How to use JavaScript to enable ifram to access each other and communicate with PHP?

This article mainly introduces the example of using JavaScript to enable ifram to access each other and communicate with PHP. It also provides a detailed demonstration of the access between the same domain. For more information, see Mutual access between iframe and the main framework

1. Mutual access between the same domain

Assume that both a.html and B .html domain are localhost (same domain)
In A.html, iframe is embedded into B .html, name = myframe
A.html has js function fMain ()
B .html has js function named rame ()
A.html needs to be implemented to call B .html's javasrame(example, B .html calls A.html's fMain ()

A.html

     
   Main window