1. When two different files are uploaded with one name then its overwrite the previous file
This should not be surprising, unless the API specifically checks for the existence of a file with the same name.
2. Can I change the name of uploaded file before saving on the server
Without a link to the API documentation it's difficult to know. That said, five seconds on Google led me to
this.
3. I just want to upload zip or rar format. Can I handle this with Orielly API?
Automatically? Sure doesn't look like it: can't you just check the name of the FilePart's file?
4. Any solution to check virus before loading to server?
Not in the API itself; it's a multipart request parser, not an antivirus solution.
