Check Uncheck CheckBoxes on CheckBox selected inside DataGrid header using JavaScript in ASP.Net

seriverma says:

In datagrid I have two column “Approve All” and “Reject All”,and datagrid bind on run time.

How my code works:

1)  When I clicked select all checkbox all checkbox display checked and Reject all colunm display unchecked but header column of reject all not unchecked please help 

WHAT I want:-

2)  When I clicked select all checkbox all checkbox display checked and Reject all colunm display unchecked

using below set of code:

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<script language="javascript">                          function dgSelectAllorUnselectAll(grdid,obj,objlist)             {                 //this function decides whether to check or uncheck all                                   if(obj.checked)                     DGSelectAll(grdid,objlist)                 else                     DGUnselectAll(grdid,objlist)             }                            function DGSelectAll(grdid,objid)             {                 //this function is to check all the items                 var chkbox;                 var i=2;                 chkbox=document.getElementById(grdid + '__ctl' + i + '_' + objid);                 while(chkbox!=null)                 {                     chkbox.checked=true;                     i=i+1;                     chkbox=document.getElementById(grdid + '__ctl' + i + '_' + objid);                                       }             }               function DGUnselectAll(grdid,objid)             {                 //this function is to uncheckcheck all the items                 var chkbox;                 var i=2;                   chkbox=document.getElementById(grdid + '__ctl' + i + '_' + objid);                 while(chkbox!=null)                 {                     chkbox.checked=false;                     i=i+1;                     chkbox=document.getElementById(grdid + '__ctl' + i + '_' + objid);                 }             }                       </script> <asp:datagrid id="dg_Business_Tour" runat="server" CssClass="ThinTableLeft" AutoGenerateColumns="False" >                                     <SelectedItemStyle Wrap="False"></SelectedItemStyle>                                 <ItemStyle Wrap="False"></ItemStyle>                                 <HeaderStyle Font-Size="7pt" Font-Names="Verdana" Font-Bold="True" Wrap="False" CssClass="CellTop"></HeaderStyle>                                 <Columns>                                                                                                                 <asp:TemplateColumn HeaderText="Select" HeaderStyle-Width="7%" >                                         <HeaderTemplate>                                             <input id="chkAll" type="checkbox" onclick="dgSelectAllorUnselectAll('dg_Business_Tour',this,'chkClicked')">Select                                             All                                         </HeaderTemplate>                                         <ItemTemplate>                                             <asp:CheckBox ID="chkClicked" onclick="javascript:calculateTotal(this,'dg_Business_Tour','chkReject')" Runat="server"></asp:CheckBox>                                         </ItemTemplate>                                     </asp:TemplateColumn>                                                                                                           <asp:TemplateColumn HeaderText="Reject" HeaderStyle-Width="6%" >                                     <HeaderTemplate>                                             <input id="chkRejAll" type="checkbox" onclick="dgSelectAllorUnselectAll('dg_Business_Tour',this,'chkReject')" />Reject all                                                                                       </HeaderTemplate>                                         <ItemTemplate>                                             <asp:CheckBox ID="chkReject" onclick="javascript:calculateTotal(this,'dg_Business_Tour','chkClicked')" Runat="server" ></asp:CheckBox>                                         </ItemTemplate>                                     </asp:TemplateColumn>                                                                                                                                                                                   </Columns>                             </asp:datagrid>

 

<script language="javascript">
    function dgSelectAllorUnselectAll(grdid, obj, objlist) {
        //this function decides whether to check or uncheck all

        if (obj.checked)
            DGSelectAll(grdid, objlist)
        else
            DGUnselectAll(grdid, objlist)
    }

    function DGSelectAll(grdid, objid) {
        //this function is to check all the items

        var chkbox;
        var i = 2;
        chkbox = document.getElementById(grdid + '__ctl' + i + '_' + objid);
        while (chkbox != null) {
            chkbox.checked = true;
            i = i + 1;
            chkbox = document.getElementById(grdid + '__ctl' + i + '_' + objid);

        }
        if (objid == 'chkReject') {
            DGUnselectAll(grdid, 'chkClicked', 'chkAll')
        }
        else {
            DGUnselectAll(grdid, 'chkReject', 'chkRejAll')

        }
    }

    function DGUnselectAll(grdid, objid, Header) {
        //this function is to uncheckcheck all the items
        var chkbox;
        var i = 2;
        chkbox = document.getElementById(grdid + '__ctl' + i + '_' + objid);

        while (chkbox != null) {
            chkbox.checked = false;
            i = i + 1;
            chkbox = document.getElementById(grdid + '__ctl' + i + '_' + objid);
        }
        var chkbox1;
        chkbox1 = document.getElementById(Header);
        chkbox1.checked = false
    }

</script>