Convert a file to ASCII

To read from and write to files:



http://support.smartbear.com/viewarticle/55351/



Another option is to use the OLE object:



http://support.smartbear.com/viewarticle/56570/?utm_source=site-search&utm_medium=search-results&utm_campaign=site-search-c&utm_term=working+with+files



Once you are able to open your files you'll need to do the conversion. You can either write some code yourself to do this (I have no idea what you are trying to convert your ASCII file to) or find a library.

How can I know the format of input file : ASCII, UTF, ...?

A few Google searches suggest to me that ADO stream object is the way to go if you are looking to check how a file is encoded and convert it. Not something I have tried myself so can't comment any further. 

There is Smartbear documentation for ADO here:

ADO docs

Also, UTF-encoded files (like files with other type of encoding) usually has a header that can be read if the file is opened as a binary.

http://programmers.stackexchange.com/questions/187169/how-to-detect-the-encoding-of-a-file contains good initial description.

And https://www.google.com.ua/?q=check+if+file+is+utf-8+encoded returns quite a few relevant links.