Can Check Rows Returned In A QueryString Parameter Based Entity Framework Query

I need to check if any rows are returned in a QueryString here's what I have so far.not sure what code to put to see if the row count is greater than 1

private void BindDataToGrid()
{
//MessageBoardEntities3 is ThemeableAttribute connection string name
int TID = Convert.ToInt32(Request.QueryString["ThreadID"].ToString()); // if Post ID is int
var context = new MessageBoardEntities3();
gvPosts.DataSource = from p in context.Posts
where p.ThreadID == TID
select new { p.Post1, p.PostID };
gvPosts.DataBind();
lblNoPosts.Text = "No posts found for this thread.";
}