模拟app端上传图片

<sys:fileUpload fieldName="picList" contentId="true" valueList="${picturesList}"></sys:fileUpload>
                <form:hidden id="nameImage" path="prePhoto" htmlEscape="false" maxlength="255" class="input-large"/>
            

<%@ taglib prefix="sys" tagdir="/WEB-INF/tags/sys" %>

<%@ tag language="java" pageEncoding="UTF-8"%>
<%@ include file="/WEB-INF/views/include/taglib.jsp"%>
<%@ attribute name="tag" type="java.lang.String" required="false" description="每个列表的标识，如需求分隔不同的列表页，应传入"%>
<%@ attribute name="fieldName" type="java.lang.String" required="true" description="图片对应的字段名称"%>
<%@ attribute name="valueList" type="java.util.List" required="true" description="图片背景实体"%>
<%@ attribute name="contentId" type="java.lang.Boolean" required="true" description="是否包含id"%>
<c:if test="${empty isLoaded}">
    <c:set var="isLoaded" value="1" scope="request" />
    <link href="${ctxStatic}/fileupload/fileUpload.css" rel="stylesheet" />
    <script type="text/javascript" src="${ctxStatic }/fileupload/fileUpload.js"></script>
</c:if>
<script type="text/javascript">

$(function(){
            
              <c:forEach var="picture" varStatus="status" items="${picturesList}">  
                 if(‘${picture.userPhotos}‘!=‘‘){
                     var a = document.getElementById(‘${fieldName}[${status.index}]‘);
                     onloadChange(a,‘${picture.userPhotos}‘);
                 }
              </c:forEach>
        });
</script>
<div class="section">
<div class="article">
<c:forEach items="${valueList}" var="picture" varStatus="status">
<div class="item">
<img class="addImg" onclick="clickImg(this);" src="${picture.urlPath }">
<c:if test="${contentId}">
<input type="hidden" class="itemId" value="${picture.id}" name="${fieldName}[${status.index}].id"/>
<input width="200px;" class="userPhotos" id="userPhotos" type="hidden" value="${picture.userPhotos}" name="${fieldName}[${status.index}].userPhotos"/>
</c:if>

<input name="${fieldName}[${status.index}].files" id="${fieldName}[${status.index}]"  class="upload_input" onchange="change(this)" type="file" accept="image/*">
<div class="preBlock">
<img class="preview" id="preview" alt="" name="pic" width="190" height="190">
</div>
<img class="delete" onclick="deleteImg(this)" src="${ctxStatic }/images/delete.png">
</div>
</c:forEach>
<div style="clear: left;"></div>
</div>
</div>

  //点击
  var clickImg = function(obj){
    $(obj).parent().find(‘.upload_input‘).click();
  }
  //删除
  var deleteImg = function(obj){
    $(obj).parent().find(".userPhotos").val(‘‘);
    $(obj).parent().find(‘img.preview‘).attr("src","");
    //IE9以下
    $(obj).parent().find(‘img.preview‘).css("filter","");
    $(obj).hide();
    $(obj).parent().find(‘.addImg‘).show();
  }
  //选择图片
  function change(file) {
      
      //预览
      var pic = $(file).parent().find(".preview");
      $(file).parent().find(".userPhotos").val(file.value);
      //添加按钮
      var addImg = $(file).parent().find(".addImg");
      //删除按钮
      var deleteImg = $(file).parent().find(".delete");

      var ext=file.value.substring(file.value.lastIndexOf(".")+1).toLowerCase();

       // gif在IE浏览器暂时无法显示
       if(ext!=‘png‘&&ext!=‘jpg‘&&ext!=‘jpeg‘){
          if (ext != ‘‘) {
            alert("图片的格式必须为png或者jpg或者jpeg格式！"); 
          } 
           return;
       }
       //判断IE版本
       var isIE = navigator.userAgent.match(/MSIE/)!= null,
           isIE6 = navigator.userAgent.match(/MSIE 6.0/)!= null;
           isIE10 = navigator.userAgent.match(/MSIE 10.0/)!= null;
       if(isIE && !isIE10) {
          file.select();
          var reallocalpath = document.selection.createRange().text;
           // IE6浏览器设置img的src为本地路径可以直接显示图片
           if (isIE6) {
              pic.attr("src",reallocalpath);
              userPhotos.value = reallocalpath;
           }else{
              // 非IE6版本的IE由于安全问题直接设置img的src无法显示本地图片，但是可以通过滤镜来实现             
              pic.css("filter","progid:DXImageTransform.Microsoft.AlphaImageLoader(sizingMethod=‘scale‘,src=\"" + reallocalpath + "\")");
              // 设置img的src为base64编码的透明图片 取消显示浏览器默认图片
              pic.attr(‘src‘,‘data:image/gif;base64,R0lGODlhAQABAIAAAP///wAAACH5BAEAAAAALAAAAAABAAEAAAICRAEAOw==‘);             
           }
           addImg.hide();
           deleteImg.show();
       }else {
          html5Reader(file,pic,addImg,deleteImg,userPhotos);
       }
  }
  
  
  
  //onload展示图片
  function onloadChange(file,src) {
      
      //预览
      var pic = $(file).parent().find(".preview");
      //添加按钮
      var addImg = $(file).parent().find(".addImg");
      //删除按钮
      var deleteImg = $(file).parent().find(".delete");

      
          pic.attr("src",src);
      
      addImg.hide();
      deleteImg.show();
  }
  
  
  
 //H5渲染
  function html5Reader(file,pic,addImg,deleteImg){
      debugger;
     var file = file.files[0];
     var reader = new FileReader();
     reader.readAsDataURL(file);
     reader.onload = function(e){
         
         pic.attr("src",this.result);
     }
     addImg.hide();
     deleteImg.show();
  }