Added new kb article accessing-values-winforms-report-viewer

knowledge-base/accessing-values-winforms-report-viewer.md

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+---
+title: Accessing Data from Rendered Report in WinForms Viewer
+description: "Learn how to access values from a rendered TRDP or TRDX report in the WinForms Report Viewer by using report parameters or report events."
+type: how-to
+page_title: Extract Values from WinForms Report Viewer Processed Report
+meta_title: Extract Values from WinForms Report Viewer Processed Report
+slug: accessing-values-winforms-report-viewer
+tags: reporting, winforms, report viewer, parameters, report items
+res_type: kb
+ticketid: 1693205
+---
+
+## Environment
+
+<table>
+   <tbody>
+      <tr>
+         <td>Product</td>
+         <td>Reporting</td>
+      </tr>
+   </tbody>
+</table>
+
+## 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]({%slug telerikreporting/designing-reports/connecting-to-data/report-parameters/overview%}) to retrieve values from the report. Connect the report parameter to the desired field of the [data source component]({%slug telerikreporting/designing-reports/connecting-to-data/data-source-components/overview%}) whose data you need to access.
+
+1. [Create a report parameter]({%slug telerikreporting/designing-reports/connecting-to-data/report-parameters/how-to-add-report-parameters%}) in the report designer, connect it to the needed [data source component]({%slug telerikreporting/designing-reports/connecting-to-data/data-source-components/overview%}), and bind its [Value](/api/telerik.reporting.reportparameter#Telerik_Reporting_ReportParameter_Value) and [ValueMember](/api/telerik.reporting.reportparameteravailablevalues#Telerik_Reporting_ReportParameterAvailableValues_ValueMember) properties to the required field. You may use the same expression for both properties - `= Fields.MyField`.
+1. Access the report parameter value in the application code through the viewer's [ReportSource](/api/telerik.reportviewer.winforms.reportviewerbase#Telerik_ReportViewer_WinForms_ReportViewerBase_ReportSource) property:
+
+
+````VB
+   Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
+       Dim reportParameterValue = Me.ReportViewer1.ReportSource.Parameters("MyParameter").Value
+   End Sub
+````
+````C#
+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]({%slug telerikreporting/using-reports-in-applications/program-the-report-definition/report-events/overview%}). For TRDP/TRDX files, they must be unpackaged/deserialized in order to assign custom event handlers to the reports.
+
+````C#
+        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();
+        }
+````
+````VB
+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
+
+````C#
+        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($"Row: {row.Index}, Cell: {firstCell.RowIndex}, Text: {textBoxItem.Value}");
+            }
+        }
+````  
+````VB
+   Private Sub Table_ItemDataBound(sender As Object, e As EventArgs)
+       Dim processingTable As Telerik.Reporting.Processing.Table = CType(sender, Telerik.Reporting.Processing.Table)
+       For Each row As Telerik.Reporting.Processing.TableRow In processingTable.Rows
+           Dim firstCell As Telerik.Reporting.Processing.TableCell = row.GetCell(0)
+           Dim textBoxItem As Telerik.Reporting.Processing.TextBox = CType(firstCell.Item, Telerik.Reporting.Processing.TextBox)
+           Trace.WriteLine(String.Format("Row: {0}, Cell: {1}, Text: {2}", row.Index, firstCell.RowIndex, textBoxItem.Value))
+       Next
+   End Sub
+````
+
+
+- Accessing data from a `textBox` item in the **detail** section of the report
+
+````C#
+        private void Report_ItemDataBound(object sender, System.EventArgs e)
+        {
+            var processingReport = sender as Telerik.Reporting.Processing.Report;
+            var group = ElementTreeHelper.GetChildByIndex(processingReport, 0);
+
+            var detailSections = ElementTreeHelper.FindChildByName(group, "detailSection1", false);
+            foreach (var section in detailSections)
+            {
+                var textBoxJobTitle = (Telerik.Reporting.Processing.TextBox)ElementTreeHelper.GetChildByName(section, "textBox2");
+                Trace.WriteLine($"Detail Section: {((Telerik.Reporting.Processing.DetailSection)section).Name}, Job Title: {textBoxJobTitle.Value}");
+            }
+        }
+````
+````VB
+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]({%slug telerikreporting/designing-reports/connecting-to-data/report-parameters/overview%})
+* [Report Events Overview]({%slug telerikreporting/using-reports-in-applications/program-the-report-definition/report-events/overview%})