Multivalue parm: displaymember values as report content

[Raoul]

I would like to add te selected values of a multivalued parm to the header of my report. E.g. I have a drop down with doctors loaded with a sql data source where doctorid (Guid) is the value member, and name (string) the display member. In my report I want to show the selected doctors or all available in case of no selection. I do not want to show the guids (obviously) but the names...
Yet, only the value members are accessible,  where I would like the get my hands on the display members.

This is my (working) code:

Public Shared Function VoorschrijverLabels(ByVal selection As Object(), ByVal reportItem As Object) As String

        Dim labels As String = String.Empty

        Try
            Dim processingReport As Telerik.Reporting.Processing.Report = TryCast(reportItem, Telerik.Reporting.Processing.ReportItemBase).Report
            Dim report As rptDagstaat = TryCast(processingReport.ItemDefinition, rptDagstaat)
            Dim da As New SqlDataAdapter(report.dsVoorschrijvers.SelectCommand, report.dsVoorschrijvers.ConnectionString)
            Dim ds As New DataSet
            da.Fill(ds)

            For Each row As DataRow In ds.Tables(0).Rows
                If labels.Length > 0 Then labels += "; "
                If selection Is Nothing OrElse selection.Contains(row("VoorschrijverID").ToString) Then
                    labels += row("Voorschrijver")
                End If
            Next

        Catch ex As Exception
        End Try

        Return labels

    End Function

Basically I do an extra query to the database to get the paramater datasource values (again!), and compare them against the selected  value members.
But as you can see, it is not very generic... It's per parameter because I need to cast the report to access the parameter data source and the specific parameter data source properties. A separate function for each multivalued parameter with a separate database call...

The selection variable contains an ArrayList(Of string) These are casted value members of the parameter data source {CStr(VoorschrijverID)} The result of this function is a string with the names of the doctors semicolon separated.

My question is: Is there a more easy way to do this? Preferably without the database call and accessing the parameter data source directly.

Regards,
Raoul

[Peter]

Hi Raoul,

You can directly access the selected report parameter display member with the following expression:
=Parameters.ReportYear.Label
However if you utilize multi value report parameter you will have to format the resulting string array in the required string format. For this you can use an user function as shown in the following example:

Public Shared Function FormatArray(ByVal array As IList) As String
    Dim sb As New StringBuilder()

    For Each o As Object In array
        If sb.Length > 0 Then
            sb.Append("; ")
        End If
        sb.Append(o.ToString())
    Next

    Return sb.ToString()
End Function

Greetings,
Peter
the Telerik team