No, open source only and it must be GPL (or compatible) licensed. I highly recommend you read the Plugin Developer Guidelines, especially #4.
4. Code must be (mostly) human readable.
Obscuring code by hiding it with techniques or systems similar to p,a,c,k,e,r‘s obfuscate feature, uglify’s mangle, or unclear naming conventions such as $z12sdf813d, is not permitted in the directory. Making code non-human readable forces future developers to face an unnecessary hurdle, as well as being a common vector for hidden, malicious code.
We require developers to provide public, maintained access to their source code and any build tools in one of the following ways:
- Include the source code in the deployed plugin
- A link in the readme to the development location
We strongly recommend you document how any development tools are to be used.
Moved to Everything else WordPress, this is not an Developing with WordPress topic.
I want to know can I encode the PHP files with ioncube and upload in WordPress directory ?
No, you can’t.