本文限制用户只能上传的文件类型为：

office、pdf、图片。

本文的web-view中使用vant.js的van-uploader组件，使用该组件自带的api来获取文件和限制文件尺寸和类型

界面效果：

重要提示：
在vant.js的van-uploader组件的before-read中拿不到file对象。也拿不到file.path对象，但是可以拿到file.type和file.name。

<template>
  <div class="container">
    <van-uploader accept="*" :before-read="beforeRead" :max-count="1" :max-size="10 * 1024 * 1024" @oversize="onOversize" :after-read="afterRead">
        <!-- <div class="box-button">
          <div>
            <div class="icon-image">
              <img
                src="@/assets/images/add.png"
                class="image-style"
              />
            </div>
            <div class="box-button-text">添加文件</div>
          </div>
        </div> -->
        <div>
          <van-button round icon="plus" type="info">上传文件</van-button>
        </div>
    </van-uploader> 
  </div>
</template>
<script type="text/javascript" src="jsfile/weixin.js"></script>
<script>
import { uploadFile } from '@/api/mobileUpload.js'
import { setToken } from '@/utils/auth'
import { Toast } from 'vant';
export default {
  data() {
    return {
      fileList: [],
      isFile: [
        "image/jpeg",
        "image/png",
        "application/msword",
        "application/vnd.ms-excel",
        "application/pdf",
        "application/vnd.openxmlformats-officedocument.presentationml.presentation",
        "application/vnd.openxmlformats-officedocument.wordprocessingml.document",
      ],
    };
  },
  created() {
    console.log('拿到的参数1:', this.$route.query, window.location)
    console.log('拿到的参数2:', this.$route.query.token)
  },
  methods: {
    beforeRead(file) {
      if(file.name){
        const fileExtension = ['png','jpg','jpeg','doc','docx','pdf','xls','xlsx','ppt','pptx']
        // const fileFormat = ['image/jpeg','image/png','application/msword','application/vnd.ms-excel','application/pdf','application/vnd.openxmlformats-officedocument.wordprocessingml.document','application/vnd.openxmlformats-officedocument.spreadsheetml.sheet','application/vnd.openxmlformats-officedocument.presentationml.presentation']
        const arr = file.name.split('.')
        const extensionName = arr[arr.length-1]
        // const index = fileFormat.indexOf(file.type)
        const index = fileExtension.indexOf(extensionName)
        if (index===-1) {
          Toast("仅支持上传图片、office、pdf格式的文件")
          return false;
        }
        return true;
      } else {
        return true
      }
    },
    // 所上传的文件超过尺寸事件
    onOversize() {
      Toast('文件大小不能超过 10M');
    },
    afterRead(param){
      console.log('拿到的文件消息:', param)
      const file = param.file
      // this.test2 = JSON.stringify(file.path)
      // this.test = JSON.stringify(file)
      // const fileExtension = ['png','jpg','jpeg','doc','docx','pdf','xls','xlsx','ppt','pptx']
      // const arr = file.path.split('.')
      // const extensionName = arr[arr.length-1]
      // const index = fileExtension.indexOf(extensionName)
      // if (index===-1) {
      //   Toast("仅支持上传图片、office、pdf格式的文件2")
      //   return
      // }
      const str = this.$route.query.token
      setToken(str)
      console.log('文件信息', file)
      const formData = new FormData()
      formData.append('name', file.name)
      formData.append('file', file)
      uni.getEnv(res => {  
        console.log('当前环境1：', res);
        // 如果是微信小程序环境
        if(res.miniprogram){
          console.log('确认是微信小程序运行环境')
          // 上传后端
          uploadFile(formData).then(response => {
            const data = response.data
            // 如果上传成功
            if (data.code == 200) {
              console.log('上传成功', data)
              // 转到小程序首页
              uni.postMessage({
                data: {
                    mobileResult: data
                }
              });
              uni.reLaunch({
                url: '/pages/home/index?mobileResult=' + encodeURIComponent(JSON.stringify(data))
              });
            } else {
              // 如果上传失败
              console.log('文件上传失败',response)
              uni.postMessage({
                data: {
                    mobileResult: data
                }
              });
              uni.reLaunch({
                url: '/pages/home/index?mobileResult=' + encodeURIComponent(JSON.stringify(data)),
                  animationType: 'none',
                  animationDuration: 0
              });
            }
          })
        } else {
          // 考虑从浏览器直接进入的情况
          Toast('请从微信小程序进入');
        }
      })

    }
  },
};
</script>

<style scoped>
.container {
  width: 100%;
  height: calc(100vh - 80px);
  display: flex;
  justify-content: center;
  align-items: center;
  box-sizing: border-box;
}
.image-style{
  width: 30px;
  height: 30px
}
.box-button {
  width: 100px;
  height: 100px;
  background: rgb(18, 125, 250);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
}
.box-button-text {
  color: white;
  font-size: 13px;
}
.box-button:active {
  width: 100px;
  height: 100px;
  background: red;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
}
::v-deep .el-upload-dragger {
  background-color: #eaecf3;
  border: none;
}
</style>