有一个按钮，我想调用一个PHP函数以及一个javascript函数？

I have a file, where i use a button, called MP4 Quality, When i click on that button, it opens a pop-up and ask for another button to press, to download the video, There is javascript with first button, and when it clicks, open the pop-up and give the second button, from where PHP is used, now i want it to download on single click, I have a file, where i use a button, called MP4