Save binary file from SQL Server - vb.net

Question

I'm trying to save a binary file stored in a SQL database with a SaveDialog, the function RetrieveFile retrieves the specified file from the database as a Byte array, here's what I have so far:
Private Shared Function RetrieveFile(ByVal filename As String) As Byte()
Dim connection As New SqlConnection("Data Source=SERVER\SQL2008;Initial Catalog=NorthPole;Integrated Security=True")
Dim command As New SqlCommand("SELECT pcfFile FROM Items WHERE pcfFileName=#Filename", connection)
command.Parameters.AddWithValue("#Filename", filename)
connection.Open()
Dim reader As SqlDataReader = command.ExecuteReader(System.Data.CommandBehavior.SequentialAccess)
reader.Read()
Dim memory As New MemoryStream()
Dim startIndex As Long = 0
Const ChunkSize As Integer = 256
While True
Dim buffer As Byte() = New Byte(ChunkSize - 1) {}
Dim retrievedBytes As Long = reader.GetBytes(1, startIndex, buffer, 0, ChunkSize)
memory.Write(buffer, 0, CInt(retrievedBytes))
startIndex += retrievedBytes
If retrievedBytes <> ChunkSize Then
Exit While
End If
End While
connection.Close()
Dim data As Byte() = memory.ToArray()
memory.Dispose()
Return data
End Function
Private Sub SaveAsToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles SaveAsToolStripMenuItem.Click
Dim saveFileDialog1 As New SaveFileDialog()
saveFileDialog1.Filter = "PCF File|*.pcf|"
saveFileDialog1.Title = "Save an pcf File"
saveFileDialog1.ShowDialog()
If saveFileDialog1.FileName <> "" Then
Dim fs As System.IO.FileStream = CType(RetrieveFile("FakePCF.pcf"), System.IO.FileStream)
fs.Close()
End If
End Sub
Files are saved as "SqlDbType.VarBinary" within the database.
I get: "Index was outside the bounds of the array." on:
Dim retrievedBytes As Long = reader.GetBytes(1, startIndex, buffer, 0, ChunkSize)
The MemoryStream appears to not be retrieving the data yet the SQL sytax is correct.
What am I doing wrong?

Answer 1

Well, first of all, your method returns byte[] and you're trying to cast it to FileStream. You should change your handler to following:
Private Sub SaveAsToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles SaveAsToolStripMenuItem.Click
Dim saveFileDialog1 As New SaveFileDialog()
saveFileDialog1.Filter = "PCF File|*.pcf|"
saveFileDialog1.Title = "Save an pcf File"
saveFileDialog1.ShowDialog()
If saveFileDialog1.FileName <> "" Then
Dim fs As New System.IO.FileStream (saveFileDialog1.FileName, System.IO.FileMode.Create, System.IO.FileAccess.Write)
Dim data As Byte() = RetrieveFile("FakePCF.pcf")
fs.Write(data, 0, data.Length)
fs.Flush()
fs.Close()
End If
End Sub