技術標籤：vue

上效果圖

upload.vue

（樣式是boostrap，不必要太在意樣式，可以自己寫）

<template>
  <div class="file-upload">
    <div class="file-upload-container" @click.prevent="triggerUpload">
      <slot v-if="fileStatus === 'loading'" name="loading"
 
>
        <button class="btn btn-primary" disabled>正在上傳...</button>
      </slot>
      <slot v-else-if="fileStatus === 'success'" name="uploaded">
        <button class="btn btn-primary">上傳成功</button>
      </slot>
      <
 
slot v-else name="default">
        <button class="btn btn-primary">點選上傳</button>
      </slot>
    </div>
    <input
      type="file"
      class="file-input d-none"
      ref="fileInput"
      @change="handleFileChange"
 

    >
  </div>
</template>
<script lang="ts">
import axios from 'axios';
import { defineComponent, ref } from "vue";
type UploadStatus = 'ready' | 'loading' | 'success' | 'error'
export default defineComponent({
  props: {
    action: {
      type: String,
      required: true
    }
  },
  setup(props) {
    const fileInput = ref<null | HTMLInputElement>(null)
    const fileStatus = ref<UploadStatus>('ready')
    const triggerUpload = () => {
      if (fileInput.value) {
        fileInput.value.click()
      }
    }
    const handleFileChange = (e: Event) => {
      const currentTarget = e.target as HTMLInputElement
      if (currentTarget.files) {
        fileStatus.value = 'loading'
        const files = Array.from(currentTarget.files)
        const formData =  new FormData()
        formData.append('file', files[0])
        axios.post(props.action, formData, {
          headers: {
            'Content-Type': 'multipart/form-data'
          }
        }).then(res => {
          console.log(res)
          fileStatus.value = 'success'
        }).catch(() => {
          fileStatus.value = 'error'
        }).finally(() => {
          if (fileInput.value) {
            fileInput.value.value = ''
          }
        })
      }
    }
    return {
      fileInput,
      triggerUpload,
      handleFileChange
    }
  }
})
</script>

使用元件的時候，傳入相對應的後端介面，即可

<Upload :action="'/api/upload'"></Upload>

egg

public 下，新建一個 comfiles 資料夾
router.js

router.post('/upload', controller.upload.uploadFiles);

app/controller/upload.js

'use strict';

const Controller = require('egg').Controller;

class UploadController extends Controller {
  async uploadFiles() {
    const { ctx } = this;
    const data = await ctx.service.upload.index();
    if (data) {
      ctx.body = data;
    } else {
      ctx.body = {
        message: '上傳失敗',
      };
    }
  }
}

module.exports = UploadController;

app/service/upload.js

'use strict';
const Service = require('egg').Service;
const fs = require('fs');
const path = require('path');
const sendToWormhole = require('stream-wormhole');


class UploadService extends Service {
  async index() {
    const ctx = this.ctx;
    const stream = await ctx.getFileStream();
    const fileName = stream.filename;

    const target = path.join(this.config.baseDir, `app/public/comfiles/${stream.filename}`);
    const result = await new Promise((resolve, reject) => {
      const remoteFileStream = fs.createWriteStream(target);
      stream.pipe(remoteFileStream);
      let errFlag;
      remoteFileStream.on('error', err => {
        errFlag = true;
        sendToWormhole(stream);
        remoteFileStream.destroy();
        reject(err);
      });

      remoteFileStream.on('finish', async () => {
        if (errFlag) return;
        resolve({ fileName, name: stream.fields.name });
      });
    });
    return result;
  }
}

module.exports = UploadService;

參考文章：https://www.cnblogs.com/qq735675958/p/9315694.html