layui文件上传进度条（模拟）

1.修改上传组件js(没测)

https://blog.csdn.net/weixin_42457316/article/details/81017471

https://www.cnblogs.com/youmingkuang/p/9183528.html

https://fly.layui.com/jie/19430/

1、upload.js 扩展

功能利用ajax的xhr属性实现
该功能修改过modules中的upload.js文件
功能具体实现：
在js文件中添加监听函数

    //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;
         }
     }

初始化上传

//初始化上传
 upload.render({
     elem: '上传地址'
     ,url: path+'/upload/uploadVideo.do'
     ,accept: 'video'
    ,size: 512000
    ,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
     }
    ,bindAction:'#uploadvideo'
     ,before: function(input){
    //返回的参数item，即为当前的input DOM对象
        console.log('文件上传中');
    }
    ,done: function(res){
             //上传成功
           console.log(res)
     }
 });

修改modules中upload.js文件的ajax方法

 //提交文件
        $.ajax({
          url: options.url
          ,type: options.method
          ,data: formData
          ,contentType: false
          ,processData: false
          ,dataType: 'json'
          ,xhr:options.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
                options.progress(percent);//回调将数值返回
           })
          ,success: function(res){
            successful++;
            done(index, res);
            allDone();
          }
          ,error: function(e){
             console.log(e)
            aborted++;
            that.msg('请求上传接口出现异常');
            error(index);
            allDone();
          }
        });

后台代码：

        public ActionResult UploadFiles(HttpPostedFileBase fileNames)
        {
            string path = "";
            //小于20M
            if (fileNames.ContentLength > 0 && fileNames.ContentLength <= 120971520)
            {

                var fileName = Path.GetFileName(fileNames.FileName);

                string q_FN = fileName.Substring(0, fileName.LastIndexOf("."));
                string h_FN = fileName.Substring(fileName.LastIndexOf("."));

                string NewFileName = q_FN + DateTime.Now.ToString("yyyyMMddHHmmss") + h_FN;

                path = Path.Combine(Server.MapPath("/Uploadfile/"), NewFileName);
                fileNames.SaveAs(path);

                path = "/Uploadfile/" + NewFileName;
                var relt = new { tc = path };
                return Content(JsonConvert.SerializeObject(relt));
            }
            else
            {
                var relt = new { tc = "上传文件要小于20M" };
                return Content(JsonConvert.SerializeObject(relt));
            }
        }

功能到此结束！！！

列子截图：

2.模拟一个假的进度条

https://blog.csdn.net/lin452473623/article/details/80784717

layui.use(['upload','element','layer'], function(){
	var upload = layui.upload,element = layui.element,layer = layui.layer;
	var timer;//定义一个计时器
	//选完文件后不自动上传
	upload.render({
	    elem: '#test8'
	    ,url: 'upload'
	    ,async: false
	    ,method: 'post'
	    ,data: {
	        upgradeType: function(){
		    return $("input[name='upgradeType']:checked").val();//额外传递的参数
	        }
	    }
	    ,auto: false
	    ,accept: 'file' //普通文件
	    ,exts: 'zip' //只允许上传压缩文件
	    ,field:'uploadFile'
	    ,bindAction: '#test9'
	    ,choose: function(obj){//这里的作用是截取上传文件名称并显示
		var uploadFileInput=$(".layui-upload-file").val();
		var uploadFileName=uploadFileInput.split("\\");
		$("#uploadName").text(uploadFileName[uploadFileName.length-1]);
	    }
	    ,before: function(obj){ //obj参数包含的信息，跟choose回调完全一致
		layer.load(); //上传loading
		var n = 0;
		timer = setInterval(function(){//按照时间随机生成一个小于95的进度，具体数值可以自己调整
		    n = n + Math.random()*10|0;
		    if(n>95){
			n = 95;
			clearInterval(timer);
		    }
		    element.progress('demo', n+'%');
		}, 50+Math.random()*100);
	    }
	    ,done: function(res){
		clearInterval(timer);
		element.progress('demo', '100%');//一成功就把进度条置为100%
		layer.closeAll(); layer.msg('上传成功');}    ,error: function(index, upload){element.progress('demo', '0%');layer.closeAll(); //关闭所有层layer.msg('上传更新包失败');    }});});

　　

参考：https://www.layui.com/doc/modules/upload.html