how to use parameter in crystal report

[imagetvr]

I Wish to pass parameter to Crystal Report. I have Access data base one table named student. I with to select range of data's from that table field named "rno"

i am using visual basic 6

I used following code to view crystal report
================================================
Set rs = New ADODB.Recordset
modConnection.opendb
rs.Open "select * from STUDENT_M order by rno", cn, adOpenStatic, adLockPessimistic
Report.Database.SetDataSource rs
Screen.MousePointer = vbHourglass
CRViewer1.ReportSource = Report
CRViewer1.ViewReport

Screen.MousePointer = vbDefault


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I am new to crystal report. please guide me how to use parameter in crystal report.


a.Senthil kumar.

[thered]

I don't use VB6 but I do something like this.

you can add as many parameters as are needed for the report.

        If dtFromDate <> Nothing And dtToDate <> Nothing Then
            strSelectField = "@dtFromDate=" & dtFromDate.ToString
            strSelectField &= "&@dtToDate=" & dtToDate.ToString
        End If

in your standard selection of the report

            If intCounter1 > 0 And Trim(param) <> "" Then
                strParValPair = param.Split("&")
                For index = 0 To UBound(strParValPair)
                    If InStr(strParValPair(index), "=") > 0 Then
                        strVal = strParValPair(index).Split("=")
                        paraValue.Value = strVal(1)
                        currValue = _
                         objReport.DataDefinition.ParameterFields(strVal(0)).CurrentValues
                        currValue.Add(paraValue)
                        objReport.DataDefinition.ParameterFields(strVal(0)).ApplyCurrentValues(currValue)
                    End If
                Next
            End If

Then I add Parameters @dtFromDate and @dtToDate in your report.

you can use them in the select expert

{MediaDetails.PurchaseDate} in {?@dtFromDate} to  {?@dtToDate}

[sigiK]

First, add a paramater to your report ...

Dim crRep As New CrystalDecisions.CrystalReports.Engine.ReportDocument
Dim crParHeader As New CrystalDecisions.Shared.ParameterDiscreteValue

crRep.Load(Application.StartupPath & "/Report/" & xReport & ".rpt")

crParHeader.Value = xReportname
crRep.ParameterFields("Header").CurrentValues.Add(crParHeader)

' Display or Print
If xOption = "Display" Then
CrystalReportViewer.ReportSource = crRep
Else
crRep.PrintToPrinter(1, True, 0, 0)
End If

[marco.c84]

First, add a paramater to your report ...

Dim crRep As New CrystalDecisions.CrystalReports.Engine.ReportDocument
Dim crParHeader As New CrystalDecisions.Shared.ParameterDiscreteValue

crRep.Load(Application.StartupPath & "/Report/" & xReport & ".rpt")

crParHeader.Value = xReportname
crRep.ParameterFields("Header").CurrentValues.Add(crParHeader)

' Display or Print
If xOption = "Display" Then
CrystalReportViewer.ReportSource = crRep
Else
crRep.PrintToPrinter(1, True, 0, 0)
End If

At:

crRep.ParameterFields("Header").CurrentValues.Add(crParHeader)

NullReferenceException exception is thrown.

[sigiK]

did you add a parameter "Header" to your report ?