通过其他站点在全局功能中打印消息

I have something like this:

<?php
function send_pm(){
    $text = "print this text on screen";
}   

if(function_exists('send_pm')){
    send_pm();

    global $text;

    echo $text;
}

?>

My intention, is to show the message within send_pm, using its own array, already defined on the function. As you see, if you actually execute this script, it will return nothing. I don't understand why this is happening, because I already defined the $text var.

Thank you guys.

Adjust your send_pm() function to:

function send_pm(){
    global $text;
    $text = "print this text on screen";
}

That said, I highly recommend against global variables as it isn't the best or safest way to do things.

If I correctly understood your requirements, you can try something like this instead:

function send_pm($msg_id) {
    $messages = array(
       'msg1' => 'print this text on screen',
       'msg2' => 'print this other text on screen',
       'msg3' => 'etc',
    );

    return $messages[$msg_id];
}

if (function_exists('send_pm')) {
    echo send_pm('msg1');
}