Extracting a database binary to an RDLC Image field

Question

Continuing my research into implementing RDLC reports.  One functionality we require is displaying inventory
images on the report. This will be a VB.net 2005 app running on workstations. A simplified environment has been
staged by adding and populating an image field in The Northwind Customers table. An extraction function 
was tested successfully on a winform app populating a picturebox.  My sticking point is that there is not an
"Expression" context menu for an image control.  The "Data Region" combobox doesn’t seem right.
The function references only Row 2 for now, because I'm not used to working with bound controls
and don't know how to reference the current record. Any help is much appreciated !

Found this so far: http://msdn.microsoft.com/en-us/library/ms251715(VS.80).aspx

http://i286.photobucket.com/albums/ll84/gto866/Dev/RDLC2.jpg

Imports Microsoft.Reporting.WinForms
Imports System.IO
Public Class Form1

Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

Me.CustomersTableAdapter.Fill(Me.northwndDataSet.Customers)
Me.ReportViewer1.LocalReport.EnableExternalImages = True
Me.ReportViewer1.RefreshReport()
End Sub

Private Function ByteToImage() As Image

Dim objImage As Image
Dim bytImageBuffer() As Byte
Dim objMemoryStream As MemoryStream

bytImageBuffer = Me.northwndDataSet.Tables(0).Rows(2).Item("ImagePicture")
objMemoryStream = New MemoryStream(bytImageBuffer, True)
objMemoryStream.Write(bytImageBuffer, 0, bytImageBuffer.Length)
objImage = Image.FromStream(objMemoryStream)
ByteToImage = objImage
End Function
End Class

Update:

After reading about the CODE global variable, I tried this:
Go to the Report->Properties menu
Click the Code tab and define the function.
Click the Element tab. enter      Image1
Click the Data Output tab and enter      =Code.ByteToImage(Fields!ImagePicture.value))

This is possibly moving in the right direction, but still errors out with
"Value expression for image1 is an empty string"

http://i286.photobucket.com/albums/ll84/gto866/Dev/RDLC3.jpg


Update:
To eliminate dataset problems, replaced expression with a simple function to
return a bitmap from file. Still errors out with the empty string message

Answer 1

Have you tried just binding to the byte array instead of the Image?

Answer 2

It worked !

http://i286.photobucket.com/albums/ll84/gto866/RDLC4.jpg

A couple of my searches showed somewhat similar requests and the response was a write a custom expression.
So  .Net handles this natively. Very nice.


Thanks,
Steve 

 

 

 

PS.

Actually it was on MSDN where I saw this
http://msdn.microsoft.com/en-us/library/ms251715.aspx

Using an External or Database Image to a Report

To use a database image, you can specify the database field that contains the image as long as the MIME type is JPG, PNG, or BMP. If the image is stored as a binary object, you must write an expression that converts the image to a supported type.

 

Answer 3

Uhh...and the custom expression was??

Answer 4

There's no need for the custom expression. Just binding the byte array works.