Word count of an uploaded document??

Question

Hello -

I am beginner and learning asp.net and C#.

I am trying to develop an web application which has to count the number of words in an uploaded document using file upload control.

Type of files it should allow to upload are word,excel,powerpoint,pdf,rtf and txt.

For example if i upload a word document it should save in a default location on server, latter should show me the number of words available in that document.

I am using Visual Web Developer 2005/2008.

Please help me how to do this application.

Thank you.