1、layui进度条样式 ：

<div id="uploadPatchForm" style="display:none" class="roundRect"><div  id="uploadLoadingDiv"><div class="layui-progress" lay-showpercent="true" lay-filter="demo" ><div class="layui-progress-bar layui-bg-red" lay-percent="0%"></div></div></div>
</div>

参照官网http://www.layui.com/demo/progress.html

2、页面代码：

监听xhr也就是XMLHttpRequest ，ajax的核心技术就是这个！！！

参考：https://www.cnblogs.com/xiaohuochai/p/6036475.html

下面是layui的上传进度展示需要依赖的函数

    //创建监听函数var xhrOnProgress=function(fun) {xhrOnProgress.onprogress = fun; //绑定监听//使用闭包实现监听绑return function() {//通过$.ajaxSettings.xhr();获得XMLHttpRequest对象var xhr = $.ajaxSettings.xhr();//判断监听函数是否为函数if (typeof xhrOnProgress.onprogress !== 'function')return xhr;//如果有监听函数并且xhr对象支持绑定时就把监听函数绑定上去if (xhrOnProgress.onprogress && xhr.upload) {xhr.upload.onprogress = xhrOnProgress.onprogress;}return xhr;}}

添加了 xhr,pogress

layui.use(['upload','element','layer'], function(){var upload = layui.upload,element = layui.element,layer = layui.layer;upload.render({elem: '#test8',url: 'upload',async: false,method: 'post',data: {upgradeType: function(){return $("input[name='upgradeType']:checked").val();}},auto: false,xhr:xhrOnProgress,progress:function(value){//上传进度回调 value进度值element.progress('demo', value+'%')//设置页面进度条},accept: 'file' //普通文件,exts: 'zip' //只允许上传压缩文件,field:'uploadFile',bindAction: '#test9',choose: function(obj){var uploadFileInput=$(".layui-upload-file").val();var uploadFileName=uploadFileInput.split("\\");$("#uploadName").text(uploadFileName[uploadFileName.length-1]);},before: function(obj){//layer.load(); //上传loading},done: function(res){layer.msg("上传成功");},error: function(index, upload){element.progress('demo', '0%');layer.msg('上传失败');}});
});

3、修改layui源码

1. 打开layui/modules/upload.js
2. 搜索ajax 
3. 找到url:
4. 添加以下代码：

    ,xhr:l.xhr(function(e){//此处为新添加功能var percent=Math.floor((e.loaded / e.total)*100);//计算百分比l.progress(percent);//回调将数值返回})
   

    

5. upload.js 中 p.prototype.config也要改，加一个xhr的定义，否则传文件时如果不设xhr会报错。

   p.prototype.config={accept:"images",exts:"",auto:!0,bindAction:"",url:"",field:"file",method:"post",data:{},drag:!0,size:0,number:0,multiple:!1,xhr:function(){}//此处需要添加},  

   参考：https://blog.csdn.net/lin452473623/article/details/80785180