<a> 标签 下载 

HTML原理 

//创建URL 利用a标签属性下载
<a href="url" download="<fileName>">导出/下载</a>

JS实现方法

      let blobUrl = window.URL.createObjectURL(result);
      const a = document.createElement('a')
      a.style.display = 'none';
      a.download = '<線體信息>';
      a.href = blobUrl;
      a.click();

数据导出 

exportFile() {
    fetch(url, {
      method: 'POST',
      body: JSON.stringify(arg),
      headers: {
        'Content-Type': 'application/json; charset=utf-8'
      }
    }).then(res => {
      //二进制文件转换  .json()
      return res.blob();
    }).then(result => {
      let blobUrl = window.URL.createObjectURL(result)
      const a = document.createElement('a')
      a.style.display = 'none';
      a.download = '<fileName>';
      a.href = blobUrl;
      a.click();
    });
  }

//GET
    let url = `${this.intSrv.daoChuData}?flag=${this.parmas.flag}&lineName=${this.parmas.lineName}`
    const a = document.createElement('a')
    a.style.display = 'none';
    a.setAttribute('target', '_blank');
    a.href = url;
    a.click();