const aBlob = new Blob( array, options ); 

export function downLoadFile(data: ArrayBuffer, fileNmame: string, type: string, fileType: string = 'xls'): void {

  const blob = new Blob([data], { type });

  const url = window.URL.createObjectURL(blob);

  const eleLink = document.createElement('a');

  eleLink.download = `${fileNmame}.${fileType}`;

  eleLink.style.display = 'none';

  eleLink.href = url;

  // 触发点击

  document.body.appendChild(eleLink);

  eleLink.click();

  // 然后移除

  document.body.removeChild(eleLink);

}