Implementing Ajax Image Upload with Deletion in ThinkPHP5

While learning ThinkPHP5, a post feature required a topic image selector; using the native file upload works but introduces many compatibility issues, so an Ajax approach is adopted to enable selective deletion without such problems.

Form markup used for the upload:

<form method="post" enctype="multipart/form-data">
<div style="margin: 20px 20px 20px 10px;">
    主题图片:
    <span id="img-list-box" style="margin-left: 25px;"></span>
    <span style="display:inline-block;height: 30px;position: relative;top:0px;left:0px;">
        <a style="display: inline-block;width: 100px;height:30px;line-height: 30px;text-align:center;background: #F60;color: #FFF;">图片上传</a>
        <input type="file" name="img_src" style="width: 100px;border: 1px solid red;position: absolute;top:0px;left: 0px;height: 30px;opacity: 0;" id="up-img-file" onchange="upimg(this)">
    </span>
</div>
</form>

Since a regular form cannot meet the Ajax requirements, a click event is bound to the upload button to trigger image selection and Ajax upload.

JavaScript handling:

<script type="text/javascript" src="__STATIC__/home/js/jquery.min.js"></script>
<script type="text/javascript">
    function upimg(obj) {
        if (obj.value == "") { return; }
        var formdata = new FormData();
        formdata.append("img", $(obj)[0].files[0]); // get file
        $.ajax({
            type: 'post',
            url: '/home/note/upimg', // API endpoint
            data: formdata,
            cache: false,
            processData: false, // do not process FormData
            contentType: false, // do not set content type header
            success: function(response) {
                console.log(response);
                var html = '<p style="position: relative;margin-right: 20px;margin-bottom: 15px;width: 132px;display: inline-block;border: 1px solid #CCC;background:#EEE;">'
                        +'<span style="display: block;width: 120px;height: 80px;border: 1px solid #F2F1F0;margin: 5px;overflow: hidden;">'
                        +'<img src="' + response + '" style="width: 100%;" />'
                        +'</span>'
                        +'<input type="hidden" name="imgs[]" value="' + response + '" />'
                        +'<a onclick="delImg(this);" style="z-index: 10;display: block;top: -8px;cursor:pointer;right: -8px;position:absolute;width: 20px;height: 20px;background: #CCC;border-radius:100%;text-align:center;line-height: 20px;border: 1px solid #C1C1C1;color: #555;">X</a>'
                        +'</p>';
                $('#img-list-box').append(html);
            },
            error: function() { }
        });
    }
    function delImg(obj) {
        $(obj).parent('p').remove();
    }
</script>

On the server side, the PHP method processes the uploaded file, moves it to the public uploads directory, and returns the image path for the Ajax response:

public function upimg()
{
    // Validate
    $file = request()->file('img');
    // Move to /public/uploads/
    if ($file) {
        $info = $file->move(ROOT_PATH . 'public' . DS . 'uploads');
        if ($info) {
            $img_src = '/uploads/' . $info->getSaveName();
            echo $img_src; // return to Ajax
        } else {
            $this->error($file->getError());
        }
    }
}

After integration, the uploaded image appears with a delete button, providing a smoother user experience without page reloads.