How to rewrite this ASP code in PHP?

Question

PHP

There is an ASP project consisting of:
1. asax file

public class MyImage : System.Web.HttpApplication
{
    /* поля класса */

    protected void Application_Start(object sender, EventArgs e)
    {
        /* код */
    }
}

2.ashx file

public class GetImage : IHttpHandler
{
    public void ProcessRequest(HttpContext context)
    {
        /* код генерации изображения img*/

        context.Response.ContentType = "image/png";
        context.Response.BinaryWrite(img);
    }

    public bool IsReusable
    {
        get
        {
            return false;
        }
    }
}

When accessing GetImage.ashx, the web server returns the image. How to rewrite only ashx in PHP I understand

<?PHP
/* код генерации изображения img*/

header('Content-type: image/png');
imagepng($img);
imagedestroy($img);
?>

But I also need a part in asax. How to implement it in PHP?

Answer 1

And it doesn't need to be rewritten. This is part of the initialization of an ASP application and is very dependent on the IIS server.