Tray Switching from C#, Crystal Reports

We have a Crystal Report which is called from a C# Windows Forms application (VS 2008).

We also have a Xerox 4127 printer with around eight trays which can feed A4 size paper into the printer.

The aim is to print on five different types of stock (all A4 size), each type of stock from its own tray. So effectively Stock 1 goes into Tray 1, Stock 2 goes into Tray 2 and so on.

The WinForms app loads the Crystal Report and just before each page is printed, it dynamically sets the PaperSize and PaperSource properties on the report. It should now do the job.

The problem with the Xerox printer is that the trays are colour coded. For e.g. Tray 1 is Red, Tray 2 is Blue, Tray 3 is Green, Tray 4 is White and so on. How do we include these colour codes into the application so that the correct tray from the printer can be used?

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