What file types/extensions would you allow in for a document management application?
<p>I am working on a kinda document management system. The end users are business class users.</p>

<p>I currently check and allow files to be uploaded only if they are one of the followings:</p>

<pre><code>"png|jpe?g|gif|xls|doc|docx|csv|ppt|txt|pdf|rtf"
</code></pre>

<p>my questions are -</p>

<ul>
<li><p>If I add "xml" into the list? can they cause any security issue?</p></li>
<li><p>What other document types/extensions I can add into this?</p></li>
</ul>

<p>Or</p>

<p>Should I check NOT IN <code>"exe|bat|php|js"</code> and allow all other types?</p>

<p>Thanks for suggestions.</p>
