为什么在我为它编写代码时，Crystal Report提示我输入参数字段值

Question

为什么在我为它编写代码时，Crystal报表提示我输入参数字段值。

Private void ReportVeiwer_Load(object sender, EventArgs e)
{
    ReportDocument reportdoc = new ReportDocument();
    ///string invoice_number = (;
    Invoice invoicerpt = new Invoice();

    ParameterField paramfield = new ParameterField();
    ParameterFields paramfields = new ParameterFields();
    paramfield.Name = "Invoice_Number";
    ParameterDiscreteValue dicval = new ParameterDiscreteValue();
    dicval.Value = User_Info.invoice_number;
    paramfield.CurrentValues.Add(dicval);
    paramfields.Add(paramfield);

    ReportVeiwer rptveiwer = new ReportVeiwer();
    rptveiwer.crystalReportViewer1.ParameterFieldInfo = paramfields;

    reportdoc.Load(@"D:\Furqan\SchoolManagementSystem\SchoolManagementSystem\Invoice.rpt");
    crystalReportViewer1.ReportSource = reportdoc;
    reportdoc.SetDatabaseLogon("PC-Name/User", "Password", ".", "Database");
}

Answer 1

首先加载报告。然后，设置参数值...