Accessing Data from Rendered Report in WinForms Viewer

Environment

Product

Reporting

Description

I need to display a TRDP or TRDX report in the WinForms Report Viewer, click a button, and extract specific values (e.g., client email) from the rendered report. Essentially, I need access to the processed report or the report's data source fields from outside the report.

This knowledge base article also answers the following questions:

• How to get data from a rendered report in WinForms Report Viewer?
• How to use report parameters to retrieve values from a report?
• How to use report events to access processed report values?

Solution

Using Report Parameters

Use report parameters to retrieve values from the report. Connect the report parameter to the desired field of the data source component whose data you need to access.

1. Create a report parameter in the report designer, connect it to the needed data source component, and bind its Value and ValueMember properties to the required field. You may use the same expression for both properties - = Fields.MyField.
2. Access the report parameter value in the application code through the viewer's ReportSource property:

   Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
       Dim reportParameterValue = Me.ReportViewer1.ReportSource.Parameters("MyParameter").Value
   End Sub

private void Button1_Click(object sender, EventArgs e)
{
    var reportParameterValue = this.ReportViewer1.ReportSource.Parameters["MyParameter"].Value;
}

Using Report Events

For scenarios requiring multiple values from the processed report, use report events. For TRDP/TRDX files, they must be unpackaged/deserialized in order to assign custom event handlers to the reports.

        private void MainForm_Load(object sender, System.EventArgs e)
        {
            var uri = "C:\Path\To\Report.trdp";
            var reportPackager = new ReportPackager();
            var instanceReportSource = new InstanceReportSource();  

            using (var sourceStream = System.IO.File.OpenRead(uri))
            {
                var report = (Telerik.Reporting.Report)reportPackager.UnpackageDocument(sourceStream);

                // reading values from the detail section
                var table = report.Items.Find("table1", true)[0] as Telerik.Reporting.Table;
                table.ItemDataBound += Table_ItemDataBound;

                // reading values from a table
                var detailSection = report.Items.Find("detailSection1", true)[0] as Telerik.Reporting.DetailSection;
                report.ItemDataBound += Report_ItemDataBound;

                instanceReportSource.ReportDocument = report;
            }

            this.reportViewer1.ReportSource = instanceReportSource;
            this.reportViewer1.RefreshReport();
        }

Private Sub MainForm_Load(sender As Object, e As EventArgs) Handles MyBase.Load
       Dim uri As String = "C:\Path\To\Report.trdp"
       Dim reportPackager As New ReportPackager()
       Dim instanceReportSource As New InstanceReportSource()

       Using sourceStream As FileStream = File.OpenRead(uri)
           Dim report As Report = CType(reportPackager.UnpackageDocument(sourceStream), Report)

           ' reading values from the detail section
           Dim table As Table = CType(report.Items.Find("table1", True)(0), Table)
           AddHandler table.ItemDataBound, AddressOf Table_ItemDataBound

           ' reading values from a table
           Dim detailSection As DetailSection = CType(report.Items.Find("detailSection1", True)(0), DetailSection)
           AddHandler report.ItemDataBound, AddressOf Report_ItemDataBound

           instanceReportSource.ReportDocument = report
       End Using

    Me.reportViewer1.ReportSource = instanceReportSource
    Me.reportViewer1.RefreshReport()
End Sub

• Accessing data from a table

        private void Table_ItemDataBound(object sender, System.EventArgs e)
        {
            var processsingTable = sender as Telerik.Reporting.Processing.Table;
            foreach (var row in processsingTable.Rows)
            {
                var firstCell = row.GetCell(0);
                var textBoxItem = (Telerik.Reporting.Processing.TextBox)firstCell.Item;
                Trace.WriteLine($"Row: {row.Index}, Cell: {firstCell.RowIndex}, Text: {textBoxItem.Value}");
            }
        }

   Private Sub Table_ItemDataBound(sender As Object, e As EventArgs)
       Dim processingTable As Telerik.Reporting.Processing.Table = CType(sender, Telerik.Reporting.Processing.Table)
       For Each row As Telerik.Reporting.Processing.TableRow In processingTable.Rows
           Dim firstCell As Telerik.Reporting.Processing.TableCell = row.GetCell(0)
           Dim textBoxItem As Telerik.Reporting.Processing.TextBox = CType(firstCell.Item, Telerik.Reporting.Processing.TextBox)
           Trace.WriteLine(String.Format("Row: {0}, Cell: {1}, Text: {2}", row.Index, firstCell.RowIndex, textBoxItem.Value))
       Next
   End Sub

• Accessing data from a textBox item in the detail section of the report

        private void Report_ItemDataBound(object sender, System.EventArgs e)
        {
            var processingReport = sender as Telerik.Reporting.Processing.Report;
            var group = ElementTreeHelper.GetChildByIndex(processingReport, 0);

            var detailSections = ElementTreeHelper.FindChildByName(group, "detailSection1", false);
            foreach (var section in detailSections)
            {
                var textBoxJobTitle = (Telerik.Reporting.Processing.TextBox)ElementTreeHelper.GetChildByName(section, "textBox2");
                Trace.WriteLine($"Detail Section: {((Telerik.Reporting.Processing.DetailSection)section).Name}, Job Title: {textBoxJobTitle.Value}");
            }
        }

Private Sub Report_ItemDataBound(sender As Object, e As System.EventArgs)
    Dim processingReport As Report = CType(sender, Report)
    Dim group As Object = ElementTreeHelper.GetChildByIndex(processingReport, 0)

    Dim detailSections As IEnumerable(Of Object) = ElementTreeHelper.FindChildByName(group, "detailSection1", False)
    For Each section As Object In detailSections
        Dim textBoxJobTitle As TextBox = CType(ElementTreeHelper.GetChildByName(section, "textBox2"), TextBox)
        Trace.WriteLine(String.Format("Detail Section: {0}, Job Title: {1}", CType(section, DetailSection).Name, textBoxJobTitle.Value))
    Next
End Sub

See Also

• Report Parameters Overview
• Report Events Overview