create a temp file with system created name

define system created name? and how are you going to create it? batch file, script, visual studio?

And at which time (or other criteria) it should get disposed?

Here's what I want to do: create a PDF and allow the browser to display it.  But I'm trying to avoid worrying about deleting the PDF.  if the user does not print it, I want to delete it.   Or better yet display an in-memory PDF in a browser window.

and you are creating a pdf of WHAT that has to be a temporary file?

When you say display in a browser do you mean using iis to display a webpage? do you want to use adoboe distiller to make the pdf? you need to be a lot more forthcoming in describing exactly what you want to do and where you are having a problem

"display an in-memory PDF in a browser window"
A file open in a browser is not "in memory", it is downloaded from its source location to the current user's temporary browser cache.  Depending on the browser's settings, it may or may not be deleted when the browser closes.

There are too many missing elements to guess what you are trying to achieve.  It sounds like you are trying to show a "Print Invoice" function like you get when you buy something on eBay through PayPal, except create a PDF file instead.

I using a product called Aspose to create a PDF - a file.   I can point to a URL to where the file was created and display that file in a browser window.  I can then print the PDF.    This works fine.  I'm trying to eliminate the creation of the PDF file.  This is for internal company use only, so I have control over where the file gets created and then the corresponding URL.  

Do this make sense?  

you can't display what does not exist.. why can't you just use a regular webform?

How do I display a PDF using a WEB form?

You're not understanding what I meant.. you have data that you are creating a pdf with my question was why don't you just display the data in a webform (webpage)

or does this pdf already exist as a static document on your website that you want to display to the user? and you want to know how to display it?
<iframe src="http://docs.google.com/gview?url=http://example.com/mypdf.pdf&embedded=true" style="width:718px; height:700px;" frameborder="0"></iframe>

Only was a partial solution for me.

a link would be nice..