WordPress网址参数不起作用

Question

What I am trying to do right now is really simple. I want to send a parameter through the URL and then display it on a WordPress page. This is what I am currently doing:

The URL I am putting in is www.domain.com/signin_page?message=yo

The shortcode I added to my functions.php file is:

function write_login_message( $atts) {
  return "Message: " . $_GET['message'];
};
add_shortcode( 'write_message', 'write_login_message' );

The result is "Message: ". Also, I get a notice: Undefined index: message in [...] . I tried something I found in a discussion (making a plugin that sets a query variable) but that didn't work and now I'm stuck. I'd appreciate any help.

UPDATE: $_GET['message'] works on my production server. It isn't working in my test/sandbox server (they are basically the same thing though). This narrows it down, but I am still not certain what the cause is. I can at least move on knowing that I can get it to work on my production server though.

Answer 1

Use this function to create the URL:

add_query_arg( array(
    'key1' => 'value1',
    'key2' => 'value2',
), 'http://example.com' );

• https://developer.wordpress.org/reference/functions/add_query_arg/

Answer 2

Hello you are creating short code and in the short code the parameters we need to define with the short code and you want to get it from url that is not possible as you are doing.Shortcode variables are passing like that

[write_message message="yo"] and if you want to get it directly from URL then use $_GET['message']