Grid on row Edit and Update ...

protected void GridViewEmpAttendance_RowEditing(object sender, GridViewEditEventArgs e)
        {
            GridViewEmpAttendance.EditIndex = e.NewEditIndex;
            SendEmpAndCenterToGetAttendance(dpd_CenterName.SelectedItem.Text.ToString(), dpd_emp.SelectedItem.Text.ToString());
        }

        protected void GridViewEmpAttendance_RowCancelingEdit(object sender, GridViewCancelEditEventArgs e)
        {
            GridViewEmpAttendance.EditIndex = -1;
            SendEmpAndCenterToGetAttendance(dpd_CenterName.SelectedItem.Text.ToString(), dpd_emp.SelectedItem.Text.ToString());
        }

        protected void GridViewEmpAttendance_RowUpdating(object sender, GridViewUpdateEventArgs e)
        {
            Label _ecode = (Label)GridViewEmpAttendance.Rows[e.RowIndex].FindControl("lbl_ecode");
            Label _Date = (Label)GridViewEmpAttendance.Rows[e.RowIndex].FindControl("lbl_date");
            DropDownList _EmpStatus = (DropDownList)GridViewEmpAttendance.Rows[e.RowIndex].FindControl("DStatusEdit");
            string ecode = _ecode.Text.ToString();
            string status = _EmpStatus.SelectedValue.ToString();
            string dat = _Date.Text.ToString();
            MtdUpdateAttendance(ecode, dat, status);
            GridViewEmpAttendance.EditIndex = -1;
            SendEmpAndCenterToGetAttendance(dpd_CenterName.SelectedItem.Text.ToString(), dpd_emp.SelectedItem.Text.ToString());
        }

        protected void GridViewEmpAttendance_RowDataBound(object sender, GridViewRowEventArgs e)
        {
            if (e.Row.RowType == DataControlRowType.DataRow && (e.Row.RowState & DataControlRowState.Edit) == DataControlRowState.Edit)
            {
                DropDownList DDLStatus = (DropDownList)e.Row.FindControl("DStatusEdit");
                DDLStatus.DataSource = StatusBind();
                DDLStatus.DataTextField = "Status";
                DDLStatus.DataValueField = "Status";
                DDLStatus.DataBind();
                DDLStatus.Items.Insert(0, new ListItem("Select", "0"));
                DDLStatus.SelectedValue = Convert.ToString(GridViewEmpAttendance.DataKeys[e.Row.RowIndex]["status"].ToString());
            }
        }