Storing multiple images in SQL Database
I'm trying to store three images from a form (PictureBox's) into a SQL Database (MSSQL2008) I'm new to programming and having a little difficulty simplifying my code. The below does what I want but is clearly inefficient. Any pointers on what to change to improve this?
Private Sub SaveImages()
Dim ConStr As String = "Data Source=SERVER\SQL2008;Initial Catalog=NorthPole;Integrated Sec开发者_StackOverflow中文版urity=True"
Dim con As New SqlConnection(ConStr)
Dim sqlCommand As New SqlCommand()
sqlCommand.Connection = con
sqlCommand.CommandText = "INSERT INTO Items (ItemID, ItemNumber, ItemImage1, ItemImage2, ItemImage3) SELECT NEWID(), @ItemNumber, @ItemImage1, @ItemImage2, @ItemImage3"
sqlCommand.Parameters.Add(New SqlParameter("@ItemNumber", SqlDbType.VarChar, 20)).Value = "MS1006"
Dim ms1 As MemoryStream = New MemoryStream()
PictureEdit1.Image.Save(ms1, System.Drawing.Imaging.ImageFormat.Jpeg)
sqlCommand.Parameters.Add(New SqlParameter("@ItemImage1", SqlDbType.VarBinary)).Value = ms1.GetBuffer
Dim ms2 As MemoryStream = New MemoryStream()
PictureEdit2.Image.Save(ms2, System.Drawing.Imaging.ImageFormat.Jpeg)
sqlCommand.Parameters.Add(New SqlParameter("@ItemImage2", SqlDbType.VarBinary)).Value = ms2.GetBuffer
Dim ms3 As MemoryStream = New MemoryStream()
PictureEdit3.Image.Save(ms3, System.Drawing.Imaging.ImageFormat.Jpeg)
sqlCommand.Parameters.Add(New SqlParameter("@ItemImage3", SqlDbType.VarBinary)).Value = ms3.GetBuffer
con.Open()
sqlCommand.ExecuteNonQuery()
con.Close()
End Sub
Private Sub LoadImages()
Dim ConStr As String = "Data Source=SERVER\SQL2008;Initial Catalog=NorthPole;Integrated Security=True"
Dim con As New SqlConnection(ConStr)
con.Open()
Dim sqlCommand As New SqlCommand()
sqlCommand.Connection = con
sqlCommand.CommandText = "SELECT ItemImage1 FROM items WHERE ItemNumber = 'MS1006'"
Dim buffer1 As Byte() = sqlCommand.ExecuteScalar()
Dim ms1 As MemoryStream = New MemoryStream(buffer1)
PictureEdit1.Image = Image.FromStream(ms1)
sqlCommand.CommandText = "SELECT ItemImage2 FROM items WHERE ItemNumber = 'MS1006'"
Dim buffer2 As Byte() = sqlCommand.ExecuteScalar()
Dim ms2 As MemoryStream = New MemoryStream(buffer2)
PictureEdit2.Image = Image.FromStream(ms2)
sqlCommand.CommandText = "SELECT ItemImage3 FROM items WHERE ItemNumber = 'MS1006'"
Dim buffer3 As Byte() = sqlCommand.ExecuteScalar()
Dim ms3 As MemoryStream = New MemoryStream(buffer3)
PictureEdit3.Image = Image.FromStream(ms3)
con.Close()
End Sub
One simple step to cut down the duplication - have a function to get you the bytes for your jpgs...
Private Function GetJpegBytesForImage(theImage As Image) As Byte()
Using ms As MemoryStream = New MemoryStream()
theImage.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg)
Return ms.GetBuffer()
End Using
End Function
...similarly for the reverse...
Private Function GetImageForJpegBytes(theBytes As Byte()) As Image
Using ms As MemoryStream = New MemoryStream(theBytes)
return Image.FromStream(ms)
End Using
End Function
Note that when loading the images, you don't need three separate queries - you can perform one query that brings back the three columns and then extract each of the images from the relevant column.
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