在dartium中使用'dart：io'吗？ 有什么解决方法吗？

Question

I am new to dart and I am trying to read data from a file and use the contents to draw something canvas. In doing so I am running into 'The built-in library 'dart:io' is not available on Dartium ' issue.

I understand Dart has limitations as Javascript in that code that is running in a browser cannot natively access the File System of the running client.

At the same time are there any tips on how to read a file and also use the contents to write it to canvas?

Thanks in advance.

Answer 1

What kind of application are you trying to build?
If it runs in the browser the files are usually on the server.
If it is a normal web page you can't access user files. There is a sandboxed space accessible to be used by by the code of a webpage.
If you build something like a Chrome app you have less limitations.

You definitely can't import 'dart:io' when the could should run in the browser.
The APIs available in the browser can be found in 'dart:html'.

If you want to build a Chrome app this package provides access to the extended API http://pub.dartlang.org/packages/chrome

Answer 2

I fixed my problem by prompting the user to choose the file. Similar approach as in https://developer.mozilla.org/en-US/docs/Using_files_from_web_applications but using DART.