Two simple workarounds for the ReportViewer problems

• Download demo project - 66.6 Kb
• Download source - 81.4 Kb

Introduction

In an application containing the ReportViewer control I have had two following problems :

1. When the ReportViewer is rendering, trying to close the Parent Form of the ReportViewer may cause to crash the Application.
2. There is no straight way to copy the report data to the Clipboard.

Description

Rendering problem :

If there are many pages in a report, it takes a few seconds to render. In this case if the user wants to cancel report rendering and closes the Form containing the ReportViewer control, the Application will crash. To solve this problem I used the RenderingBegin and RenderingComplete events of the ReportViewer and the FormClosing event of the Parent Form.

To see how the problem is occurred, consider the included source files. After running the project there are nineteen pages in the report. (32 pages in the print layout mode). By clicking the 'Print Layout' button, the report begins rendering. While the report is rendering, if the user closes the Parent Form, the Application will crash (If we comment added event handlers).

Copy to the Clipboard :

In a report, there is no straight way to copy the report data to the Clipboard. The only way that is available is using the Hyperlink event of the ReportViewer control (There is an related article by Teo Lachev at http://www.devx.com/dotnet/Article/30424/0/page/6) . To do this, we should set some attributes at the design time :

• Suppose that there is a 'table' item on the report file. Select each TextBox from the 'Table Details' row.

• Go to the Properties -> Navigation -> 'Hyperlink action' -> 'Jump to URL'.

• In the following ComboBox write '= "NoLink:" & Fields!FieldName.Value' . (Replace FieldName with the name of field)

Using the code

For the rendering problem, a variable named IsRendering is defined. In the RenderingBegin we set IsRendering = false. While report is rendering it prevents closing the form by user. The code is as below :

<summary>
</summary>bool IsRendering = false;<summary>

// It cancels the FormClosing while the ReportViewer is rendering.   
</summary>private void ReportForm_FormClosing(object sender, FormClosingEventArgs e)
{
    if (IsRendering) e.Cancel = true;
}

<summary>// When rendering begins it sets IsRendering = true.
</summary>private void reportViewer1_RenderingBegin(object sender, CancelEventArgs e)
{
    IsRendering = true;
}

<summary>// When rendering is completed it sets IsRendering = false.
</summary>private void reportViewer1_RenderingComplete(object sender,
                                        RenderingCompleteEventArgs e)
{
    IsRendering = false;
}

For the copy problem, after setting the required attributes at the design time, we write below code in the reportViewer1_Hyperlink event handler :

<summary>// Copy the report data to the Clipboard.
</summary>private void reportViewer1_Hyperlink(object sender, HyperlinkEventArgs e)
{
    Uri uri = new Uri(e.Hyperlink);
    if (uri.Scheme.ToLower() == "nolink")
    {
        e.Cancel = true;
        Clipboard.Clear();
        Clipboard.SetText(uri.AbsolutePath);
    }
}