問題描述
我正在嘗試使用 XMLHttpRequest
(使用最近的 Webkit)下載二進制文件,并使用這個簡單的函數對其內容進行 base64 編碼:
I'm trying to download a binary file using XMLHttpRequest
(using a recent Webkit) and base64-encode its contents using this simple function:
附帶說明,以上所有內容都是標準的 Javascript 內容,包括 btoa()
和 encodeURIComponent()
:https://developer.mozilla.org/en/DOM/window.btoa
As a side note, everything above is standard Javascript stuff, including btoa()
and encodeURIComponent()
: https://developer.mozilla.org/en/DOM/window.btoa
這很順利,我什至可以使用 Javascript 解碼 base64 內容:
This works pretty smoothly, and I can even decode the base64 contents using Javascript:
現在,我想使用 Python 解碼 base64 編碼的內容,它使用一些 JSON 字符串來獲取 base64encoded
字符串值.天真地這就是我所做的:
Now, I want to decode the base64-encoded contents using Python which consume some JSON string to get the base64encoded
string value. Naively this is what I do:
但生成的文件無效,看起來操作與 UTF-8、編碼或我仍然不清楚的東西混淆了.
But the resulting file is invalid, looks like the operation's messaed up with UTF-8, encoding or something which is still unclear to me.
如果我嘗試在將 UTF-8 內容放入目標文件之前對其進行解碼,則會引發(fā)錯誤:
If I try to decode UTF-8 contents before putting them in the destination file, an error is raised:
附帶說明,這是同一文件的兩個文本表示形式的屏幕截圖;左側:原件;右側:從 base64 解碼字符串創(chuàng)建的字符串:http://cl.ly/0U3G34110z3c132O2e2x
As a side note, here's a screenshot of two textual representations of a same file; on left: the original; on right: the one created from the base64-decoded string: http://cl.ly/0U3G34110z3c132O2e2x
在嘗試重新創(chuàng)建文件時,是否有已知的技巧來規(guī)避這些編碼問題?您自己將如何實現這一目標?
Is there a known trick to circumvent these problems with encoding when attempting to recreating the file? How would you achieve this yourself?
非常感謝任何幫助或提示:)
Any help or hint much appreciated?:)
推薦答案
所以我在回答自己——對此感到抱歉——但我認為這對像我這樣迷失的人可能有用;)
So I'm answering to myself — and sorry for that?— but I think it might be useful for someone as lost as I was?;)
所以你必須使用 ArrayBuffer 并設置 responseType
XMLHttpRequest
對象實例的屬性到 arraybuffer
用于檢索原生字節(jié)數組,可以使用以下便捷函數將其轉換為 base64(找到 那里,作者在這里可能有福了):
So you have to use ArrayBuffer and set the responseType
property of your XMLHttpRequest
object instance to arraybuffer
for retrieving a native array of Bytes, which can be converted to base64 using the following convenient function (found there, author may be blessed here):
所以這是一個有效的代碼:
So here's a working code:
這將記錄一個有效表示二進制文件內容的base64編碼字符串.
This will log a valid base64 encoded string representing the binary file contents.
對于無法訪問 ArrayBuffer
并且 btoa()
編碼字符失敗的舊瀏覽器,這是另一種獲取任何二進制文件的 base64 編碼版本:
For older browsers not having access to ArrayBuffer
and having btoa()
failing on encoding characters, here's another way to get a base64 encoded version of any binary:
希望這能像對我一樣幫助其他人.
Hope this helps others as it did for me.
這篇關于使用 Javascript 檢索二進制文件內容,base64 對其進行編碼并使用 Python 對其進行反向解碼的文章就介紹到這了,希望我們推薦的答案對大家有所幫助,也希望大家多多支持html5模板網!