Delphi下POS机控制钱箱,客显,打印机,小票打印

1、控制POS机的客户显示屏
procedure TFrmMain.ShowMoney(Money_Port:   String;Money_String:String);
//Moneey_Port     顾显接口Com1   or   Com2     Money_String     顾显显示的内容
var
    PrnFileName:TextFile;
begin
    Assignfile(PrnFileName,Money_Port);
    printer.Canvas.Font.Name:='宋体';
    printer.Canvas.Font.Size:=8;
    printer.Canvas.Font.Charset:=GB2312_CHARSET;
    Rewrite(PrnFileName);
    write(PRNFileName,chr(12));         //清除顾显
    write(PRNFileName,chr(27)+chr(81)+chr(65)+Money_String+chR(13));       //显示信息
    CloseFile(PRNFileName);
end;
2、不换页走纸的打印
procedure TFrmMain.AddPrintStrings(Strings: TStrings);
var
Prn: TextFile;
i: word;
begin
Assignfile(Prn,'lpt1');
    printer.Canvas.Font.Name:='宋体';
    printer.Canvas.Font.Size:=9;
    printer.Canvas.Font.Charset:=GB2312_CHARSET;
try
    Rewrite(Prn);
    try
      for i := 0 to Strings.Count - 1 do
        writeln(Prn, Strings.Strings[i]);
    finally
      CloseFile(Prn);
    end;
except
    on EInOutError do
      MessageBox(Handle,PChar('文本打印出错!'),'警告',MB_ICONEXCLAMATION or MB_OK);
end;
end;
3、走纸换页的打印
procedure TFrmMain.PrintStrings(Strings: TStrings);
var
Prn: TextFile;
i: word;
begin
AssignPrn(Prn);
try
    Rewrite(Prn);
    printer.Canvas.Font.Name:='宋体';
    printer.Canvas.Font.Size:=9;
    printer.Canvas.Font.Charset:=GB2312_CHARSET;
&nb