CustomPrintMultiGrid
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Use the CreateImage method to print multiple grids in a single document.

The PrintGrid method allows you to customize several parameters when
printing and previewing grids. However, it only allows you to print one
grid per document.

This sample implements a class derived from PrintDocument that can be used 
to print or preview multiple grids, with page breaks set at specific
rows and columns.

The PrintDocument class creates grid images for each page and sets the zoom
level so all images will fit on the page.
