You have to put Repeater control inside the Main listView cotrol. And then you need to add code for
listview_rowdataboud(..)
{
Repeater repcomment = e.row.findcontrol("your repeater control id");
repcommnet.DataSource = getComment(id)
repcommnet.DataBind();
}
getComment(int id)
{
return dt;
}
Note: this is code snippet, it something link this, you have to write proper code for the same.
Thanks,
Imdadhusen