如何在vue项目中利用element_ui实现一个文件上传功能

<template>
 <el-upload class="upload-demo" action :limit="1" :file-list="formFileList" :http-request="handleUploadForm" :on-exceed="formHandleExceed" :on-remove="formHandleRemove"
 :before-upload="beforeUploadForm" accept=".csv,application/vnd.openxmlformats-officedocument.spreadsheetml.sheet,application/vnd.ms-excel">
    <el-button type="primary">上传文件</el-button>
    <span slot="tip" class="el-upload__tip" >只能上传xlsx/xls/csv文件，且不超过{{formMaxSize}}M</span>
  </el-upload>
</template>
<script>
export default {
 data () {
 return {
  formMaxSize: 10, // 上传文件大小
  formFileList: [], // 显示上传文件
  uploadFormFileList: [] // 确定上传文件
 }
 },
 methods: {
 // 开始上传前验证
 beforeUploadForm (file) {
  // 验证文件大小
  if (file.size / 1024 / 1024 > this.formMaxSize) {
  this.$message({
   message: `上传文件大小不能超过${this.formMaxSize}M!`,
   type: 'warning'
  })
  return false
  }
  // 中文乱码处理
  if (file.raw) {
  let reader = new FileReader() // 读取文件内容
  reader.readAsText(file.raw, 'gb2312') // 防止中文乱码问题，不加reader.onload方法都不会触发
  reader.onload = function (e) {
   this.contentHtml = e.target.result // txt文本内容，接下来就可以对其进行校验处理了
  }
  }
  // 验证文件类型
  var testmsg = file.name.substring(file.name.lastIndexOf('.') + 1)
  const extension = testmsg === 'xlsx' || testmsg === 'xls' || testmsg === 'csv'
  if (!extension) {
  this.$message({
   message: '上传文件只能是xlsx/xls/csv格式!',
   type: 'warning'
  })
  }
  return extension
 },
 // 移除上传列表中文件
 formHandleRemove (file, formFileList) {
  let thiz = this
  for (let i = 0; i < thiz.uploadFormFileList.length; i++) {
  if (thiz.uploadFormFileList[i].pname === file.name) {
   thiz.uploadFormFileList.splice(i, 1)
   break
  }
  }
 },
 // 允许上传文件个数验证
 formHandleExceed (files, formFileList) {
  this.$message.warning(`当前限制选择 1 个文件，本次选择了 ${files.length} 个文件，共选择了 ${files.length + formFileList.length} 个文件`)
 },
 // 上传文件
 handleUploadForm (param) {
  let thiz = this
  let formData = new FormData()
  formData.append('uid', '上传文件编号') // 额外参数
  formData.append('files', param.file)
  let loading = thiz.$loading({
  lock: true,
  text: '上传中，请稍候...',
  spinner: 'el-icon-loading',
  background: 'rgba(0, 0, 0, 0.7)'
  })
  thiz.$axios.post('http://localhost:8080/upload/file', formData).then(({data}) => {
  if (data.statusCode === 233) {
   thiz.$message('上传文件成功，' + data.message)
   thiz.formFileList = []
   thiz.uploadFormFileList = []
  } else {
   thiz.formFileList = []
   thiz.uploadFormFileList = []
   thiz.$message('上传文件失败，' + data.message)
  }
  loading.close()
  })
 }
 }
}
</script>
<style lang="scss" scoped>
</style>

export function mpp(data) {
 return new Promise(function(resolve, reject) {
  let data = {
   method: "POST",
   url:url,
   data:data
  }
  resolve(axios(data));
 })
}
<template>

<!--导入计划 -->
<div class="associationPlan">
 <el-form :model="dataModel" :rules="rules" ref="associationPlan" label-width="100px">
    <el-form-item label="项目名称：" prop="projectArry">
      <el-cascader :options="listOrgInfoList" v-model="dataModel.projectArry" :props="defaultProp" size="small" placeholder="请选择项目"  clearable :disabled="isCompany"></el-cascader>
    </el-form-item>
     <el-form-item label="计划级别：" prop="level">
      <el-select size="small" v-model="dataModel.level" placeholder="请选择：" clearable >
        <el-option v-for="(item,index) in planTypeList" :label="item.name" :value="item.number" :key="index"></el-option>
      </el-select>
      <span class="warnInfo" v-if="dataModel.level==1">一级进度计划匹配项目总工期，项目下只可建立一个，请确认后再添加！</span>
    </el-form-item>
    <el-form-item label="计划名称：" prop="name">
      <el-input v-model.number="dataModel.name" size="small"></el-input>      
    </el-form-item>   
    <el-form-item label="导入计划：">
     <el-upload accept=".mpp"  ref="uploadAdd" action="" :auto-upload="false" :http-request="uploadImg" :on-success="uploadImgSuccess" :on-remove="handleRemove">
      <el-button size="small" type="success">请选择文件</el-button>
     </el-upload> 
    </el-form-item>
        
 </el-form>
 <div class="clickBtn">
  <el-button @click="close" size="small">取消</el-button>
  <el-button @click="commit" size="small" type="primary">保存</el-button>
 </div>
</div>
</template>

<script>
import { mapState, mapActions } from 'vuex';
import { plan,mpp} from "../api/system_interface.js";
export default {
 name: "associationPlan",
 data() {
  return {
   dataModel: {
    projectId: '',
    projectArry:[],
    level:null,
    name:'',
    parentId:'0'
   },
   defaultProp: {
    children: "child",
    label: "name",
    value: "id"
   },
   //数据校验
   rules: {
    projectArry:  [{ required: true, message: "请选择项目", trigger: "blur" }],
    name:  [{ required: true, message: "请输入计划名称", trigger: "blur" }],
    level:  [{ required: true, message: "请选择计划级别", trigger: "change" }]
   
   },
   file:false,
   isCompany:false 
  };
 },
 computed: {
  ...mapState([
   'listOrgInfoList',
   'planTypeList'
  ]),
 },
 methods: {
   ...mapActions([
   'getlistOrgInfoList'
  ]),
 
  update(){
   let companyTypes = sessionStorage.getItem("companyType");
   this.isCompany = companyTypes == 4&#63;true:false;
   this.dataModel.projectArry = JSON.parse(sessionStorage.getItem("selectArry"));
  },
 
  uploadImg (f) {
    //  if(!f){
    //  this.$message.error("请上传文件!");
    //  return
    // }
     this.dataModel.projectId = this.dataModel.projectArry[this.dataModel.projectArry.length - 1];
     let param = new FormData(); //创建form对象
     param.append('file',f.file);//通过append向form对象添加数据
     param.append('level',this.dataModel.level);//添加form表单中其他数据
     param.append('projectId',this.dataModel.projectId);//添加form表单中其他数据
     param.append('planName',this.dataModel.name);//添加form表单中其他数据
     mpp(param)//上传
     .then(response=>{
      if(response.code == "200"){
       this.$message.success("上传成功!");
       this.close();
       this.$emit("refreshData");  
       onSuccess(response.data);     
      }        
     })
     .catch(({err}) => {
      f.onError()
     })  
   },
   uploadImgSuccess(response, file, fileList) {
     // 缓存接口调用所需的文件路径
     console.log('文件上传成功')
    // this.$message.success("上传成功!");
   },
   handleRemove(file, fileList) {
     // 更新缓存文件
     console.log('文件删除')
   },
 
  //重置方法
  reset() {
   const associationPlan = this.$refs["associationPlan"];
   associationPlan.resetFields();
   this.dataModel.projectId = null;
   this.dataModel.name = '';
   this.dataModel.level = '';
   this.dataModel.projectArry = [];
  },
 
  //关闭弹框
  close() {
   this.$emit("close");
   this.reset();
  },
 
  //点击提交
  commit() {
   this.$refs["associationPlan"].validate(valid => {
    if (!valid) {
     return;
    }
    this.$refs.uploadAdd.submit();
    // this.dataModel.projectId = this.dataModel.projectArry[this.dataModel.projectArry.length - 1];
    // plan(this.dataModel)
    // .then(response => {
    //  if (response.code == "200") {
    //   this.$message.success("添加成功!");
    //   this.close();
    //   this.$emit("refreshData");
    //  } else {
    //   this.$message.error(response.msg);
    //  }
    // })
    // .catch(error => {
    // });
   });
  },
 
 }
};

</script>
<style lang="scss" scoped>
.clickBtn {
 text-align: center;
}
.warnInfo{
 // color: #feba51;
 color: rgb(64, 158, 255);
}
</style>