PHP內插變量作爲函數參數

Question

不知道這是否是一個WordPress問題，但我不這麼認爲。

我有一個while循環，我遍歷用戶創建的內容循環，試圖獲得一個元字段，它具有與當前「鍵」相匹配的數字標識符（如果可以稱之爲，因爲這根本不是數組，所以用戶可以使用一些前端參數創建自定義循環。$this_label_url通過插值方式請求人造「鑰匙」$this_label_url = get_post_meta($post->ID, 'instructor_{$number}_label_url', true);。在這種情況下，變量插補不可能嗎？

<?php 
    $total_panels = get_post_meta($post->ID, 'total_panels', true); // set by the user with a custom meta value called "total_panels" (an integer) 
    $count = 1; // just a fake "key" for looping through my `while` 

    // create a faux "number" - simply takes $count and adds leading zero if not present 
    while ($total_panels >= $count) : 

    if ($count >= 9) { 
     $number = '0' . $count; 
    } else { 
     $number = $count; 
    } 
$this_label_url = get_post_meta($post->ID, 'instructor_{$number}_label_url', true); // returns as an empty string, 

Answer 1

這是可能的，但你需要使用雙引號;單引號不會被分析插值

$this_label_url = get_post_meta($post->ID, "instructor_{$number}_label_url", true);