[js] - 前端FileReader使用,适用于文件上传预览.(并未传入后端)

<body>

    <div class="box">

        <div class="container">

            <ul>

                <li>

                    <form id="index" enctype='multipart/form-data' style="display:none;">

                        <div class="form-group">

                            <label for="upteainput">上传文件</label>

                            <input id="upteainput_index" name="upfile" type="file" class="form-control-file">

                        </div>

                    </form>

                    <div class="img_box1">

                            <video width="100%" height="200" controls="" controlslist="nodownload nofullscreen" id="video" class="index" src="">

                            </video>

                    </div>

                </li>

            </ul>

        </div>

    </div>

    <script src="./jquery.min.js"></script>

    <script>

        $(".img_box1").click(function () {

            $("#upteainput_index").click();

        })

        let uploadFile;

        $("#upteainput_index").change(function () {

            uploadFile = $("#upteainput_index")[0].files[0];

            // console.log(uploadFile)

            //创建文件读取对象

            var reader = new FileReader();

            reader.readAsDataURL(uploadFile);

            //文件读取完毕

            reader.onload = function(){

                console.log(this.result)

                $(".index").attr("src", this.result)

            }

        });

    </script>

</body>

后续操作可以继续参照 : https://www.cnblogs.com/ukzq/p/10687402.html (前端组员改善了页面代码,但先不贴出来了)