本文主要介紹new XMLHttpRequest()監聽附件上傳進度，解決優化loading長時間加載，用戶等待問題
一、存在問題
經測試發現，new XMLHttpRequest()在附件上傳請求中，WIFI關閉切4G上傳，上傳進度不會持續；4G不關閉打開WIFI會繼續上傳，但等待時間過長，實際上是4G在上傳，倘若關閉4G網絡，上傳進度終止。
二、相關代碼
2.1 HTML
<div class="process-wrapper" id="processWrap">
<div class="process-face"></div>
<img class="close-icon" id="closeBtn" src="../../images/close.png" alt="">
<div class="process">
<div class="process-inner" id="processInner" style="width:50%"></div>
<div class="process-value">
<span>提交中...</span>
<span id="process">0%</span>
</div>
</div>
</div>
2.2 CSS樣式
/* 附件上傳進度條 */
.process-wrapper{
-moz-user-select:none;
position: fixed;
left: 0;
top: 0;
bottom: 0;
right: 0;
z-index: 10000;
display: none;
}
.process-face{
width: 100%;
height: 100%;
background-color: #000;
opacity: 0.7;
position: fixed;
}
.close-icon{
width: 26px;
height: 26px;
position: fixed;
left: 50%;
top: calc( 50% + 40px );
transform: translate(-50%,-50%);
}
.process{
width: 90%;
height: 30px;
background-color: #fff;
border-radius: 30px;
overflow: hidden;
position: absolute;
left: 50%;
top: 50%;
transform: translate(-50%,-50%);
text-align: center;
font-size: 14px;
line-height: 30px;
color: #999;
}
.process-inner{
width: 100%;
height: 30px;
position: absolute;
left: 0;
top: 0;
background-color: #0079C1;
transition: 0.1s;
z-index: -1;
}
2.3 JS
(function(app, doc) {
var $processWrap = document.getElementById("processWrap"),
$closeBtn = document.getElementById("closeBtn"),
xhr = new XMLHttpRequest();
doc.addEventListener('netchange', onNetChange, false);
function onNetChange() {
if ($processWrap.style.display != "none") {
$processWrap.style.display = "none";
xhr.abort();
mui.toast('網絡中斷請重試');
}
}
doSend: function() {
app.ajaxFile({ //封裝好的ajax請求
url: "",
data: FormData,
xhr: xhr,
success: function(r) {
if (r == '1') {
mui.toast("保存成功");
// 上傳成功邏輯處理
} else {
$processWrap.style.display = "none";
mui.toast(app.netError);
}
},
error: function(r) {
$processWrap.style.display = "none";
},
progress: function(e) {
if (e.lengthComputable) {
var progressBar = parseInt((e.loaded / e.total) * 100);
if (progressBar < 100) {
$progress.innerHTML = progressBar + "%";
$processInner.style.width = progressBar + "%";
}
}
},
timeout:function(){
$processWrap.style.display = "none";
}
});
})
mui.plusReady(function() {
$closeBtn.addEventListener("tap",function(){
setTimeout(function(){
$processWrap.style.display = "none";
xhr.abort();
}, 400);
})
});
})(app, document);
三、app.js封裝ajax請求
var $ajaxCount = 0;
window.app = {
//ajaxFile超時時間
fileTimeout: 180000,
ajaxFile: function(option) {
$ajaxCount++;
var _ajaxCount = $ajaxCount;
if (!option.error) {
option.error = ajaxError; // 請求失敗提示
}
if (option.validateUserInfo == undefined) option.validateUserInfo = true;
var xhr = option.xhr || new XMLHttpRequest();
xhr.timeout = app.fileTimeout;
xhr.open('POST', app.getItem(app.localKey.url) + option.url, true);
xhr.onreadystatechange = function() {
if (xhr.readyState == 4 && xhr.status == 200) {
var r = xhr.responseText;
if (r) {
r = JSON.parse(r);
}
if (_ajaxCount == $ajaxCount) {
option.success && option.success(r);
}
}
}
xhr.upload.onprogress = function (e) {
option.progress(e);
}
xhr.onerror = function(e) {
option.error(e); // 添加 上傳失敗后的回調函數
}
xhr.ontimeout = function(e){
option.timeout(e);
app.closeWaiting();
$.toast("請求超時,請重試");
xhr.abort();
}
xhr.send(option.data);
},
}
拓展：后端NodeJS實現代碼
const express = require("express");
const multer = require("multer");
const expressStatic = require("express-static");
const fs = require("fs");
let server = express();
let upload = multer({ dest: __dirname+'/uploads/' })
// 處理提交文件的post請求
server.post('/upload_file', upload.single('file'), function (req, res, next) {
console.log("file信息", req.file);
fs.rename(req.file.path, req.file.path+"."+req.file.mimetype.split("/").pop(), ()=>{
res.send({status: 1000})
})
})
// 處理靜態目錄
server.use(expressStatic(__dirname+"/www"))
// 監聽服務
server.listen(8080, function(){
console.log("請使用瀏覽器訪問 http://localhost:8080/")
});
到此這篇關于Html5 new XMLHttpRequest()監聽附件上傳進度的文章就介紹到這了,更多相關Html5 監聽附件上傳內容請搜索腳本之家以前的文章或繼續瀏覽下面的相關文章，希望大家以后多多支持腳本之家！
