HTML5 中的 javascript 上傳進度顯示

Question

我對 js 和 html 編程很陌生。 我正在使用以下代碼制作一個顯示文件上傳進度的進度條。 但它不適用於 tryit 編輯器

<!DOCTYPE html>
<head>
<meta charset="UTF-8">
<style>
.progress-wrapper {
    width:100%;
}
.progress-wrapper .progress {
    background-color:green;
    width:0%;
    padding:5px 0px 5px 0px;
}
</style>
<script>
function postFile() {
    var formdata = new FormData();

    formdata.append('file1', $('#file1')[0].files[0]);

    var request = new XMLHttpRequest();

    request.upload.addEventListener('progress', function (e) {
        var file1Size = $('#file1')[0].files[0].size;

        if (e.loaded <= file1Size) {
            var percent = Math.round(e.loaded / file1Size * 100);
            $('#progress-bar-file1').width(percent + '%').html(percent + '%');
        } 

        if(e.loaded == e.total){
            $('#progress-bar-file1').width(100 + '%').html(100 + '%');
        }
    });   

    request.open('post', '/echo/html/');
    request.timeout = 45000;
    request.send(formdata);
}
</script>
</head>
<form id="form1">
    <input id="file1" type="file" />
    <div class="progress-wrapper">
        <div id="progress-bar-file1" class="progress"></div>
    </div>
    <button type="button" onclick="postFile()">Upload File</button>
</form>
</html>

我也試過我的本地系統，它在這里也不起作用。 我做錯了什么？ 請告訴我如何改進代碼。 我想顯示一個進度條，顯示使用 ajax 調用的文件上傳百分比。

Answer 1

在編寫任何JavaScript之前，您需要在head添加JQuery引用。 請參閱下面的正確版本。

<!DOCTYPE html>
<head>
<meta charset="UTF-8">
<style>
.progress-wrapper {
    width:100%;
}
.progress-wrapper .progress {
    background-color:green;
    width:0%;
    padding:5px 0px 5px 0px;
}
</style>
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.2.1/jquery.js"></script>
<script>
function postFile() {
    var formdata = new FormData();

    formdata.append('file1', $('#file1')[0].files[0]);

    var request = new XMLHttpRequest();

    request.upload.addEventListener('progress', function (e) {
        var file1Size = $('#file1')[0].files[0].size;

        if (e.loaded <= file1Size) {
            var percent = Math.round(e.loaded / file1Size * 100);
            $('#progress-bar-file1').width(percent + '%').html(percent + '%');
        } 

        if(e.loaded == e.total){
            $('#progress-bar-file1').width(100 + '%').html(100 + '%');
        }
    });   

    request.open('post', '/echo/html/');
    request.timeout = 45000;
    request.send(formdata);
}
</script>
</head>
<form id="form1">
    <input id="file1" type="file" />
    <div class="progress-wrapper">
        <div id="progress-bar-file1" class="progress"></div>
    </div>
    <button type="button" onclick="postFile()">Upload File</button>
</form>
</html>

Answer 2

沒有 JQuery 的版本

<!DOCTYPE html>
<head>
<meta charset="UTF-8">
<style>
.progress-wrapper {
    width:100%;
}
.progress-wrapper .progress {
    background-color:green;
    width:0%;
    padding:5px 0px 5px 0px;
}
</style>
<script>
function postFile() {
    var formdata = new FormData();

    formdata.append('file1', document.getElementById('file1').files[0]);

    var request = new XMLHttpRequest();

    request.upload.addEventListener('progress', function (e) {
        var file1Size = document.getElementById('file1').files[0].size;
        console.log(file1Size);

        if (e.loaded <= file1Size) {
            var percent = Math.round(e.loaded / file1Size * 100);
            document.getElementById('progress-bar-file1').style.width = percent + '%';
            document.getElementById('progress-bar-file1').innerHTML = percent + '%';
        } 

        if(e.loaded == e.total){
            document.getElementById('progress-bar-file1').style.width = '100%';
            document.getElementById('progress-bar-file1').innerHTML = '100%';
        }
    });   

    request.open('post', '/echo/html/');
    request.timeout = 45000;
    request.send(formdata);
}
</script>
</head>
<form id="form1">
    <input id="file1" type="file" />
    <div class="progress-wrapper">
        <div id="progress-bar-file1" class="progress"></div>
    </div>
    <button type="button" onclick="postFile()">Upload File</button>
</form>
</html>

HTML5 中的 javascript 上傳進度顯示

問題描述

2 個解決方案

解決方案1
2 已采納 2017-12-04 17:03:04

解決方案2
0 2021-10-23 12:56:01

HTML5 中的 javascript 上傳進度顯示

問題描述

2 個解決方案

解決方案1 2 已采納 2017-12-04 17:03:04

解決方案2 0 2021-10-23 12:56:01

解決方案1
2 已采納 2017-12-04 17:03:04

解決方案2
0 2021-10-23 12:56:01