how to add control runtime(dynamically)

i am trying to add control(textbox ,button "Remove") 3times in runtime with the help of add button. and adding someting text in text box but when i am clicking button "Remove" then all added control goes to erase.

how to achiev solution for this problem ?

 Button btn = new Button();
                 Table tblName = new Table();
                 PlaceHolder PlaceHolder1 = new PlaceHolder();
                 btn.Click += new EventHandler(btn_Click);
                 TableRow tr = new TableRow();
                 tr.Cells.Add(new TableCell());
                 tr.Cells.Add(new TableCell());
                 tr.Cells[0].Text ="jhjh";
                 tr.Cells[1].Controls.Add(btn);
                 btn.Text = "Remove";
                // btn.ID = "Remove_0";
                 tblName.Rows.Add开发者_如何学运维(tr);
                 PlaceHolder1.Controls.Add(tblName);

Controls added dynamically, must be re-created each time (and prefererably on the Page_Init before the ViewState is parsed)