You are creating a PHP website on Windows Azure and need to install additional PHP extensions not provided by default (like MongoDB or IonCube), you’ve come to the right post. It is quite easy.
I’m going to demo this with 2 extensions; MongoDB and IonCube. The first is a regular PHP extension, and the second one is a Zend extension.
It is important that you download the 32-bit version of the DLLs (unless you are using a Standard website instance and specified that it runs on 64-bit), and also download the Non Thread Safe versions (if provided).