Invoke a Default Document Preview

• Aug 18, 2023
• 4 minutes to read

This topic describes how to display a report in the Document Preview window that is supplied with DevExpress Reporting for WPF applications.

Basic Methods

Use the PrintHelper class methods to display a report in one of the default Document Preview windows.

Note

Do the following to use the PrintHelper class in your application depending on the target framework:

• .NET Framework – add the DevExpress.Xpf.Printing.v24.1.dll and DevExpress.Xpf.Core.v24.1.dll assemblies to the application References list.
• .NET 6+ – add the DevExpress.Wpf.Reporting NuGet package to your application.

Refer to the WPF Reporting Application Deployment topic for a full list of libraries required to load a Document Preview.

• The PrintHelper.ShowRibbonPrintPreview and PrintHelper.ShowRibbonPrintPreviewDialog methods show a window with a Ribbon toolbar.

  

• The PrintHelper.ShowPrintPreview and PrintHelper.ShowPrintPreviewDialog methods invoke a window with a standard toolbar.

  

Preview Light-Weight Reports

Call one of the PrintHelper‘s methods detailed above passing a report instance as a parameter to show a Document Preview window with the report.

The following code illustrates how to call these methods in the main application window’s Loaded event handler:

C#

using DevExpress.Xpf.Printing;
// ...

private void Window_Loaded(object sender, System.Windows.RoutedEventArgs e) {
    // Invoke the Ribbon Print Preview window 
    // and load the report document into it.
    PrintHelper.ShowRibbonPrintPreview(this, new XtraReport1());

    // Invoke the Ribbon Print Preview window modally.
    PrintHelper.ShowRibbonPrintPreviewDialog(this, new XtraReport1());

    // Invoke the standard Print Preview window 
    // and load the report document into it.
    PrintHelper.ShowPrintPreview(this, new XtraReport1());

    // Invoke the standard Print Preview window modally.
    PrintHelper.ShowPrintPreviewDialog(this, new XtraReport1());
}

VB.NET

Imports DevExpress.Xpf.Printing
' ...

Private Sub Window_Loaded(sender As Object, e As System.Windows.RoutedEventArgs)
    ' Invoke the Ribbon Print Preview window 
    ' and load the report document into it.
    PrintHelper.ShowRibbonPrintPreview(Me, New XtraReport1())

    ' Invoke the Ribbon Print Preview window modally.
    PrintHelper.ShowRibbonPrintPreviewDialog(Me, New XtraReport1())

    ' Invoke the standard Print Preview window 
    ' and load the report document into it.
    PrintHelper.ShowPrintPreview(Me, New XtraReport1())

    ' Invoke the standard Print Preview window modally.
    PrintHelper.ShowPrintPreviewDialog(Me, New XtraReport1())
End Sub

Tip

Calling any of these methods generates document pages by calling the XtraReport.CreateDocument method internally if they are not generated yet.

The Document Preview displays pages as soon as they are generated.

Preview Large Reports

Use the CachedReportSource component to preview reports that include a large amount of data. This component allows you to avoid memory consumption-related issues by storing pages in a file system or database during document generation.

Create a CachedReportSource instance specifying a report to be previewed and a storage to cache the report document.

C#

using DevExpress.XtraReports.UI;
using DevExpress.XtraPrinting.Caching;
//...
    var storage = new MemoryDocumentStorage();
    var report = new XtraReport1();
    var cachedReportSource = new CachedReportSource(report, storage); 

VB.NET

Imports DevExpress.XtraReports.UI
Imports DevExpress.XtraPrinting.Caching
'...
    Private storage = New MemoryDocumentStorage()
    Private report = New XtraReport1()
    Private cachedReportSource = New CachedReportSource(report, storage)

The MemoryDocumentStorage object used in this code stores a document in memory in a compact way. You can use the FileDocumentStorage, DbDocumentStorage, or implement a custom storage instead.

Call one of the PrintHelper‘s methods detailed above passing a CachedReportSource instance as a parameter to show a Document Preview window with the associated report.

C#

using DevExpress.Xpf.Printing;
using DevExpress.XtraReports.UI;
using DevExpress.XtraPrinting.Caching;
// ...

private void Window_Loaded(object sender, System.Windows.RoutedEventArgs e) {
    var storage = new MemoryDocumentStorage();
    var report = new XtraReport1();
    var cachedReportSource = new CachedReportSource(report, storage); 

    // Invoke the Ribbon Print Preview window 
    // and load the report document into it.
    PrintHelper.ShowRibbonPrintPreview(this, cachedReportSource);

    // Invoke the Ribbon Print Preview window modally.
    PrintHelper.ShowRibbonPrintPreviewDialog(this, cachedReportSource);

    // Invoke the standard Print Preview window 
    // and load the report document into it.
    PrintHelper.ShowPrintPreview(this, cachedReportSource);

    // Invoke the standard Print Preview window modally.
    PrintHelper.ShowPrintPreviewDialog(this, cachedReportSource);
}

VB.NET

Imports DevExpress.Xpf.Printing
Imports DevExpress.XtraReports.UI
Imports DevExpress.XtraPrinting.Caching
' ...
    Dim storage = New MemoryDocumentStorage()
    Dim report = New XtraReport1()
    Dim cachedReportSource = New CachedReportSource(report, storage)

    ' Invoke the Ribbon Print Preview window 
    ' and load the report document into it.
    PrintHelper.ShowRibbonPrintPreview(Me, cachedReportSource)

    ' Invoke the Ribbon Print Preview window modally.
    PrintHelper.ShowRibbonPrintPreviewDialog(Me, cachedReportSource)

    ' Invoke the standard Print Preview window.
    ' and load the report document into it.
    PrintHelper.ShowPrintPreview(Me, cachedReportSource)

    ' Invoke the standard Print Preview window modally.
    PrintHelper.ShowPrintPreviewDialog(Me, cachedReportSource)
End Sub

Tip

Calling any of these methods generates document pages by calling the CachedReportSource.CreateDocumentAsync method internally if they are not generated yet.

When a Document Preview is associated with a CachedReportSource component, only visible pages are stored in memory.