<a href="javascript:;" class="layui-btn" onclick="reportExcel()">导出Excel</i></a>
<form id="form1" runat="server">
            <asp:Button ID="Button1" runat="server" Text="Button" OnClick="Button1_Click"  />
</form>

protected void Button1_Click(object sender, EventArgs e)
        {
            //随便写
                Response.Write("hellow wordl");
        }

function reportExcel() {
        $("#<%=Button1.ClientID%>").click();
    }