How I Sum column values using Jquery (aspx)

Hi Friends, 

I tried, but I can't get column sum values, and the individual column values show in grid fooder, and overall grant total values show label lbl_grtot, pls help me. 

This is my grid-view 

<asp:GridView ID="Grv_ProjectBooking" runat="server" AutoGenerateColumns="False" CellPadding="4" CssClass="smalltext2" ForeColor="#333333" GridLines="Vertical" OnRowDeleting="Grv_Project_RowDeleting" Width="647px" ShowFooter="True"><AlternatingRowStyle BackColor="White" ForeColor="#284775" /><Columns><asp:BoundField DataField="RowNumber" HeaderText="SNo" /><asp:TemplateField HeaderText="Pillar"><ItemTemplate><asp:DropDownList ID="Drd_Pillar" runat="server" AutoPostBack="true" CssClass="normalText2" onselectedindexchanged="GetProject_Names"><asp:ListItem Value="0">Select</asp:ListItem><asp:ListItem Value="1">CLEP</asp:ListItem><asp:ListItem Value="2">SHG</asp:ListItem><asp:ListItem Value="3">SDTC</asp:ListItem></asp:DropDownList></ItemTemplate></asp:TemplateField><asp:TemplateField HeaderText="Project Booking"><FooterTemplate><asp:Label ID="Label150" runat="server" CssClass="tablehead2" ForeColor="White" Text="Total :"></asp:Label></FooterTemplate><ItemTemplate><asp:DropDownList ID="Drd_ProjectCostCtr" runat="server" AutoPostBack="true" CssClass="normalText2" Width="180px"><asp:ListItem Value="0">Select One</asp:ListItem></asp:DropDownList></ItemTemplate></asp:TemplateField><asp:TemplateField HeaderText="Gr.Sal"><FooterTemplate><asp:Label ID="lbl_tot_grsal" runat="server"  CssClass="tablehead2" ForeColor="White"></asp:Label></FooterTemplate><ItemTemplate><asp:TextBox ID="Txt_GrSalary" runat="server" CssClass="normalText2" onblur="GetTotal(this)" autocomplete="off"  MaxLength="7" onkeypress="return isNumberKey(event)" Width="50px"></asp:TextBox></ItemTemplate></asp:TemplateField><asp:TemplateField HeaderText="MobPh"><FooterTemplate><asp:Label ID="lbl_tot_moballow" runat="server" CssClass="tablehead2" ForeColor="White"></asp:Label></FooterTemplate><ItemTemplate><asp:TextBox ID="Txt_MobAllow" runat="server" CssClass="normalText2"  onblur="GetTotal(this)" MaxLength="7" onkeypress="return isNumberKey(event)" Width="50px"></asp:TextBox></ItemTemplate></asp:TemplateField><asp:TemplateField HeaderText="Loc.TA"><FooterTemplate><asp:Label ID="lbl_tot_ta" runat="server" CssClass="tablehead2" ForeColor="White"></asp:Label></FooterTemplate><ItemTemplate><asp:TextBox ID="Txt_LocTA" runat="server" CssClass="normalText2" MaxLength="7" onblur="GetTotal(this)" onkeypress="return isNumberKey(event)" Width="50px"></asp:TextBox></ItemTemplate></asp:TemplateField><asp:TemplateField HeaderText="Hardship"><FooterTemplate><asp:Label ID="lbl_tot_hsip" runat="server" CssClass="tablehead2" ForeColor="White"></asp:Label></FooterTemplate><ItemTemplate><asp:TextBox ID="Txt_HardShip" runat="server" CssClass="normalText2" MaxLength="7" onblur="GetTotal(this)" onkeypress="return isNumberKey(event)" Width="50px"></asp:TextBox></ItemTemplate></asp:TemplateField><asp:TemplateField HeaderText="+"><ItemTemplate><asp:ImageButton ID="ImgBtn_Prj_Yes" runat="server" CausesValidation="false" Height="21px" ImageUrl="~/Images/smallsuccess.gif" onclick="Project_Grid_AddtlRow" Width="21px" /></ItemTemplate></asp:TemplateField><asp:CommandField ButtonType="Image" DeleteImageUrl="~/Images/Med_smallfail.gif" HeaderText="-" ItemStyle-CssClass="smalltext" ShowDeleteButton="True"><ItemStyle CssClass="smalltext" /></asp:CommandField></Columns><EditRowStyle BackColor="#999999" /><FooterStyle BackColor="#5D7B9D" Font-Bold="True" ForeColor="White" /><HeaderStyle BackColor="#5D7B9D" Font-Bold="True" ForeColor="White" /><PagerStyle BackColor="#284775" ForeColor="White" HorizontalAlign="Center" /><RowStyle BackColor="#F7F6F3" ForeColor="#333333" /><SelectedRowStyle BackColor="#E2DED6" Font-Bold="True" ForeColor="#333333" /><SortedAscendingCellStyle BackColor="#E9E7E2" /><SortedAscendingHeaderStyle BackColor="#506C8C" /><SortedDescendingCellStyle BackColor="#FFFDF8" /><SortedDescendingHeaderStyle BackColor="#6F8DAE" /></asp:GridView>

This is my Jquery, here am getting result zero, and loop is not ending 

<script src="JScript/jquery-1.5.2.js" type="text/javascript"></script>
<script type="text/javascript">

function GetTotal() {
               var gr_tot = 0;

               var t_grsal = 0;
               var t_mobph = 0;
               var t_locta = 0;
               var t_hrshp = 0;


               var grid = document.getElementById("Grv_ProjectBooking");
               if (grid.rows.length > 0) {
                   var inputs = grid.getElementsByTagName("input");
                   var i = 0;
                   var rx = 2;
                   i = (rx + i);

                   var grl = (grid.rows.length - 1);
                   for (var r = 1; r < grl; r++) {
                       if (inputs[i].name.indexOf("Txt_GrSalary") > 0) {
                           if (inputs[i].value != "") {
                               gr_tot = gr_tot + parseInt(inputs[i].value);
                               t_grsal = parseInt(inputs[i].value);
                           }
                       }
                       rx = (rx + 1);
                       i = (rx);

                       if (inputs[i].name.indexOf("Txt_MobAllow") > 1) {
                           if (inputs[i].value != "") {
                               t_mobph = parseInt(inputs[i].value);
                           }
                       }
                       rx = (rx + 1);
                       i = (rx);

                       if (inputs[i].name.indexOf("Txt_LocTA") > 1) {
                           if (inputs[i].value != "") {
                               t_locta = parseInt(inputs[i].value);
                           }
                       }

                       rx = (rx + 1);
                       i = (rx);

                       if (inputs[i].name.indexOf("Txt_HardShip") > 1) {
                           if (inputs[i].value != "") {
                               t_hrshp = parseInt(inputs[i].value);
                           }
                       }

                       rx = (rx + 1);
                       i = (rx);$("[id*=lbl_tot_grsal]").html(t_grsal.toString());$("[id*=lbl_tot_ta]").html(t_mobph.toString());  $("[id*=lbl_tot_moballow]").html(t_locta.toString());$("[id*=lbl_tot_hsip]").html(t_hrshp.toString());

                       gr_tot = (t_grsal + t_mobph + t_locta + t_hrshp);$("[id*=lbl_grtot]").html(gr_tot.toString());

                       gr_tot = 0;

                       rx = (rx + 2);
                       i = 0;
                       i = (rx);
                   }
               }
           }
</script>

Thanks in advance