php - If 语句有效，而 Else 语句无效

Question

<?php
  // Check connection

     $servername = "localhost";
     $username = "root";
     $password = "1234";
     $dbname = "project";

     htmlspecialchars($a = $row1['stno']);

     $d1 = $row7['userID'];

       // Create connection
               $conn = new mysqli($servername, $username, $password, $dbname);
       // Check connection
                if ($conn->connect_error) {
                     die("Connection failed: " . $conn->connect_error);
                } 

                $sql = "SELECT * FROM likes WHERE rec = $a";
                $result = $conn->query($sql);

                if ($result->num_rows > 0) {
                    // output data of each row
                    while($row = $result->fetch_assoc()) {
                         $z4 = $row['do'];
                         if ($d1 == $z4)
                         {
                             include ("unlikee.php");
                         }
                         else {
                             include ("likee.php");
                         }
                    }
                } 
                $conn->close();
       ?>

这是一个与我的 sql 连接的 Like 按钮，一切正常，但问题出在 Else 语句

            else 
        include ("likee.php");

它不起作用，而 if 语句起作用。逻辑 is Likee.php 包含 Likee.php 包含的脚本，反之亦然，并且每当它们是已放置的“喜欢”时，就会显示“喜欢”按钮，但每当它们不是“喜欢”时，“喜欢”按钮是不可见的

Answer 1

你说“只要没有喜欢，喜欢按钮就看不见”。这是因为当没有“喜欢”时，您永远不会执行包含“喜欢”或“不喜欢”按钮的代码部分

if ($result->num_rows > 0) {

更新了代码段。当结果行数为0时，执行else以包含likee.php

if ($result->num_rows > 0) {
// output data of each row
while($row = $result->fetch_assoc()) {

    $z4 = $row['do'];
    if ($d1 == $z4) {
          include ("unlikee.php");
    } 
} else {
    include ("likee.php");
}