Solved: getting printer trays

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Buropro-Citation🇨🇦

getting printer trays

Hi everyone, I was using the code sample below in earlier version of Delphi to get the trays associated with a specific printer. This code doesn't work under Delphi in some case I'm getting an access violation error and my application will not work until I'm shutting it down.

What I would need is a correction to this code ot any code that would let me get a lit of all the tray name from a printer.

I kinow the error is exactly on the getmem, I think delphi XE have different ways to manage caracters strings.

Thank you for any help on this matter.

GetMem(p,24*DeviceCapabilities(pchar(PName),nil,DC_BINNAMES,nil,nil));
  for i:=1 to DeviceCapabilities(pchar(PName),nil,DC_BINNAMES,p,nil) do
  begin
    ComboName.items.add(p+24*(i-1));
  end;
  FreeMem(p);

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Thommy🇩🇪

Please check, if this helps you...

http://www.swissdelphicenter.ch/de/showcode.php?id=796

ASKER CERTIFIED SOLUTION

Thommy🇩🇪

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Thommy🇩🇪

To finally change printer bin try following function...

http://www.efg2.com/Lab/Library/UseNet/1999/1102.txt

Buropro-Citation🇨🇦

ASKER

It works perfectly, there was a slight error in the code but it was easy to correct, thank you Thommy :)

Here is the corrected code:
procedure TfMAin.GetPaperBins(sl: TStrings; PrinterName: String);
type
TBinName = array [0..23] of Char;
TBinNameArray = array [1..High(Integer) div SizeOf(TBinName)] of TBinName;
PBinnameArray = ^TBinNameArray;
TBinArray = array [1..High(Integer) div SizeOf(Word)] of Word;
PBinArray = ^TBinArray;
var
Device, Driver, Port: array [0..255] of Char;
hDevMode: THandle;
i, numBinNames, numBins, temp: Integer;
pBinNames: PBinnameArray;
pBins: PBinArray;
begin
//set specified printer
for numBins := 0 to Printer.Printers.Count -1 do begin
if Printer.Printers [numBins] = PrinterName then
Printer.PrinterIndex := numBins ;
end;
//original Code
Printer.GetPrinter(Device, Driver, Port, hDevmode);
numBinNames := WinSpool.DeviceCapabilities(Device, Port, DC_BINNAMES, nil, nil);
numBins := WinSpool.DeviceCapabilities(Device, Port, DC_BINS, nil, nil);
if numBins <> numBinNames then
begin
raise Exception.Create('DeviceCapabilities reports different number of bins and bin names!');
end;
if numBinNames > 0 then
begin
pBins := nil;
GetMem(pBinNames, numBinNames * SizeOf(TBinname));
GetMem(pBins, numBins * SizeOf(Word));
try
WinSpool.DeviceCapabilities(Device, Port, DC_BINNAMES, PChar(pBinNames), nil);
WinSpool.DeviceCapabilities(Device, Port, DC_BINS, PChar(pBins), nil);
sl.Clear;
for i := 1 to numBinNames do
begin
temp := pBins^[i];
sl.addObject(pBinNames^[i], TObject(temp));
end;
finally
FreeMem(pBinNames);
if pBins <> nil then
FreeMem(pBins);
end;
end;
end;

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