Programmatically set Custom Paper Size for Crystal Report

This Method works with an Epson LX-300+ ii Dot-Matrix Printer and later models

If you are using a Printer especially for Printing Receipts here are the steps on how to set your printer for desired paper size

First Set up Printer to be used: Go to Devices and Printers in Printers select the Printer you are going to use and click - right click Printer Properties Click Preferences... Button. Under Main Tab - Change Document Size to User Defined a new New Window will appear. in Paper Size Name specify the name (i.e. OR Paper) and change paper width and height as desired Click Save then OK

enter image description here then set your printer by Pressing right click then set as Default Printer

Add these line of code for your printing. You can still use parameters and datasets.

Dim c As Integer
    Dim doctoprint As New System.Drawing.Printing.PrintDocument()
    doctoprint.PrinterSettings.PrinterName = "EPSON L1300 Series"
    Dim rawKind As Integer
    For c = 0 To doctoprint.PrinterSettings.PaperSizes.Count - 1
        If doctoprint.PrinterSettings.PaperSizes(c).PaperName = "OR Receipts" Then
            rawKind = CInt(doctoprint.PrinterSettings.PaperSizes(c).GetType().GetField("kind", Reflection.BindingFlags.Instance Or 

Reflection.BindingFlags.NonPublic).GetValue(doctoprint.PrinterSettings.PaperSizes(c)))
            Exit For
        End If
    Next

    Report1.PrintOptions.PaperSize = CType(rawKind, CrystalDecisions.Shared.PaperSize)
    frmPreview.CrystalReportViewer1.ReportSource = Report1
    Report1.PrintToPrinter(1, False, 1, 1)

you can do as this

var rep = new YursCrystalReport();
var printerSettings = new System.Drawing.Printing.PrinterSettings();
var pSettings = new System.Drawing.Printing.PageSettings(printerSettings); 
pSettings.PaperSize = new System.Drawing.Printing.PaperSize("newsize", 3000, 3000);//custom size  hundredths (100=1 inch)
pSettings.Margins = new System.Drawing.Printing.Margins(0, 0, 0, 0);
rep.PrintOptions.DissociatePageSizeAndPrinterPaperSize = true;
rep.PrintOptions.CopyFrom(printerSettings, pSettings);