dxDBgrid多选，删除每条选中记录

 with dxDBGrid1.DataSource.DataSet do
      begin
        for I:=0 to dxDBGrid1.SelectedCount-1 do
        begin
          GoTobook(pointer(dxDBGrid1.SelectedRows[i]));
//          Edit;
//          FieldByName('Name').AsString := Str;
//          Post;
        end;
      end;如题
我查询相关资料
为什么我用
GoTobook(pointer(dxDBGrid1.SelectedRows[i]));这段代码就报错
如果单独输入dxDBGrid1.SelectedRows[i]);正确
可是如果转格式pointer(dxDBGrid1.SelectedRows[i]));就出错
求教下各位达人...
感激...