整理文档，搜刮出一个vue中用H5实现文件上传的方法实例代码，稍微整理精简一下做下分享。

1.图片上传

 <img v-if="personInfo.photoUrl" :src="headPreFix + personInfo.photoUrl" style="height:126px;max-width:133px;margin: 25px 0;">
 <img v-else src="../../assets/default.png" style="height:126px;max-width:133px;margin: 25px 0;">

<form id="form1" enctype="multipart/form-data" method="post" action="">
        <div style="height:0px; overflow:hidden; position:absolute;">
         <input type="file" tabIndex="-1" accept="image/jpeg,image/x-png,image/gif" name="file" style="padding-left:10px" id="fileToUpload" @change="fileSelected()"/>
        </div>
        <button type="button" class="btn btn-default btn-xs" onclick="document.getElementById('fileToUpload').click()">上传</button>
        <button type="button" class="btn btn-default btn-xs" @click="deleteImg">删除</button>
       </form>

// 上传图片
  'fileSelected': function () {
   var that = this
   let files = document.getElementById('fileToUpload').files
   if (files && files.length) {
    var fd = new FormData()
    fd.append('file', files[0])
    var reader = new window.FileReader()
    // 图片大小 100KB
    var fileSize = 100 * 1024
    reader.readAsDataURL(files[0])
    reader.onload = function (e) {
     if (e.target.result.length > fileSize) {
      that.$dispatch('show-alert', 'msg_1016')
      document.getElementById('fileToUpload').value = ''
     } else {
      var xhr = new XMLHttpRequest()
      xhr.addEventListener('load', that.uploadComplete, false)
      xhr.open('POST', that.$root.appBaseUrl + 'fileUpload/singleFileUpload')
      xhr.send(fd)
     }
    }
   }
  },
  // 上传成功
  'uploadComplete': function (evt) {
   this.personInfo.photoUrl = (evt.target.responseText).replace('\\', '/')
   document.getElementById('fileToUpload').value = ''
  },
  // 删除图片
  'deleteImg': function () {
   this.personInfo.photoUrl = ''
  },

computed: {
  headPreFix: function () {
   let params = window.localdicts.dicts.ph_params.systemParam
   if (params.storageType === 1) {
    return params.storageUrl
   }
   return this.$root.appBaseUrl
  }
}