将图像存储到数据库Blob；从数据库检索到Picturebox?mysql

您好，我在较早之前发布了此内容，并获得了一些帮助，但仍然没有有效的解决方案。由于最后的问与答，我确定我的“保存到数据库”代码以及“检索到图片”代码有问题。即使我手动将图片保存在数据库中，它也不会恢复。这是我从网络上的3或4个示例中修补而成的代码。理想情况下，如果有人拥有一些已知的良好代码，并且可以指导我这样做，那将是最好的。

Dim filename As String = txtName.Text + ".jpg"
Dim FileSize As UInt32
Dim ImageStream As System.IO.MemoryStream

ImageStream = New System.IO.MemoryStream
PbPicture.Image.Save(ImageStream, System.Drawing.Imaging.ImageFormat.Jpeg)
ReDim rawdata(CInt(ImageStream.Length - 1))
ImageStream.Position = 0
ImageStream.Read(rawdata, 0, CInt(ImageStream.Length))
FileSize = ImageStream.Length

Dim query As String = ("insert into actors (actor_pic, filename, filesize) VALUES    (?File, ?FileName, ?FileSize)")
cmd = New MySqlCommand(query, conn)
cmd.Parameters.AddWithValue("?FileName", filename)
cmd.Parameters.AddWithValue("?FileSize", FileSize)
cmd.Parameters.AddWithValue("?File", rawData)

cmd.ExecuteNonQuery()

MessageBox.Show("File Inserted into database successfully!", _
"Success!", MessageBoxButtons.OK, MessageBoxIcon.Asterisk)

！[在此处输入图片描述] [1]

'*****使用以下代码检索到图片框：

Private Sub GetPicture() 'This retrieves the pictures from a mysql DB and buffers the rawdata into a memorystream

Dim FileSize As UInt32
Dim rawData() As Byte

Dim conn As New MySqlConnection(connStr)


conn.Open()
conn.ChangeDatabase("psdb")


Dim cmd As New MySqlCommand("SELECT actor_pic, filesize, filename FROM actors WHERE actor_name = ?autoid", conn)
Cmd.Parameters.AddWithValue("?autoid", Actor1Box.Text)

Reader = cmd.ExecuteReader
Reader.Read()

'data is in memory 

FileSize = Reader.GetUInt32(Reader.GetOrdinal("filesize"))
rawData = New Byte(FileSize) {}

'get the bytes and filesize 

Reader.GetBytes(Reader.GetOrdinal("actor_pic"), 0, rawData, 0, FileSize)

Dim ad As New System.IO.MemoryStream(100000)
' Dim bm As New Bitmap

ad.Write(rawData, 0, FileSize)

Dim im As Image = Image.FromStream(ad) * "error occurs here" (see below)
Actor1Pic.Image = im


Reader.Close()


conn.Close()
conn.Dispose()

ad.Dispose()