使用会话在网页上显示存储的数据库图像？

问：

嗨，我正在尝试使用会话将图像存储到数据库中，并且成功完成，但问题是当我上传页面并单击保存按钮时，它无法显示在我的网页上，上一张图片再次显示，但新图片成功保存到数据库中，我想将图片存储在我的文件夹中，编码如下

Html页面编码如下

<form class="form" action="accountsetting.php" method="post" enctype="multipart/form-data">
    <div class="row">
        <div class="col-12 col-sm-auto mb-3">
            <div class="mx-auto" style="width: 140px;">
                <div class="rounded-circle avatar avatar-xl mb-3">
                    <img class="rounded-circle" id="preview_avatar" name="image" src="https://imgbob.com/path/cdn/avatars /zxMvnv1q52hFyNeEGKz0UuPU5fkth5YadkXe3m26S4HODj09An.png"  
width="100" height="100">
                </div>
            </div>
        </div>
        <div class="col d-flex flex-column flex-sm-row justify-content-between mb-3">
            <div class="text-center text-sm-left mb-2 mb-sm-0">
                <h4 class="pt-sm-2 pb-1 mb-0 text-nowrap"><?php echo $_SESSION['user']['fullname']; ?></h4>
                                                                                            <p class="mb-0"><?php echo $_SESSION['user']['username']; ?></p>
                <div class="form-group mb-2 pt-2">
                    <input class='input' type='hidden' name='id' value="<?php echo $_SESSION['user']['id']; ?>" />
                    <input id="avatar" type="file" name="avatar" hidden="" accept="image/png, image/jpeg, image/jpg">
                    <button id="uploadBtn" type="button" class="btn btn-primary btn-file " >
                        <i class="fa fa-camera" aria-hidden="true"></i> &nbsp Upload Avatar
                    </button>
                </div>
                <div class="row">
                    <div class="col d-flex justify-content-end pr-5">
                        <button class="btn btn-primary " type="submit" name="profile">Save Changes</button>
                    </div>
                </div>
            </div>
        </div>
    </div>
</form>

PHP编码如下

$id = "";
if(isset($_POST['profile'])) {
    $id = $_SESSION['user']['id'];
    $file=addslashes(file_get_contents($_FILES["avatar"]["tmp_name"]));
    $query = "UPDATE users SET avatar = '$file' WHERE id = '$id'";
    $query_run = mysqli_query($db,$query);

    if($query_run) {
        echo '<script type = "text/javascript"> alert("image profile upload")</script>';
    } else {
        echo '<script type = "text/javascript"> alert("image profile not upload")</script>';
    }
}

来自 HTML 页面端的会话

<?php
include('../functions.php');
if (!isLoggedIn()) {
    $_SESSION['msg'] = "You must log in first";
    header("location: /uploadimg/loginform.php");
}

if (isset($_GET['logout'])) {
    session_destroy();
    unset($_SESSION['user']);
    header("location: /uploadimg/loginform.php");
}
if(isset($_SESSION['success']))
{
    echo $_SESSION['success'];
    unset($_SESSION['success']);
}
if(isset($_SESSION['user']['fullname']))
{

}
?>

PHP 页面端的会话

<?php 
session_start();

function isAdmin()
{
    if (isset($_SESSION['user']) && $_SESSION['user']['user_type'] == 'admin' ) {
        return true;
    }else{
        return false;
    }
}

function isLoggedIn()
{
    if (isset($_SESSION['user'])) {
        return true;
    }else{
        return false;
    }
}