GridView中的按钮的OnClick事件无法正常工作

Here is my DataGridView

这是我的DataGridView

<asp:GridView ID="gvPredstave" runat="server" CssClass="gridview" 
        AlternatingRowStyle-CssClass="even" AutoGenerateColumns="True">
        <Columns>
            <asp:TemplateField>
                <ItemTemplate>
                    <asp:Button ID="btnRezervisi" runat="server" Text="Rezervisi" onclick="Button1_Click" />
                </ItemTemplate>
            </asp:TemplateField>
        </Columns>
    </asp:GridView>
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