how to match values of two columns on databindingcomplete event. and if all the records of both the columns match disable gridview

Please help me

i have a code for this but this can be done only on cell content click

 if (e.ColumnIndex == 4)
            {
                if (Double.Parse(dataGridView1.Rows[e.RowIndex].Cells[3].Value.ToString()) == Double.Parse(dataGridView1.Rows[e.RowIndex].Cells[4].Value.ToString()))
                {
                    MessageBox.Show("Records matched");

                    dataGridView1.CurrentRow.ReadOnly = true;
                    dataGridView1.CurrentRow.DefaultCellStyle.BackColor = Color.LightGray;

                }
                else
                {
                    MessageBox.Show("Records does not match");
                }
            }

this code is perfect but it cant be fired on databindingcomplete. Pls help