Javascript-php uses xpath to get the variable value declared in the script on the page?

How does php use xpath to get the variable value declared in the script on the page? {Code...}. for example, if a webpage contains the preceding content, can I retrieve the message value? It is not cost-effective for me to retrieve the message from the entire html segment ...... How does php use xpath to get the variable value declared in the script on the page?

Script var message = 'This is the text to be catch... '; script

For example, if a webpage contains the preceding content and I want to obtain the value of the message, how can this problem be solved?

It is not cost-effective for me to retrieve the message from the entire html segment ......

Reply content:

How does php use xpath to get the variable value declared in the script on the page?

Script var message = 'This is the text to be catch... '; script

For example, if a webpage contains the preceding content and I want to obtain the value of the message, how can this problem be solved?

It is not cost-effective for me to retrieve the message from the entire html segment ......

Isn't it realistic that you can only load a part of a page? at any time, you need to obtain the page completely first. if you don't want to use regular expressions to retrieve the page completely, you can consider using a php library similar to jquery
Https://github.com/tburry/pquery