vue.js图片转Base64上传图片并预览的实现方法

 <el-upload
   ref='upload'
   :auto-upload='false' 
   :file-list="fileList" 
   :multiple='false'
   :limit="1"
   :on-exceed="handleExceed"
   :http-request="uploadFiles" 
   accept="image/jpeg,image/gif,image/png"
   action=''
   :on-change='changeUpload'      
   >
  <el-button slot="trigger" size="mini" type="primary">选取图片</el-button>
  <span>&nbsp;</span>
  <el-button @click='uploadFiles' size="mini" type="primary">点击上传</el-button>
 </el-upload>  

  //点击上传图片,上传成功返回图片路径 
  uploadFiles(){
    var That=this;
   let file=this.$refs.upload.$refs['upload-inner'].$refs.input; //获取文件数据
   let fileList=file.files;   
   var imgFile;
   let reader = new FileReader();   //html5读文件
   reader.readAsDataURL(fileList[0]); //转BASE64    
   reader.onload=function(e) {    //读取完毕后调用接口
    imgFile = e.target.result;
    let obj={
      id: "loginLogo",
      configGroup: "logo",
      configItem : "loginLogo",
     itemValue : imgFile  
    }
    return BaseApi.uploadFiles(obj).then((res)=>{
      if(res.status=='SUCCESS'){
        AlertBox('图片上传成功！','success',true).then(()=>{
          return That.getSysLogo(); //调用获取base64数据接口
        });
      }else{
        Alert('图片上传失败',res);
        return ''
      }
    })

   };     
  },