ParameterFields of ParameterFieldDefinitions for Crystal Report.NET parameters?

[my_lou]

ok, i have the following situation:

 

Crystal Report .NET untyped report with ReportDocument using strongly typed ADO.NET dataset for data access. I am opening the report in a Windows Form CrystalReportViewer. I want to pass parameters to it at runtime, but i can't figure out should i use the ParameterFieldInfo property of the CrystalReportViewer (in which case i'd have to use ParameterFields) or the DataDefintion.ParameterFields property of the ReportDocument class (in which case i'd have to use ParameterFieldDefinitions). To illustrate my point, here is some code. I use the following to pass parameters to Crystal Report using regular database, i.e. not DataSet, for data access and it works fine:

 

Imports System

Imports System.Collections

Imports System.Collections.Specialized

Imports CrystalDecisions.CrystalReports.Engine

Imports CrystalDecisions.Shared

 

Friend WithEvents Generic_CrystalReportViewer As CrystalDecisions.Windows.Forms.CrystalReportViewer

Friend WithEvents GenericComponent_reportDocument As CrystalDecisions.CrystalReports.Engine.ReportDocument

<System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()

Me.Generic_CrystalReportViewer = New CrystalDecisions.Windows.Forms.CrystalReportViewer

Me.GenericComponent_reportDocument = New CrystalDecisions.CrystalReports.Engine.ReportDocument

 

....

End Sub

 

 

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

 

_FileName = "myReport.rpt"

 

Me.GenericComponent_reportDocument.Load(_FileName)

 

 

Call Me.InitializeLogonCredentials()

 

Call Me.SetParameters()

 

Me.Generic_CrystalReportViewer.ParameterFieldInfo = crParamFields

 

 

Me.Generic_CrystalReportViewer.ReportSource = Me.GenericComponent_reportDocument

End Sub

 

Private Sub SetParameters()

'CrystalReports report's parameter fields to the viewer control.

Dim crParamField As New ParameterField

Dim crDiscreteVal As New ParameterDiscreteValue

 

crParamField.ParameterFieldName = CRREPORT_PARAMETER_SUFFIX & crParamName

 

crDiscreteVal.Value = DirectCast(Me.crParameters(crParamName), Integer)

 

 

'Pass discrete value to parameter.

crParamField.CurrentValues.Add(crDiscreteVal)

 

'Next add parameter to parameter fields collection.

crParamFields.Add(crParamField)

 

End Sub

 

However, that same code does not work if my report uses DataSet for data access. I tried the following, without success:

 

(this code added to the sub GenericCRViewer_Load)

 

Dim reportData As New DataSet

 

FillDataTable(True, "STUDENTTYPEID", reportData)

 

Me.GenericComponent_reportDocument.SetDataSource(reportData)

 

crPrmFieldDefinitions = Me.GenericComponent_reportDocument.DataDefinition.ParameterFields

Call Me.SetParameters()

 

For pfCount As Integer = 0 To crParamFields.Count - 1

crPrmFieldDefinitions(crParamFields(pfCount).ParameterFieldName).ApplyCurrentValues(crParamFields(pfCount).CurrentValues)

Next 'End For

 

In other words, i tried to populate the ParameterFieldDefintions collection with the members of the ParameterFields collection, with no luck.

 

What's the difference between ParameterFields and ParameterFieldDefintions anyway and when should each one be used?

 

Thanks all.

[my_lou]

oops, never mind that, it was a dumb mistake as are 99.99% of all coding errors.

 

Since I am a nice person and I do not wish the anguish I went through upon anybody else, I'll clarify what the problem was. It was in the sub-routine SetParameters(). In it I had something like this:

 

Private Sub SetParameters()

Dim crDiscreteVal As New ParameterDiscreteValue

Dim crParamField As New ParameterField

 

................

................

 

For Each crParam As String In crReportParams

Dim crParamName As String

 

crParamName = ............. 'code to build name

If crParamName <> "" Then

'Set the name of the parameter field. It must match a

'parameter field in the report.

crParamField.ParameterFieldName = crParamName

 

'Set discrete value.

crDiscreteVal.Value = ............ 'set discrete value

 

'Pass discrete value to parameter.

crParamField.CurrentValues.Add(crDiscreteVal)

 

'Next add parameter to parameter fields collection.

crParamFields.Add(crParamField)

End If

Next

End Sub

 

Do you see the problem with this code?...Well, here it is after the first time the ParameterField crParamField is inseretd in the collection crParamFields, it is never initialized so for the rest of the execution of the loop i just kep overwritting crParamField, hence inserting the same value in crParamFields over and over again. Dumb, I know!

 

Anyway, here is how to make this work:

 

Private Sub SetParameters()

Dim crDiscreteVal As New ParameterDiscreteValue

Dim crParamField As New ParameterField

 

................

................

 

For Each crParam As String In crReportParams

 

'***********************************************

' NEW code here *

'***********************************************

'Initialize ParameterField and ParameterDiscreteValue variables to

'new instances of their respective classes so the values already

'inserted in the ParameterFields collection would not be overwritten.

crDiscreteVal = New ParameterDiscreteValue

crParamField = New ParameterField

'***********************************************

' NEW code here *

'***********************************************

 

Dim crParamName As String

 

crParamName = ............. 'code to build name

If crParamName <> "" Then

'Set the name of the parameter field. It must match a

'parameter field in the report.

crParamField.ParameterFieldName = crParamName

 

'Set discrete value.

crDiscreteVal.Value = ............ 'set discrete value

 

'Pass discrete value to parameter.

crParamField.CurrentValues.Add(crDiscreteVal)

 

'Next add parameter to parameter fields collection.

crParamFields.Add(crParamField)

End If

Next

End Sub

 

So that took care of it.