How does php achieve clicking a link in a website to jump back to another page and output a specific value?

How does php achieve clicking a link in a website to jump back to another webpage and output a specific value? in my space, there is an index on my own homepage, and a folder d contains a wordpress there are also index files
My webpage a has two links, but in fact the two links point to the same website B (This website is the wordpress homepage) however, I want to click different links and output different values on site B. the following is what I did, but I cannot output it. I don't know how to change it. please help me change it. thank you.
URL a file
Global $ shuchuid;
Echo "link 1



Link 2 ";

Website B files
Global $ shuchuid;
Echo $ _ GET ['shuchuid'];

Reply to discussion (solution)

Echo "link 1



Link 2 ";
Try

Http://www.colg.biz/pinfo.php. look at what I wrote.

Yes. can you ask why? I don't think of the whole website as a Web site. why is it output? 1. I didn't set this website on the website. Why can I read it out? thank you!

Echo "link 1



Link 2 ";
Try

Yes. can you ask why? I don't think of the whole website as a Web site. why is it output? 1. I didn't set this website on the website. Why can I read it out? thank you!

This is the standard for transferring values between URLs and get... I have never seen any quotation marks in URLs.

Your original method of writing a webpage becomes "link 1 ".

It is equivalent to link to B .com, and the custom parameter shuchuid = '1' is not passed.

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Why can I read the homepage?

Not clear

But http:// B .com/in wp can be seen as a http:// B .com/index.php or http:// B .com/index.html is not what you mean

Http:// B .com /? Shuchuid = 1
The meaning of this URL is to link to the http:// B .com/address and pass a parameter shuchuid whose value is 1

Another http:// B .com /? Shuchuid = 1 and http:// B .com? Shuchuid = 1 is different

Http:// B .com /? Shuchuid = 1
The meaning of this URL is to link to the http:// B .com/address and pass a parameter shuchuid whose value is 1

Another http:// B .com /? Shuchuid = 1 and http:// B .com? Shuchuid = 1 is different
What's the difference between the two outputs? thank you.

There is no difference between the two parameters, but the link they direct to (possibly) is different here they direct to the same link...

You don't need to worry about this...

Oh, thank you.