【VUE+ElementUI】通过接口下载blob流文件设置全局Loading加载进度

下载`Blob流`文件，并以服务形式显示文件下载进度

1、下载接口增加 `config`参数，并用`...config`将该属性加入到请求中；

xxapi.js文件中设置downloadFile下载接口

// 下载文件
export function downloadFile(data, config) {return request({url: '/xx/downloadFile',method: 'post',data: data,responseType: 'blob',timeout: 120 * 60 * 1000,...config})
}

2、在页面中添加以下代码

<el-button type="text" icon="el-icon-download" @click="handleDownload(scope.row)">下载</el-button>

<script>
import { downloadFile } from "@/api/xxapi";
import { Loading } from 'element-ui'
let downloadLoadingInstance;export default {name: "DownloadFile",data() {return {downloadProgress: 0}},methods: {handleDownload(row) {var that = this;downloadLoadingInstance = Loading.service({ text: "正在下载数据，请稍候 " + that.downloadProgress + '%', spinner: "el-icon-loading", background: "rgba(0, 0, 0, 0.7)", })const config = {onDownloadProgress: progressEvent => {if (progressEvent.lengthComputable) {that.downloadProgress = Math.round((progressEvent.loaded / progressEvent.total) * 100);downloadLoadingInstance.text = "正在下载数据，请稍候 " + that.downloadProgress + '%';}}};// 从后端请求到 二进制数据，并由后端转成blobdownloadFile({ url: row.url }, config).then((response) => {let downloadName = `${row.fileName}`;this.downloadBlob(response, downloadName); // 二进制流直接取responsedownloadLoadingInstance.close(); // 关闭加载loading效果});},// 下载文件流格式的文件downloadBlob(response, downloadName) {let blob = new Blob([response], {type: "application/json;charset=utf-8",});let href = window.URL.createObjectURL(blob); // 创建下载的链接if (window.navigator.msSaveBlob) {try {window.navigator.msSaveBlob(blob, downloadName);} catch (e) {console.log(e);}} else {// 谷歌浏览器 创建a标签 添加download属性下载let downloadElement = document.createElement("a");downloadElement.href = href;downloadElement.target = "_blank";downloadElement.download = downloadName; // 下载后文件名document.body.appendChild(downloadElement);downloadElement.click(); // 点击下载document.body.removeChild(downloadElement); // 下载完成移除元素window.URL.revokeObjectURL(href); // 释放掉blob对象}}}
}
</script>