显示窗口后如何组织此代码以加载报告？

Question

Im trying to load a xml file into a dataset and generate crystal report with loaded data.

im using Crystal Reports WPF Application for the project.

public partial class Window1 : Window
{
    public Window1()
    {
        InitializeComponent();
        reportViewer.Owner = this;

        DataSet dset = new DataSet1();

        DataSet reportData = new DataSet();
        reportData.ReadXml("http://192.168.1.10/test/persons.xml");

        dset.Tables[0].Merge(reportData.Tables[0]); 


        ReportDocument report = null;
        report = new CrystalReport1();
        report.SetDataSource(dset.Tables[0]);
        reportViewer.ViewerCore.ReportSource = report;
    }

}

This working fine and my question is how to move download xml and set report codes to a different event to load report after the application is shown?

Regards

Answer 1

Here is the Window Lifetime Management events: ( MSDN )

• Activated
• Closed
• Closing
• Deactivated
• SourceInitialized

I believe Activated event is what you need. Considering that Activated event fires not only when a window opened first time but also when ALT + TAB switches and so on so to filter out first windo opening from other Activated events just use boolean flag setting it to true when first time Activated event was handled:

    bool firstActivateAlreadyHandled = false;
    protected override void OnActivated(EventArgs e)
    {
        base.OnActivated(e);

        if (!this.firstActivateAlreadyHandled)
        {
             // your code here
             this.firstActivateAlreadyHandled = true;
        }
    }

Answer 2

Not 100% certain what you are after, if you want to handle the download of the file elsewhere then you could read the remote file, save it locally and then once saved update the report then, if you are looking at just handling the remote file once the window shows then i'm not sure, i'm assuming you mean a form which means on a form you would do something like this:

Private void Form1_Shown(object sender, EventArgs e)
{
            DataSet dset = new DataSet1();

            DataSet reportData = new DataSet();
            reportData.ReadXml("http://192.168.1.10/test/persons.xml");

            dset.Tables[0].Merge(reportData.Tables[0]); 


            ReportDocument report = null;
            report = new CrystalReport1();
            report.SetDataSource(dset.Tables[0]);
            reportViewer.ViewerCore.ReportSource = report;

}

As you have said it is for WPF try....

private void Window_Loaded(object sender, RoutedEventArgs e)
{
            DataSet dset = new DataSet1();

            DataSet reportData = new DataSet();
            reportData.ReadXml("http://192.168.1.10/test/persons.xml");

            dset.Tables[0].Merge(reportData.Tables[0]); 


            ReportDocument report = null;
            report = new CrystalReport1();
            report.SetDataSource(dset.Tables[0]);
            reportViewer.ViewerCore.ReportSource = report;
}

or

private void Window_ContentRendered(object sender, RoutedEventArgs e)
{
            DataSet dset = new DataSet1();

            DataSet reportData = new DataSet();
            reportData.ReadXml("http://192.168.1.10/test/persons.xml");

            dset.Tables[0].Merge(reportData.Tables[0]); 


            ReportDocument report = null;
            report = new CrystalReport1();
            report.SetDataSource(dset.Tables[0]);
            reportViewer.ViewerCore.ReportSource = report;
}

Answer 3

If you are concerned about UI response ie your loading stops the application flow, you can start it in a different thread. Just wrap it like this.

public Window1()
{
    InitializeComponent();

    new Task(() =>
    {
        Dispatcher.BeginInvoke(new Action(() =>
        {
            reportViewer.Owner = this;

            DataSet dset = new DataSet1();

            DataSet reportData = new DataSet();
            reportData.ReadXml("http://192.168.1.10/test/persons.xml");

            dset.Tables[0].Merge(reportData.Tables[0]);


            ReportDocument report = null;
            report = new CrystalReport1();
            report.SetDataSource(dset.Tables[0]);
            reportViewer.ViewerCore.ReportSource = report;
        }), null);
    }).Start();
}