dynamically adding checkboxcolumn when datagridview add rows

Your question is not so clear. In spite of that whatever I understood from your question is (If I am not wrong) you want to add DataGridViewCheckBoxColumn to your DataGrid dynamically.
Try this to add DataGridViewCheckBoxColumn dynamically in your datagridview.

DataGridViewCheckBoxColumn chk = new DataGridViewCheckBoxColumn();
dataGridView1.Columns.Add(chk);
chk.HeaderText = "Check Data";
chk.Name = "chk";

--Amit