Question

The only way that I’ve been able to test whether or not the application is being built with aspnet_compiler is with the following:

HttpRuntime.AppDomainAppId.EndsWith("_precompile")

However, this feels like a hack. I could check against the metabase path, however that can easily be changed with a switch to the executable. Is there a more robust, documented way to determine this?

Answer 1

Here is what I’ve come up with (though it’s still quite dirty). If a better answer is provided, I change it to the accepted answer.

public static bool IsPerformingPrecompilation()
{
    var simpleApplicationHost = Assembly.GetAssembly(typeof(HostingEnvironment))
                                    .GetType("System.Web.Hosting.SimpleApplicationHost", throwOnError: true, ignoreCase: true);

    return HostingEnvironment.InClientBuildManager && 
           HostingEnvironment.ApplicationID.EndsWith("_precompile", StringComparison.InvariantCultureIgnoreCase) && 
           HostingEnvironment.ApplicationHost.GetType() == simpleApplicationHost;
}