TS数组转JSON并且保存文件在本地

private saveJSON(data, filename) {
    if (!data) {
      alert('data is null');
      return;
    }
    if (!filename) {
      filename = 'json.json'
    }
    if (typeof data === 'object') {
      data = JSON.stringify(data, undefined, 4)
    }
    // 文件保存
    let blob = new Blob([data], { type: 'text/json' });
    let e = document.createEvent('MouseEvents');
    let a = document.createElement('a');
    a.download = filename;
    a.href = window.URL.createObjectURL(blob);
    a.dataset.downloadurl = ['text/json', a.download, a.href].join(':');
    e.initMouseEvent('click', true, false, window, 0, 0, 0, 0, 0, false, false, false, false, 0, null);
    a.dispatchEvent(e);
}