～GridView1中更新数据　CheckBox如何更新

救命啊～～～～～GridView1中更新数据　CheckBox怎么更新
前台代码
<asp:GridView   ID= "GridView1 "   runat= "server "   AllowPaging= "True "   AllowSorting= "True "
                AutoGenerateColumns= "False "   DataKeyNames= "登陆ID "
                GridLines= "None "   PageSize= "20 "   OnRowEditing= "GridView1_RowEditing "   OnRowDeleting= "GridView1_RowDeleting "   OnRowUpdating= "GridView1_RowUpdating "   OnRowCancelingEdit= "GridView1_RowCancelingEdit ">
                <Columns>
                        <asp:BoundField   DataField= "登陆ID "   HeaderText= "登陆ID "   ReadOnly= "True "   />
                        <asp:BoundField   DataField= "姓名 "   HeaderText= "姓名 "   ReadOnly= "True "     />
                        <asp:BoundField   DataField= "电话 "   HeaderText= "电话 "   ReadOnly= "True "     />
                        <asp:BoundField   DataField= "手机 "   HeaderText= "手机 "   ReadOnly= "True "     />
                        <asp:BoundField   DataField= "课程名称 "   HeaderText= "课程名称 "     />
                        <asp:CheckBoxField   DataField= "付款 "   HeaderText= "付款 "     />
                        <asp:CommandField   HeaderText= "编辑 "   ShowEditButton= "True "   />
                        <asp:CommandField   HeaderText= "删除 "   ShowDeleteButton= "True "   />
                </Columns>
                  <RowStyle   BackColor= "#FFFBD6 "   ForeColor= "#333333 "   />
                                                <SelectedRowStyle   BackColor= "#FFCC66 "   Font-Bold= "True "   ForeColor= "Navy "   />
                                                <PagerStyle   BackColor= "#FFCC66 "   ForeColor= "#333333 "   HorizontalAlign= "Center "   />
                                                <HeaderStyle   BackColor= "#990000 "   Font-Bold= "True "   ForeColor= "White "   />
                                                <AlternatingRowStyle   BackColor= "White "   />