<form runat="server" id="form1" >
<center>
<strong>List of Applicants</strong>
<br><br>

<asp:DataGrid 
	id="dgOutput" 
	runat="server" 
	AllowSorting="True"
	AutoGenerateColumns="False"
	OnSortCommand="SortColumn"
	CellSpacing="5"
	CellPadding="3"	
	BorderWidth="1px">
	
<Columns>

<asp:TemplateColumn>
	<HeaderTemplate>
		<asp:CheckBox ID="CheckAll" OnClick="javascript: return select_deselectAll(this.checked, this.id);" runat="server"/>
	</HeaderTemplate>	
		 <ItemTemplate>
			 <asp:CheckBox ID="chkSelection" OnClick="javascript: return select_deselectAll(this.checked, this.id);" runat="server" />
		 </ItemTemplate>
 </asp:TemplateColumn>
	
<asp:TemplateColumn SortExpression="login" HeaderText="LoginID">
<ItemTemplate>
<asp:Label ID="lblStudentID"
  Text='<%# DataBinder.Eval(Container.DataItem,"login") %>'
  runat="server" />
</ItemTemplate>
</asp:TemplateColumn>

  
<asp:BoundColumn
  SortExpression="NameFirst"	
  HeaderText="First Name"
  DataField="NameFirst" />
  
<asp:BoundColumn
  SortExpression="NameLast"	
  HeaderText="Last Name"
  DataField="NameLast" />
    
</Columns>	
</asp:DataGrid>
<p>
</p>

<asp:button ID="btnShow" Text="Insert Selected Records" runat="Server"  OnClick="insert_records" />
</center>

<script>
function select_deselectAll (chkVal, idval)
{
	var frm=document.forms[0];
	//Loop through all the items
	for (i=0 ; i<frm.length; i++)
	{
		//Look for the Header Template's Checkbox
			if(idVal.indexof ('CheckAll') != -1)
			{
				//Check if main checkbox is checked, then select or dselect datagrid checkboxes
					if(chkVal==true)
					{
						frm.elements[i].checked=true;
					}
					else
					{
						frm.elements[i].checked = false;
					}				
			}
			else if (idVal.indexOf ('chkSelection') !=-1)
			{
				//Check if any of the checkboxes are not checked, and then uncheck top select all checkbox
				if (frm.elements[i].checked == false)
				{
					frm.elements[1].checked = false; //Uncheck main select all checkbox
				}
			}
	}
}		
		
</script>

</form>