how to pass the checkbox selected gridview rows into another gridview

<table>
        <tr>
            <td>
                <table>
                    <tr>
                        <td>
                            <table>
                                <tr>
                                    <td>
                                        <asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False" CellPadding="3"
                                            GridLines="None" BackColor="White" BorderColor="White" BorderStyle="Ridge" BorderWidth="2px"
                                            CellSpacing="1" onselectedindexchanged="GridView1_SelectedIndexChanged"
                                            AutoGenerateSelectButton="True" >
                                            <Columns>
                                                <asp:TemplateField>
                                                    <ItemTemplate>
                                                        <input type ="checkbox" value="" onclick='addthis(this,<%#Eval("EmpSalary") %>)' />

                                                    </ItemTemplate>
                                                </asp:TemplateField>
                                                <asp:TemplateField>
                                                    <ItemTemplate>
                                                        <%# Eval("EmpName") %>
                                                    </ItemTemplate>
                                                </asp:TemplateField>

                                                <asp:TemplateField HeaderText="Emp Salary">
                                                    <ItemTemplate>
                                                       <%# Eval("EmpSalary") %>
                                                    </ItemTemplate>
                                                </asp:TemplateField>
                                            </Columns>
                                            <FooterStyle BackColor="#C6C3C6" ForeColor="Black" />
                                            <RowStyle BackColor="#DEDFDE" ForeColor="Black" />
                                            <SelectedRowStyle BackColor="#9471DE" Font-Bold="True" ForeColor="White" />
                                            <PagerStyle BackColor="#C6C3C6" ForeColor="Black" HorizontalAlign="Right" />
                                            <HeaderStyle BackColor="#4A3C8C" Font-Bold="True" ForeColor="#E7E7FF" />
                                        </asp:GridView>
                                        <input type="text"  id="resdiv" value="0" />
                                        <asp:HiddenField ID="hidden1" runat="server" />
                                        <asp:Button ID="bbbtbn" runat="server" Width="50px" onclick="bbbtbn_Click" />
                                        <asp:TextBox ID="txt" runat="server"></asp:TextBox>
                                    </td>
                                </tr>
                            </table>

                        </td>
                    </tr>
                </table>
            </td>
        </tr>
    </table>