为什么我的一些 html 内容在添加一些 php 代码后被删除？

Question

添加一些 PHP 代码后，下面的代码将被删除。如果我删除 PHP 部分，那么它工作正常。即使在源代码中，下面的 HTML 代码也没有显示

    <div class="row data">
                    <div class="row info">
                        <div class="datatitle">Education</div>
                    </div>

                    <div class="grad-fetch row">
                        <?php
        session_start();
        $hostname = "127.0.0.1";
        $username = "root";
        $db_password = "";
        $db_name = "resume";

        $conn = mysqli_connect($hostname, $username, $db_password, $db_name);
        if(!$conn){
            die("connection failed : ".mysqli_connect_error());
        }

       /* $sql =  graduation(degree_status ,college ,start_year ,end_year ,degree ,stream ,performence_scale ,performence_marks)*/


        $sql = 'SELECT * FROM graduation ';

        $result = mysqli_query($conn, $sql);
        if (!$result) {
            die("Error: " . $sql . "<br>" . mysqli_error($conn));
        }  
        while ($row=mysqli_fetch_array($result)) {
            $deg= $row['degree'];
            $str= $row['stream'];
            $str_yr= $row['start_year'];
            $end_yr= $row['end_year'];
            $clg= $row['college'];
            $prf_scl= $row['performence_scale'];
            $prf_mrk= $row['performence_marks'];
        }
    ?>
        </div class="row">
            <h5>
                <?php
                    echo $deg;
                    echo $str;
                    echo $str_yr;
                    echo $end_yr;
                ?>    
            </h5>
            <div>
                <?php
                    echo $clg;
                ?>
            </div>
            <div>
                <?php
                    echo $prf_scl;
                    echo $prf_mrk;
                ?>
            </div>
        <div> 

     <?php   
        exit;
        mysqli_close($conn);
    ?> 
                    </div>


                    <div class="row dialouge"><h4>Tell us bit about your education</h4></div>
                    <div class="col userinfo">
                        <div class="row discipline" data-toggle="modal" data-target="#graduation-modal" id="grad">Graduation
                            <i class="fa fa-plus education-fa-plus fa-x" aria-hidden="true"></i>
                        </div>
                        <div class="row discipline" data-toggle="modal" data-target="#hs-modal">XII(Higer Secondary)
                            <i class="fa fa-plus education-fa-plus fa-x" aria-hidden="true"></i>
                        </div>      

                        <div class="button-container">
                            <a href="student.php" class="previous">PREVIOUS</a>
                        </div>  
                    </div>

如果我不添加 PHP 代码，那么所有内容都会显示，但在添加以下部分后不会显示。我不明白这里有什么问题

Answer 1

<?php   
    exit;
    mysqli_close($conn);
?>

您需要从代码中删除退出，因为它会立即停止执行。

为什么我的一些 html 内容在添加一些 php 代码后被删除？

why some of my html content is getting removed after adding some php code?

php

html

mysql

web-development-server