                 finally
34                 {
35                     conn.Close();
36                 }
37                 
38             }
39 
40         }
41         /// <summary>
42         /// 图片导出
43         /// </summary>
44         /// <param name="sender"></param>
45         /// <param name="e"></param>
46         private void button2_Click(object sender, EventArgs e)
47         {
48             string sql = "select xiangpian from h_doctor where ID=" + 12;
49             using (MySqlConnection conn = new MySqlConnection(mysqlHelp.ConnectionString))
50             {
51                 MySqlCommand cmd = new MySqlCommand(sql, conn);
52                 conn.Open();
53                 MySqlDataReader read = cmd.ExecuteReader();
54                 if (read.Read())
55                 {
56                     if (read[0].GetType() != typeof(DBNull))
57                     {
58                         byte[] bs = (byte[])read[0];
59                         MemoryStream mem = new MemoryStream(bs);
60                         Bitmap bm = new Bitmap(mem);
61                         pictureBox1.Image = bm;
62                     }
63                 }
64             }
65         }

2、 FileStream fs = File.OpenRead(of.FileName));
            byte[] imageb = new byte[fs.Length];
            fs.Read(imageb, 0, imageb.Length);
            fs.Close();
            SqlCommand com3 = new SqlCommand (sql,con);
            com3.Parameters.Add("@images", SqlDbType.Image).Value = imageb;