Get MetaData information about a file during file uploading

Question

hi..

how to Get MetaData information about a file during file uploading in asp.net?

metadata info. like date created, date modified,size. i.e) right click the file and goto details , it show the information about the file. i need those information.

i have a pdf URL , (for ex. http://www.ex.com/sample.pdf) i downloaded the url and save it inot my server. now another user adding the same url, here i need to check the url's metadata information , if the url is modified then i need to download the url and save it to my server.

so that only i need to take the metadata information of a file and a file url.

how to achieve this..

need ur suggestions with examples..


Note:
i have attached the sample file details which i need take from a file or a http file url.

regards
gopal.s