打印时改变纸张大小

// 在执行打印前调用以下函数：
// x,y:纸张尺寸,单位是0.1mm
procedure SetPaperSize(X, Y: Integer);
var
Device: array[0..255] of char;
Driver: array[0..255] of char;
Port: array[0..255] of char;
hDMode: THandle;
PDMode: PDEVMODE;
begin
Printer.PrinterIndex := Printer.PrinterIndex;
Printer.GetPrinter(Device, Driver, Port, hDMode);
if hDMode <> 0 then
begin
pDMode := GlobalLock(hDMode);
if pDMode <> nil then
begin
if (x = 0) or (y = 0) then
begin
{设置合法的纸张大小}
pDMode^.dmFields := pDMode^.dmFields or dm_PaperSize;
pDMode^.dmPaperSize := DMPAPER_FANFOLD_US; // 合法的纸张大小标示
end
else
begin
{设置用户自定义纸张}
pDMode^.dmFields := pDMode^.dmFields or DM_PAPERSIZE or DM_PAPERWIDTH or DM_PAPERLENGTH;
pDMode^.dmPaperSize := DMPAPER_USER; // 设置为用户自定义纸张标示
pDMode^.dmPaperWidth := x; // 纸张宽度
pDMode^.dmPaperLength := y; // 纸张长度
end;
{设定纸张来源}
pDMode^.dmFields := pDMode^.dmFields or DMBIN_MANUAL;
pDMode^.dmDefaultSource := DMBIN_MANUAL;

GlobalUnlock(hDMode);
end;
end;
end;