在DELPHI中如何检测是系统是否安装打印机

Question

如题!

Answer 1

HKEY_LOCAL_MACHINE\Config\0001\System\CurrentControlSet\Control\Print\Printers
下的default的值是否为空

Answer 2

var
  Device:array[0..cchDeviceName-1]of char;
  Driver:array[0..MAX_PATH-1] of char;
  port:array[0..32] of char;
  hDMode:THandle;
begin
   printer.GetPrinter(Device,Driver,port,hDMode);
   if printer.PrinterIndex=0 then
    Messagedlg('你需要安装打印机才能打印！',mtError,[mbOk],0);

Answer 3

if  printer.Printers.Count = 0 then 
    Messagedlg('你需要安装打印机才能打印！',mtError,[mbOk],0);

Answer 4

转贴
function TFBillPreview.CheckPrinterConnect: Boolean;
  function GetCurrentPrinterHandle: THandle;
  var
    Device, Driver, Port : array[0..215] of char;
    hDeviceMode: THandle;
  begin
    Printer.GetPrinter(Device, Driver, Port, hDeviceMode);
    OpenPrinter(@Device, Result, nil);
  end;
type
  TJobs = Array [0..1000] of JOB_INFO_1;
  PJobs = ^TJobs;
var
  hPrinter : THandle;
  bytesNeeded, numJobs: Cardinal;
  pJ: PJobs;
begin
  CheckPrinterConnect := False;
  hPrinter:= GetCurrentPrinterHandle;
  try
    EnumJobs( hPrinter, 0, 1000, 1, nil, 0, bytesNeeded, numJobs );
    pJ := AllocMem( bytesNeeded );
    If EnumJobs( hPrinter, 0, 1000, 1, pJ, bytesNeeded, bytesNeeded, numJobs ) then
      CheckPrinterConnect := True;
  finally
    ClosePrinter( hPrinter );
  end;
end;

Answer 5

kaiyun97(黑马不黑)的方法简洁明快！看TPrinter的定义：TPrinter = class(TObject)
private
  ...
  function GetPrinters: TStrings;
  ...
public
  property Printers: TStrings read GetPrinters;
  ...
end; hongqi162(失踪的月亮)的答案冗长且printer.PrinterIndex=0 会得出错误的结论