C# 4 and .NET 4

Printing ❘ OC45
}
if (nLines > 0)
{
documentHasData = true;
menuFilePrint.Enabled = true;
menuFilePrintPreview.Enabled = true;
}
else
{
documentHasData = false;
menuFilePrint.Enabled = false;
menuFilePrintPreview.Enabled = false;
}
CalculateLineWidths();
CalculateDocumentSize();
Text = standardTitle + "-" + FileName;
Invalidate();
code download Printing.sln
The above code is the new code added to this method. Next, you add a member field to the Form1 class:
public partial class Form1: Form
{
private int pagesPrinted = 0;
This field will be used to indicate which page you are currently printing. You are making it a member field
because you will need to remember this information between calls to the PrintPage event handler.
Next, you will find the event handlers that handle the selection of the Print or Print Preview menu options:
private void menuFilePrintPreview_Click(object sender, System.EventArgs e)
{
this.pagesPrinted = 0;
PrintPreviewDialog ppd = new PrintPreviewDialog();
PrintDocument pd = new PrintDocument();
pd.PrintPage += this.pd_PrintPage;
ppd.Document = pd;
ppd.ShowDialog();
}
private void menuFilePrint_Click(object sender, System.EventArgs e)
{
this.pagesPrinted = 0;
PrintDocument pd = new PrintDocument();
pd.PrintPage += new PrintPageEventHandler
(this.pd_PrintPage);
pd.Print();
}
code download Printing.sln
You have already seen the steps involved in printing, and you can see that these event handlers are simply
implementing that procedure. In both cases, you are instantiating a PrintDocument object and attaching an
event handler to its PrintPage event. In the case of printing, you call PrintDocument.Print(), whereas
for print previewing, you attach the PrintDocument object to a PrintPreviewDialog and call the preview
dialog box object’s ShowDialog() method. The real work to the PrintPage event is done in the event
handler. Here is how this handler looks:
private void pd_PrintPage(object sender, PrintPageEventArgs e)
{
float yPos = 0;
float leftMargin = e.MarginBounds.Left;
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