Hi how can i export below gridviews to excel
<asp:GridView ID="gridpurchase" AutoGenerateColumns="False" runat="server" DataKeyNames="Purchase_ID" OnRowDataBound="OnRowDataBound" CssClass="table table-bordered text-nowrap">
<Columns>
<asp:TemplateField HeaderText="Preview">
<ItemTemplate>
<img alt="" style="cursor: pointer" src="../Images/plus.png" />
<asp:Panel ID="pnlproducts" runat="server" Style="display: none">
<asp:GridView ID="gvProducts" runat="server" AutoGenerateColumns="false" CssClass="table table-bordered">
<Columns>
...
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