在Inno Setup中将项目添加到列表框的正确方法？

Question

我从List all physical printers using WMI query in Inno Setup获得了一个代码，我想将结果添加到列表框中。我在尝试之前尝试过这样做，但我无法添加所有项目。这是我的代码：

var
  Query, AllPrinters: string;
  WbemLocator, WbemServices, WbemObjectSet: Variant;
  Printer: Variant;
  I: Integer;
begin
  WbemLocator := CreateOleObject('WbemScripting.SWbemLocator');
  WbemServices := WbemLocator.ConnectServer('.', 'root\CIMV2');
  Query := 'SELECT Name FROM Win32_Printer';
  WbemObjectSet := WbemServices.ExecQuery(Query);
  if not VarIsNull(WbemObjectSet) and (WbemObjectSet.Count > 0) then
  begin
    for I := 0 to WbemObjectSet.Count - 1 do
    begin
      Printer := WbemObjectSet.ItemIndex(I);
      if not VarIsNull(Printer) then
      begin
        Log(Printer.Name);
        AllPrinters := Printer.Name;
      end;
    end;
  end;
end;

然后在自定义页面上执行以下操作：

ListBoxPrinters.Items.Add(AllPrinters);

Answer 1

您始终使用下一个值AllPrinters := Printer.Name;覆盖！

简单地构建AllPrinters字符串，就像那样

....
AllPrinters := '';
....
for I := 0 to WbemObjectSet.Count - 1 do
    begin
      Printer := WbemObjectSet.ItemIndex(I);
      if not VarIsNull(Printer) then
      begin
        Log(Printer.Name);
        AllPrinters := AllPrinters + Printer.Name + #13#10;
      end;
    end;
end;

和

ListBoxPrinters.Items.Text := AllPrinters;

Answer 2

您以相同的方式将项目（打印机）添加到列表框中，原始代码将它们添加到日志中：在循环中！

for I := 0 to WbemObjectSet.Count - 1 do
begin
  Printer := WbemObjectSet.ItemIndex(I);
  if not VarIsNull(Printer) then
  begin
    ListBoxPrinters.Items.Add(Printer.Name);
  end;
end;

当然，在迭代打印机之前，您必须使用ListBoxPrinters创建自定义页面。

如果因任何原因无法在创建页面后运行查询，则可以将打印机列表存储到TStringList。

var
  Printers: TStringList;

Printers := TStringList.Create;

for I := 0 to WbemObjectSet.Count - 1 do
begin
  Printer := WbemObjectSet.ItemIndex(I);
  if not VarIsNull(Printer) then
  begin
    Printers.Add(Printer.Name);
  end;
end;

准备好列表框后，只需将列表复制到框中：

ListBoxPrinters.Items.Assign(Printers);