HTML实现文件拖动上传

浏览数：45 / 时间：2015年06月09日
在大型企业的开发过程中，很多比较有趣而实际的功能往往都是让大家望而却步，我给大家带来一个百度云盘和360云盘的HTML5多文件拖动上传技术：
1：记得导入:common-fileupload.jar包.

上传upload.jsp页面
<%@page import="org.apache.struts2.json.JSONUtil"%>
<%@page import="java.io.File"%>
<%@page import="org.apache.commons.fileupload.FileItem"%>
<%@page import="org.apache.commons.fileupload.servlet.ServletFileUpload"%>
<%@page import="org.apache.commons.fileupload.disk.DiskFileItemFactory"%>
<%@page import="org.apache.commons.fileupload.FileItemFactory"%>
<%@page import="java.text.DecimalFormat"%>
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
 request.setCharacterEncoding("UTF-8");
 response.setCharacterEncoding("UTF-8");
 //获取文件的上传的具体目录
 String realPath = request.getRealPath("/");
 //定义上传的目录
 String dirPath = realPath+"/upload";
 File dirFile = new File(dirPath);
 //自动创建上传的目录
 if(!dirFile.exists())dirFile.mkdirs();
 //上传操作  
  FileItemFactory factory = new DiskFileItemFactory();  
 //
   ServletFileUpload upload = new ServletFileUpload(factory);  
 String fileName = null;
 HashMap<String,Object> map = new HashMap<String,Object>();
  try{  
      List items = upload.parseRequest(request);  //3name=null name=null
   if(null != items){  
          Iterator itr = items.iterator();  
          while(itr.hasNext()){  
              FileItem item = (FileItem)itr.next();  
              if(item.isFormField()){  
                  continue;  
              }else{  
              fileName = item.getName();
              int pos = fileName.lastIndexOf(".");
              String ext = fileName.substring(pos, fileName.length());
                 fileName = UUID.randomUUID().toString()+ext;
 //上传文件的目录
                 File savedFile = new File(dirPath,fileName);  
                 item.write(savedFile);  
                 map.put("name",item.getName());//文件的原始名称
                 map.put("newName",fileName);//文件的新名称
                 map.put("size",item.getSize());//文件的真实大小
                 map.put("url","upload/"+fileName);//获取文件的具体服务器的目录
                 //我可以建立一个文件表。把上传的文件存在表中.--文件夹表一个文件表---云盘
              }  
          }  
   }  
 }catch(Exception e){  
    
 } 
  out.print(JSONUtil.serialize(map));
%>
main.jsp
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<!DOCTYPE HTML>
<html>
  <head>
    <title>潭州学院html5拖动文件上传</title>
 <style>
 *{padding:0px;margin:0px}
 body{font-family: "微软雅黑";font-size: 12px;background: #394E48;color:#fff;}
 .demo{width:900px; margin:50px auto;position: relative;}
 #drop_area{width:100%; height:100px; border:3px dashed silver; line-height:100px; text-align:center; font-size:36px; color:#d3d3d3}
 #preview{width:900px; overflow:hidden;border:1px dashed silver; margin-top:10px;}
 #preview div{float: left;padding: 9px;text-align: center;margin:6px;background:#f9f9f9;width:195px;height: 160px;}
 #preview img{width: 80px;height: 80px;}
 #program{background:#999; height:100px;color:#d3d3d3;position: absolute;top:0px;left:0px;background:linear-gradient(#141414,red);opacity:0.5}
 </style>
  </head>
  <body> 
   <div id="main">
    <div class="demo">
     <div style="text-align: center;margin-bottom: 20px;"><h1 style="font-size: 36px;">潭州学院首席架构师--KeKe老师(QQ:792185203)</h1></div>
     <div id="program"></div>
 <div id="drop_area">将图片拖拽到此区域</div>
 <div id="preview"></div>
    </div>
 </div>
   
   <script type="text/javascript">
   
   var timer = null;
   //拖离事件-离开的时候调用
   document.ondragleave =function(e){
   e.preventDefault();
   document.getElementById("drop_area").style.background="none";
   console.log("拖动移动离开的时候");
   };
   
   //拖方后
   document.ondrop =function(e){
   e.preventDefault();
   document.getElementById("drop_area").style.background="none";
   document.getElementById("drop_area").innerHTML = "请稍后，文件上传中...";
   var p = 0;
   timer = setInterval(function(){
   if(p>=100)p=0;
   document.getElementById("program").style.width=p+"%";
   p++;
   },17);
   console.log("拖动抬起的时候");
   };
   
   //拖动移动的时候
   document.ondragover =function(e){
   e.preventDefault();
   document.getElementById("drop_area").style.background="linear-gradient(#141414,#ff0000)";
   console.log("拖动移动的时候");
   };
   
   document.ondragenter =function(e){
   e.preventDefault();
   document.getElementById("drop_area").style.background="#141414";
   console.log("拖动按下的时候");
   };
   
   function tmupload(){
   var box = document.getElementById("drop_area"); //拖拽区域
   box.addEventListener("drop",function(e){//监听拖放后事件
   e.preventDefault();//取消浏览器的默认行为
   //获取文件对象
   var fileList = e.dataTransfer.files;
   //检查是否拖拽文件到页面
   var length = fileList.length;
   if(length==0){
   return false;
   }
   
   
   for(var i=0;i<length;i++){
   var img = window.webkitURL.createObjectURL(fileList[i]);
   var filename = fileList[i].name;
   var filesize = fileList[i].size;
   var str = "<div><img src=‘"+img+"‘><p>图片名称："+filename+"</p><p>大小："+filesize+"KB</p></div>";
   document.getElementById("preview").innerHTML +=str;
   
   //通过XMLHttpRequest(ajax)上传
   var xhr = new XMLHttpRequest();
   xhr.open("post","upload.jsp", true);
   xhr.setRequestHeader("X-Requested-With", "XMLHttpRequest");
   //利用FormData动态发送表单数据
   var fd = new FormData();
   fd.append("doc", fileList[i]);
   xhr.send(fd);
   
   xhr.onreadystatechange = function(){
   if(xhr.readyState==4 && xhr.status==200){
   setTimeout(function(){
    clearInterval(timer);
    document.getElementById("drop_area").innerHTML = "请稍后，文件上传中...";
    document.getElementById("program").style.width="0%";
   },2000);
   }
   };
   
   
   }
   });
   }
   
   tmupload();//开始上传
   </script>
  </body>
</html>