How to: Access the Report Parameters Object in Calculated Fields Expressions

• Jun 11, 2019
• 2 minutes to read

This topic describes how you can access data of a report parameters object (inherited from ReportParametersObjectBase and specified using IReportDataV2.ParametersObjectType) in calculated field expressions.

Note

The approach described in this topic is not supported by the Mobile platform.

Override the Parameters Object’s ToString method.

C#

public class DemoParameters : ReportParametersObjectBase {
    // ...
    public override string ToString() {
        return City;
    }
}

VB.NET

Public Class DemoParameters
    Inherits ReportParametersObjectBase
    ' ...
    Public Overrides Function ToString() As String
        Return City
    End Function
End Class

As a result, you can refer to the ToString result with the “[Parameters.XafReportParametersObject]” expression, e.g.:

Concat([Full Name],' from ', [Parameters.XafReportParametersObject])

Alternatively, you can create a report script, handle the GetValue event of a certain field and then access a parameter value as demonstrated in the How to: Access the Report Parameters Object in Report Scripts topic.

C#

private void calculatedFieldCity_GetValue(object sender, DevExpress.XtraReports.UI.GetValueEventArgs e) {
    DevExpress.XtraReports.Parameters.Parameter param =
            (DevExpress.XtraReports.Parameters.Parameter)
                ((DevExpress.XtraReports.UI.XtraReport)e.Report).Parameters["XafReportParametersObject"];
    if (param != null) {
        ReportV2Demo.Module.BusinessObjects.Contact contact = 
        (ReportV2Demo.Module.BusinessObjects.Contact)e.Row;
        ReportV2Demo.Module.Reports.DemoParameters xafParameter =
            (ReportV2Demo.Module.Reports.DemoParameters)param.Value;
        e.Value = contact.FullName + " from " + xafParameter.City;
    }
}

VB.NET

Private Sub calculatedFieldCity_GetValue(ByVal sender As Object, ByVal e As DevExpress.XtraReports.UI.GetValueEventArgs)
    Dim param As DevExpress.XtraReports.Parameters.Parameter = _
    CType(((DevExpress.XtraReports.UI.XtraReport)e.Report).Parameters("XafReportParametersObject"), _
    DevExpress.XtraReports.Parameters.Parameter)
    If param IsNot Nothing Then
        Dim contact As ReportV2Demo.Module.BusinessObjects.Contact = _
        CType(e.Row, ReportV2Demo.Module.BusinessObjects.Contact)
        Dim xafParameter As ReportV2Demo.Module.Reports.DemoParameters = _
        CType(param.Value, ReportV2Demo.Module.Reports.DemoParameters)
        e.Value = contact.FullName & " from " & xafParameter.City
    End If
End Sub