Exploration of New Methods in Crystal Reports WPF Viewer
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by Eric Landes
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Creating a new Reporting Application with the WPF Viewer

To create a new project, select the "Crystal Reports WPF Application" from the new projects menu.  It can be found under the Reporting category of your installed templates.  After creating the project, the new solution has a WPF class, and a Crystal Report should be visible in the Solution Explorer.  That WPF file has a WPF Crystal Viewer bound to it.  Let me warn you that creating a WPF solution from Visual Studio templates then trying to add the Crystal viewer to that solution is tricky to implement.  It is much easier to just use the templates provided from SAP.

The new WPF viewer control to use in your windows applications is a slick new control.  It looks better and has some newer features, as revealed in the API section above.  Binding a report to the viewer is done most easily programmatically. 

If you want to allow the end user some control of what report to view, enable the property ShowOpenFileButton to allow the user to select a report.  Eventually there will be a property to set this, but you can set the report to an embedded resource using code.  For instance, in example 1, the code shows how to bind an embedded resource to the report viewer. 

CrystalReport1 is a report created in a project.  To bind this report to the new WPF viewer, use the property ViewerCore.ReportSource and set it to the instance of the embedded report.  Code Sample 1 shows the code.

Code Sample 1

            InitializeComponent();
            reportViewer.Owner = this;
            CrystalReport1 newCR = new CrystalReport1();
            reportViewer.ViewerCore.ReportSource = newCR;

Once you have set the code to bind this report to your viewer, you are now ready to use some of the new WPF properties.  Let's go through each property and find the methods where it is best to use them.

NumberOfPages

Once you have set up a CR Project and created the initial code to bind your report, you can now start experimenting with the new API methods and events available to you.  All of these properties are from the ReportRequest class and will return some data available from the Report document being rendered.  In this case we start with ReportDocument.ReportRequestStatus.NumberOfPages

In working with this method, it appears that until the report has been renedered, this method will only return a 0.  Once rendered, then the number of pages in total that the report has will be returned. 

For example, the code displayed in the LayoutUpdated method of the viewer (see this in code example 2), fires multiple times during startup.  Hovering over this method in debug mode until the viewer renders the report, we see that the count is 0.  This can be a useful way to programmitcally get page numbers from  reports with large datasets that vary.

Code Sample 2

Private void reportViewer_LayoutUpdated(object sender, EventArgs e)
{
      Int numPages = newCR.ReportRequestStatus.NumberOfPages;

}

Use this after LayoutUpdated, or Refresh to determine how many pages are now displaying in the viewer.

NumberOfRecordsRead

This property can be used, in the event LayoutUpdated, and is populated after parameters are filled out.  Other events where this can be useful are in the Refresh, and RequestBringIntoView event. 

As noted above, the LayoutUpdated method fires multiple times during loading of the report.  Only after the parameter is selected have I found that this property is populated.  Since the Viewer event Loaded fires before parameters are selected, this property is not populated during that event.

This property can be useful during events like RequestBringIntoView, and Refresh also.  Any event that fires after these should also be able to utilize this property.  This could be helpful during backend processing, if you are writing logs, or if any kind of error is encountered to help troubleshoot those kind of issues.

Code Sample 3

Private void reportViewer_LayoutUpdated(object sender, EventArgs e)
{
      Int numPages = newCR.ReportRequestStatus.NumberOfPages;
      Int numRecordsRead = newCR.ReportRequestStatus.NumberOfRecordsRead;
}

NumberOfRecordsSelected

This property is very similar to NumberOfRecordsRead.  In fact in the course of this article, the results from this property were not different than that of NumberOfRecordsRead for the Refresh, RequestBringIntoView, Loaded, SelectionChanged and LayoutUpdated methods. While there may be a difference and a good place to utilize this, it is not within these methods. 

Below is some sample code for how you can utilize this property.  It is very similar to NumberOfRecordsRead.

Code Sample 4

Private void reportViewer_SelectionChange(object sender, RoutedEventArgs e)
{
      Int numRecordsSelecteds = newCR.ReportRequestStatus.NumberOfRecordsSelected;

}


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