Dynamically added Checked Changed Event is not Firing

// binding datatable Dynamically..
protected void ddlRole_SelectedIndexChanged(object sender, EventArgs e)
{


        for (int i = 0; i < DtOperation.Rows.Count; i++)
        {
            Dt.Columns.Add(DtOperation.Rows[i][0].ToString());
        }
        dgrDynamic.DataSource = Dt;
        dgrDynamic.DataBind();
.
.
        //addind check boxes dynamically.

        tcCheckCell = new TableCell();
        var checkBox = new CheckBox();

       // ActivityID|OperationID is stored to work it at the time of Save in CheckedChanged.

       checkBox.ID = DtOperation.Rows[i][0] + "|" + DtOperation.Rows[i][2];
       checkBox.AutoPostBack = true;
       checkBox.Checked = true;
       checkBox.CheckedChanged +=new EventHandler(checkBox_CheckedChanged);

        tcCheckCell.Controls.Add(checkBox);
                                        dgrDynamic.Rows[j].Cells.RemoveAt(GetColumnIndexByName((int)DtOperation.Rows[i][2]));
                    dgrDynamic.Rows[j].Cells.AddAt(GetColumnIndexByName((int)DtOperation.Rows[i][2]), tcCheckCell);
                    //(int)DtOperation.Rows[i][2]+2
}


void checkBox_CheckedChanged(object sender, EventArgs e)
{

...Code;
}