Javascript 在web应用程序中从google.script.run下载PDF

我试图实现的是从GoogleScriptWeb应用程序下载sheet作为.PDF文件，但我有一个问题：输出文件可能编码错误，UTF-8也不起作用

例如：

好文件： 从带有export？exportFormat=pdf的链接下载

%PDF-1.4
% âăĎÓ
4
0
obj
<<
/Type
/Catalog
/Names
<<
/JavaScript
3

...

HTML JavaScript index.HTML：

...

function downloadURI(uri, name) {
  var link = document.createElement('a');
  link.download = name;
  link.href = uri;
  document.body.appendChild(link);
  link.click();
  document.body.removeChild(link);
  delete link;
}

google.script.run.withSuccessHandler((data) => {

  var uri = 'data:application/pdf;charset=ISO-8859-1;base64,' + encodeURIComponent(data);
  downloadURI(uri, 'test.pdf');

}).withFailureHandler((err) => {
  console.log(err);
}).test();

当使用DriveApp.createFileblob将var blob=response.getBlob的blob创建为PDF文件时，如果您可以完整地看到PDF，该修改如何

发件人： 致： 参考： 如果这不是你问题的直接解决方案，我很抱歉

function doGet(e) {
    return HtmlService.createTemplateFromFile('index').evaluate();
}

function test() {
  var spreadsheet = SpreadsheetApp.getActiveSpreadsheet(),
      sheet = spreadsheet.getActiveSheet();

  var url = spreadsheet.getUrl().replace(/edit$/, '');
  var url_ext = 'export?exportFormat=pdf&format=pdf&gid=' + 
                 sheet.getSheetId();

  var options = {
    headers: {
      'Authorization': 'Bearer ' +  ScriptApp.getOAuthToken(),
    }
  };

  var response = UrlFetchApp.fetch(url + url_ext, options);
  var blob = response.getBlob();

  var charset = 'ISO-8859-1';
  var str = blob.getDataAsString(charset);

  return Utilities.base64Encode(str);
}

...

function downloadURI(uri, name) {
  var link = document.createElement('a');
  link.download = name;
  link.href = uri;
  document.body.appendChild(link);
  link.click();
  document.body.removeChild(link);
  delete link;
}

google.script.run.withSuccessHandler((data) => {

  var uri = 'data:application/pdf;charset=ISO-8859-1;base64,' + encodeURIComponent(data);
  downloadURI(uri, 'test.pdf');

}).withFailureHandler((err) => {
  console.log(err);
}).test();

var blob = response.getBlob();
var charset = 'ISO-8859-1';
var str = blob.getDataAsString(charset);
return Utilities.base64Encode(str);

var blob = response.getBlob();
return Utilities.base64Encode(blob.getBytes());