在函数之间共享变量[重复]

Question

我需要根据用户的状态显示不同的措辞。我意识到 while() 变量超出了 Online_Status() 的范围，但我无法弄清楚如何共享变量，甚至无法在 Online_Status() 中定义包含与 while() 相同信息的新变量。我已经尝试将 Online_Status() 放在 while()、while() 附近、while() 之外以及其他所有配置中几个小时。没有发生。我将不胜感激！

<?php

require_once('connect.php');


$con = mysqli_connect(DBHOST, DBUSER, DBPASS, DBNAME) or die('Connection failed: ' . mysqli_connect_error());

$sql = mysqli_query($con, "SELECT UserType, Online, InChat FROM membership WHERE UserType = 2 ORDER BY Online DESC");


    while($row = mysqli_fetch_array($sql)){

    $UserType = $row['UserType'];
    $Online = $row['Online'];
    $InChat = $row['InChat'];


    echo Online_Status(); 


    }

    function Online_Status(){ 

        if ($Online == 0) {
            echo "I am not online. Please come back later";
        }

        else if($Online == 1 && $InChat == 0){
            echo "I am Online and I will be in my chatroom shortly.";
        }

        else if($Online == 1 && $InChat == 1){
            echo "I am Online chat with me now!";
        }

}

mysqli_close($con);
?> 

Answer 1

使用global关键字：

function Online_Status(){ 
    global $Online;
    if ($Online == 0) {
        echo "I am not online. Please come back later";
    }

}

最好通过函数参数通过函数传递变量：

function Online_Status($Online){ 
    if ($Online == 0) {
        echo "I am not online. Please come back later";
    }
}

并称它为：

Online_Status($Online);

另外，看看PHP 的Variable Scope。