please paste the following code in your java script area
function CheckAllDataViewCheckBoxes( checkVal)
{ for(i = 0; i < document.forms[0].elements.length; i++)
{elm = document.forms[0].elements[i]if (elm.type == ‘checkbox’)
{
{elm.checked = checkVal }
}
}
}
and following line on the header for ur check boxes field in item tamplate of grid view
<input id=’chkAllItems’ type=’checkbox’ onclick=’CheckAllDataGridCheckBoxes(document.forms[0].chkAllItems.checked)’ />
all sample Grid View code is here
<asp:GridView ID=”grdMembers” AllowPaging=”true” AllowSorting=”true” runat=”server” Width=”100%” AutoGenerateColumns=”False” OnRowDataBound=”grdMembers_RowDataBound” CellPadding=”3″ >
<HeaderStyle Height=”25px” ></HeaderStyle>
<Columns>
<asp:TemplateField ItemStyle-HorizontalAlign=”Center” headerText=”<input id=’chkAllItems’ type=’checkbox’ onclick=’CheckAllDataViewCheckBoxes(document.forms[0].chkAllItems.checked)’ />” >
<ItemTemplate>
<input id=”RowSelectorUser” runat=”server” name=”RowSelectorUser” type=checkbox value='<%# Eval(“ItemId”) %>’ />
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
on run time when u click check box on gridview all check boxes checked or unchecked with it