flutter - Flutter如何从url获取pdf文件

Question

我正在使用 Flutter 开发网站，我正在尝试使用 pdf 文件添加用户策略，该文件位于 ms 一个驱动器。

我想从 url 获取这个 pdf 文件并想在屏幕上表示。

void initState() {
    _pdfController = PdfController(
        document: PdfDocument.openAsset(widget.pdfURLs[widget.index]));
    getFileFromUrl(
        'https://www.w3.org/WAI/ER/tests/xhtml/testfiles/resources/pdf/dummy.pdf');
    super.initState();
  }

  void getFileFromUrl(String uri) async {
    var fileName = 'testonline';
    try {
      var _uri = Uri.parse(uri);
      var data = await http.get(_uri);
      var bytes = data.bodyBytes;
      var dir = await getApplicationDocumentsDirectory();
      File file = File("${dir.path}/" + fileName + ".pdf");
      print(dir.path);
      File urlFile = await file.writeAsBytes(bytes);
      _pdfController = PdfController(document: PdfDocument.openFile(dir.path));
    } catch (e) {
      throw Exception("Error opening url file");
    }
  }

下面的代码是我用于移动应用程序的代码，它运行良好，但我在网站上遇到错误。

Error: Exception: Error opening url file
    at Object.throw_ [as throw] (http://localhost:49158/dart_sdk.js:5037:11)
    at getFileFromUrl (http://localhost:49158/packages/clio_application_portal/screens/membership_agreement_screen.dart.lib.js:1304:23)
    at getFileFromUrl.throw (<anonymous>)
    at http://localhost:49158/dart_sdk.js:37379:38
    at _RootZone.runBinary (http://localhost:49158/dart_sdk.js:37249:59)
    at _FutureListener.thenAwait.handleError (http://localhost:49158/dart_sdk.js:32511:48)
    at handleError (http://localhost:49158/dart_sdk.js:33044:51)
    at Function._propagateToListeners (http://localhost:49158/dart_sdk.js:33070:17)
    at _Future.new.[_completeError] (http://localhost:49158/dart_sdk.js:32920:23)
    at async._AsyncCallbackEntry.new.callback (http://localhost:49158/dart_sdk.js:32956:31)
    at Object._microtaskLoop (http://localhost:49158/dart_sdk.js:37497:13)
    at _startMicrotaskLoop (http://localhost:49158/dart_sdk.js:37503:13)
    at http://localhost:49158/dart_sdk.js:33274:9

是否可以从网站中的 url 获取 pdf 文件？

谢谢阅读..

标签： flutter