我在ajax的帮助下上传图像，并在一个div中显示，但它不会在第一次用php上传图像时显示图像

我正在使用帮助ajax上传图像并显示它。现在我想要实现的是，一旦用户选择图像，它应该在div中可见，但是当我第一次尝试上传图像时，当数据库为空时，它不会显示任何内容。ajax正在运行的数据正在保存到数据库中，但我看不到图像你能告诉我我做错了什么吗

    <div id="timelineBackground" class="">
                <?php

                {
                    if(!$timeline_image=="")
                    {
                        $image_properties = array('src' => base_url("uploads/".$timeline_image),'width' => '900px','height'=> '400px','id'=>'coverimg', 'title' => 'That was quite a night','rel'   => 'lightbox');
                        echo img($image_properties);
                    }else{
                        $timeline_image = array(
                            'src'   => base_url("assets/img/Facebook-cover.jpg"),
                            'width' => '900px',
                            'height'=> '400px',

                        );

                        echo img($timeline_image);
                    }
                    ?>
                    <div id="timelineselector" class="grow">
                        <?php echo form_open_multipart('',["id"=>"form_cover"]); ?>
                        <input type="hidden" name="id" value="<?php echo $id ;?>">
                        <label class="icons-camera " for="timelineimage">
                           <p class="cover_upload"> <i class="fa fa-camera cover_upload" style="color:white;">&nbsp;Upload Your Cover</p></i>

                        </label>
                        <?php echo form_upload(["name"=>"timelineimage","id"=>"timelineimage" ]); ?>
                        <?php echo form_close(); ?>
                    </div>
                    <?php
                }
                ?>
            </div>

模型代码

public function timeline_upload_model($arr,$arra)
        {

            $id=$arr['id'];
             $image=$arra['name'];

        $data=array('timelineimage'=>$image,'user_id'=>$id);

         $query=$this->db->where('id',$id)->update('user_data',$data);
            //print_r($query);
            return $query;
    }

现在让我告诉你问题出在哪里

[![First Image][1]][1]
[![Second Image][2]][2]
[![Third Image][3]][3]

  [1]: https://i.stack.imgur.com/C2Rvu.png
  [2]: https://i.stack.imgur.com/4fYXJ.png
  [3]: https://i.stack.imgur.com/DG4NH.png

---

您在else部分中缺少图像标记的id

if(!$timeline_image=="")
    {
        $image_properties = array('src' => base_url("uploads/".$timeline_image),'width' => '900px','height'=> '400px','id'=>'coverimg', 'title' => 'That was quite a night','rel'   => 'lightbox');
        echo img($image_properties);
    }else{
        $timeline_image = array(
            'src'   => base_url("assets/img/Facebook-cover.jpg"),
            'width' => '900px',
            'height'=> '400px',
            'id'=>'coverimg',
        );
        echo img($timeline_image);
    }

---

我使用

ajax

上传了多个文件，并用php将其保存在数据库中，但它显示的是空数组

这是我的html代码

<form id="registration_form" method="post" enctype="multipart/form-data">
  <input type="file"   id="file" name="file[]" multiple>
</form>

这是我的php代码（update.php）

---

ajax successurl中的图像是什么样的“@shafiq您使用的是什么框架？第一次$timeline\u图像是否为空代码点火器@shafiq第一次$timeline\u图像的输出是什么？你能分享一下你的控制器代码吗？老兄，你帮了我一个大忙@沙菲克
if(!$timeline_image=="")
    {
        $image_properties = array('src' => base_url("uploads/".$timeline_image),'width' => '900px','height'=> '400px','id'=>'coverimg', 'title' => 'That was quite a night','rel'   => 'lightbox');
        echo img($image_properties);
    }else{
        $timeline_image = array(
            'src'   => base_url("assets/img/Facebook-cover.jpg"),
            'width' => '900px',
            'height'=> '400px',
            'id'=>'coverimg',
        );
        echo img($timeline_image);
    }

<form id="registration_form" method="post" enctype="multipart/form-data">
  <input type="file"   id="file" name="file[]" multiple>
</form>

$.ajax({
    url:"update.php",
    type:"post",
    data: new FormData(this),
    contentType:false,
    cache:false,
    processData:false,
    success:function(data)
    {
        alert(data);
    },
    failure:function(errormsg)
    {
        alert(errormsg);
    }
});

<?php
    $IMG = isset($_POST['file']) ? $_POST['file'] : array();
    if (!empty($IMG)) {
        $uploads_dir = 'upload/';
        echo $uploads_dir; die;
        foreach ($IMG["error"] as $key => $error) {
            if ($error == UPLOAD_ERR_OK) {
                $tmp_name = $IMG["tmp_name"][$key];
                $name = $IMG["name"][$key];
                move_uploaded_file($tmp_name, "$uploads_dir/$name");
                $name_array=mysql_real_escape_string($name);
                $value_insert[] = "('" . $name_array . "')";
            }
        }
        $values_insert = implode(',', $value_insert);
        echo "asd";
        $sql="update register set filename='$values_insert' where id='1'";
        $result = mysql_query($query);
    }else{
        echo 'empty array';
    }
?>