Public Class Parameter 

public class Parameter 

private void SectionReport1_ReportStart(object sender, System.EventArgs eArgs)
{
    this.Parameters[0].DefaultValue = "Germany";
    this.Parameters[0].Key = "country";
    this.Parameters[0].Prompt = "Country: ";
    this.Parameters[0].Tag = "some extra data";
    this.Parameters[0].Type = GrapeCity.ActiveReports.SectionReportModel.Parameter.DataType.String;
}

Private Sub SectionReport1_ReportStart(ByVal sender As Object, ByVal e As System.EventArgs) Handles MyBase.ReportStart
    Me.Parameters(0).DefaultValue = "Germany"
    Me.Parameters(0).Key = "country"
    Me.Parameters(0).Prompt = "Country: "
    Me.Parameters(0).Tag = "Some extra data"
    Me.Parameters(0).Type = GrapeCity.ActiveReports.SectionReportModel.Parameter.DataType.String
End Sub