MultiGridDocument
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Shows how to render multiple grids into a single PrintDocument.

The C1FlexGrid always provided a PrintGrid method which is still available. 
That is the easiest way to print and preview a grid. For example:

private void button1_Click(object sender, EventArgs e)
{
	c1FlexGrid1.PrintGrid("Traditional", 
		PrintGridFlags.FitToPageWidth | 
        PrintGridFlags.ExtendLastCol | 
        PrintGridFlags.ShowPreviewDialog);
}

This method automatically creates and prepares a PrintDocument object that contains 
a single FlexGrid. But it does not allow you to combine the grid with other content
elements on the document, including other grids.

This sample shows how you can use the new PrintDocumentGridRenderer class to render
multiple grids into one existing PrintDocument. All you need to do is create one 
PrintDocumentGridRenderer for each grid, then call the PrintPage method in response
to the PrintDocument's PrintPage event.

The sample also uses a CoolPrintPreviewDialog class that enhances the standard 
PrintPreviewDialog class to provide faster rendering, a better looking and more 
functional UI, and the ability to export the document to PDF.
