Trouble in converting an image from database to byte and back to image - vb.net

Question

I have a button and a datagridview in my form. I need to get the image from the database and display its value in the datagrid then get the value of the image in the datagrid to copy it to another database.
Specifically, I'm copying the image (blob) from table1 of database1 to table 1 of database2.
Button1_click:
Dim img As Image
Dim bArr As Byte()
Try
Dim Sql = "Select ID, IMG from sample"
connectionOnline()
Dim cmd = New MySqlCommand(Sql, ConOnline)
Dim dr = cmd.ExecuteReader(CommandBehavior.CloseConnection)
DataGridView1.Rows.Clear()
While dr.Read = True
img = dr(1)
bArr = imgToByteArray(img)
DataGridView1.Rows.Add(dr(0), bArr)
End While
ConOnline.Close()
Catch ex As Exception
MsgBox(ex.Message)
End Try
Try
connectionSync()
Dim a, b As String
Dim Sql = "INSERT INTO SAMPLE (ID, IMG)values(#a,#b)"
For i As Integer = 0 To Me.DataGridView1.Rows.Count - 1
a = Me.DataGridView1.Rows(i).Cells(0).Value.ToString()
Dim img1 As Image = byteArrayToImage(bArr)
Dim cmd As New MySqlCommand(Sql, ConSync)
cmd.Parameters.AddWithValue("#a", a)
cmd.Parameters.AddWithValue("#b", img1)
cmd.ExecuteNonQuery()
cmd.Parameters.Clear()
Next
ConSync.Close()
Catch ex As Exception
MsgBox(ex.Message)
End Try
Try
connectionSync()
Dim Sql = "INSERT INTO B.SAMPLE(ID, IMG) SELECT ID, IMG FROM C.SAMPLE WHERE not exists (SELECT 1 from B.SAMPLE WHERE B.SAMPLE.ID=C.SAMPLE.ID)"
Dim cmd = New MySqlCommand(Sql, ConSync)
With cmd
.ExecuteNonQuery()
End With
MsgBox("Success", vbInformation, "Save")
ConSync.Close()
Catch ex As Exception
MsgBox(ex.Message)
End Try
Try
connectionOffline()
Dim Sql = "UPDATE SAMPLE SET IMG=(SELECT C.SAMPLE.NAME FROM C.SAMPLE WHERE C.SAMPLE.ID=B.SAMPLE.ID) WHERE B.SAMPLE.ID=(SELECT C.SAMPLE.ID FROM C.SAMPLE WHERE C.SAMPLE.ID=B.SAMPLE.ID)"
Dim cmd = New MySqlCommand(Sql, ConOffline)
With cmd
.ExecuteNonQuery()
End With
MsgBox("Success")
ConOffline.Close()
Catch ex As Exception
MsgBox(ex.Message)
End Try
B and C are databases
While sample is the table
below are the functions i used to convert the image
Public Function imgToByteArray(ByVal img As Image) As Byte()
Using mStream As New MemoryStream()
img.Save(mStream, img.RawFormat)
Return mStream.ToArray()
End Using
End Function
Public Function byteArrayToImage(ByVal byteArrayIn As Byte()) As Image
Using mStream As New MemoryStream(byteArrayIn)
Return Image.FromStream(mStream)
End Using
End Function
The result (in the database; IMG) only shows: "System.Drawing.Bitmap" instead of the actual image

Answer 1

You are storing only a "Image.ToString".
Try to use a Binary parameter:
Dim yourParam As new SqlParameter("#b", System.Data.SqlDbType.Binary)
yourParam.Direction = ParameterDirection.Input
' yourParam.value= yourImage ' you can't place a system.drawin.image here
Dim ms As New MemoryStream()
yourImage.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg)
yourParam.value= ms.ToArray() ' similar to your imgToByteArray function ....
cmd.Parameters.Add(yourParam)