Call javascript funcation sharepoint Grid View.

<asp:templatefield HeaderText="Approve">
HeaderStyle CssClass="ms-vh2" Font-Bold="True" />
<ItemStyle CssClass="ms-vb2" />
<ItemTemplate>
<asp:HyperLink ID="hplink" runat="server" NavigateUrl='<%# Eval("ID", "javascript:getEditPM({0})") %>'>Approve</asp:HyperLink>
</ItemTemplate>
</asp:templatefield>