C#實現MySQL數據庫中的blob數據存儲

1 System.IO.MemoryStream ms = new System.IO.MemoryStream();

  2 private void button1_Click(object sender, EventArgs e)

  3 {

  4 //測試序列化與反序列化

  5 int [] arr = { 1 , 2 , 3 };

  6 BinaryFormatter bFormatter = new BinaryFormatter();

  7 bFormatter.Serialize(ms, arr);

  8 byte [] byteArr = ms.ToArray();

  9 MessageBox.Show(byteArr.Length.ToString());

10 MySqlConnection conn = new MySqlConnection(Properties.Settings.Default.MySqlConnectString);

11 //string insertStr = "update mm set aa=4,arr=@blobData where aa=4;";

12 string insertStr = "insert into mm(arr) values(@blobData);" ; //須要主鍵設置自增

13 MySqlParameter par= new MySqlParameter( "@blobData" ,MySqlDbType.Blob);

14 par.Value=byteArr;

15 MySqlCommand cmd = new MySqlCommand(insertStr, conn);

16 cmd.Parameters.Add(par);

17 try

18 {

19 conn.Open();

20 cmd.ExecuteNonQuery();

21 ms.Close();

22 ms.Dispose();

23 }

24 catch (Exception ep)

25 {

26 MessageBox.Show(ep.Message);

27 }

28

29

30 }

31

32 private void button2_Click(object sender, EventArgs e)

33 {

34 BinaryFormatter bFormatter = new BinaryFormatter();

35

36 MySql.Data.MySqlClient.MySqlDataReader myData;

37 MySqlConnection  conn = new MySql.Data.MySqlClient.MySqlConnection(Properties.Settings.Default.MySqlConnectString);

38 string readStr = "select arr from mm where id =6;" ;

39 MySqlCommand cmd = new MySqlCommand(readStr, conn);

40 try

41 {

42 conn.Open();

43 myData = cmd.ExecuteReader();

44 if (!myData.HasRows)

45 {

46 throw new Exception( "沒有blob數據" );

47 }

48 myData.Read();

49 byte [] blob = new byte [myData.GetBytes( 0 , 0 , null , 0 , int .MaxValue)];

50 myData.GetBytes( 0 , 0 , blob, 0 , blob.Length);

51 myData.Close();

52 ms = new System.IO.MemoryStream(blob);

53 ms.Position = 0 ;

54 int [] arr = ( int [])bFormatter.Deserialize(ms);

55 ms.Dispose();

56 string arrStr = null ;

57 for ( int i = 0 ; i < arr.GetLength( 0 ); i++)

58 {

59 arrStr += arr[i].ToString()+ " " ;

60 }

61 MessageBox.Show(arrStr);

62 }

63 catch (Exception ep)

64 {

65 MessageBox.Show(ep.Message);

66 }

67

68 }