GridView导出到excel - Control 'ctl00_ServerContent_GridView1' of type 'GridView' must be placed inside a form tag with runat=server.

将GridView导出到excel 时报错

Control 'ctl00_ServerContent_GridView1' of type 'GridView' must be placed inside a form tag with runat=server.

解决方法：

在CS代码中添加如下方法：

    public override void VerifyRenderingInServerForm(Control control)
    {
    }