我不会停止它，而是在没有许可证的情况下显示一些消息。

I will go not with stop it, but to show some message if you do not have license.

这是一个示例，一个想法。

This is an example, and an idea.

您可以在 global.asax上使用此代码。 如果您在开始时没有许可证，请打开一个标志，然后再不允许显示任何页面，然后发送可以保留html文件的页面。

You can use this code on global.asax where if you do not have licenses the moment you start, you open a flag, and after that you do not allow any page to show, and you send a page that you can keep on an html file.

private static bool fGotLicense = true;

protected void Application_Start()
{
    try
    {
        MyApp.cNumberOfLicenses = COM.GetNumberOfLicenses();
    }
    catch(Exception e)
    {
        // log exception
        // stop web site.
        fGotLicense = false;
    }
}

protected void Application_BeginRequest(Object sender, EventArgs e)
{
    HttpApplication app = (HttpApplication)sender;

    // if not have license - let show some infos
    if (!fGotLicens)
    {
        // the file we look now is the app_offline_alt.htm
        string cOffLineFile = HttpRuntime.AppDomainAppPath + "app_offline_alt.htm";

        // if exist on root
        if (System.IO.File.Exists(cOffLineFile))
        {
            using (var fp = System.IO.File.OpenText(cOffLineFile))
            {
                // read it and send it to the browser
                app.Response.Write(fp.ReadToEnd());
                fp.Close();
            }    
        }

       // and stop the rest of processing
       app.Response.End();
       return;
    }
}