带CheckBox全选功能

var
i:Integer;
begin
 for I := 0 to lstqq.Items.Count - 1 do
   begin
     lstqq.Items[i].Checked:=True;
   end;
end;

删除所选:

var
i:Integer;
begin
 for i :=lstqq.items.Count - 1 downto 0 do
 begin
   if lstqq.Items[i].Checked then lstqq.Items.Delete(i);
 end;
end;

Listview导出数据到文本:

var
  i, j: integer;
  s: string;
  temp,temp1: string;
begin
  temp := '';
  for I := 0 to Lstqq.Items.Count - 1 do
  begin
    for j := 0 to lstqq.Items[i].SubItems.Count - 1 do
    begin
    temp1:=lstqq.Items.Item[i].Caption;
    temp:=lstqq.Items.Item[i].SubItems.Strings[j];
    s:=temp1+','+temp;
    AppendTxt(s,'log.txt')
    end;
  end;
end;
procedure TFrmMain.AppendTxt(Str, FileName: String);
var
  f:TextFile;
begin
  if not FileExists(FileName) then FileCreate('log.txt');
  AssignFile(f, FileName); //把一个外部文件和一个变量关联起来。
  Append(f);     //追加方式打开一个文件
  Writeln(f, Str); //把字符串写入到变量F
  Closefile(f);   //关闭文件
end;