How to decode a url with accents in C#

Question

I've been trying to decode %E9(é).

WebUtility.HtmlDecode("%E9")

doesn't work. It puts a ? sign instead of a é.

When I use `WebUtility.HtmlEncode("é")`, I get: `é`, not `%E9`. When I run `HtmlDecode("é");`, I get `é`. So I think `HtmlDecode` is not the method you're looking for. — Adam V, Sep 01 '15 at 18:46
The correct answer to this question is very dependent on where that url with accents is coming from. According to http://stackoverflow.com/questions/912811/what-is-the-proper-way-to-url-encode-unicode-characters the standard on the web is UTF-8, so trying to decode `"%E9"` (which doesn't represent a valid UTF-8 string) is a bit dodgy. — roeland, Sep 02 '15 at 05:46

score 6 · Accepted Answer · answered Sep 01 '15 at 18:59

6

I've tested this and found that HttpUtility.UrlDecode("%E9") returns question mark that You mentioned. It seems that it You have to manually specify appropriate encoding for this to work correctly with %E9 encoded value.

You can try:

HttpUtility.UrlDecode("%E9", System.Text.UnicodeEncoding.Default);

or

HttpUtility.UrlDecode("%E9", System.Text.UnicodeEncoding.UTF7);

Both should return the character decoded as You expected.

answered Sep 01 '15 at 18:59

Lukasz M

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UTF-7 is not used anywhere, it likely works in this case by coincidence. – roeland Sep 02 '15 at 05:42
It may be not popular, but this does not mean nobody uses it ;). – Lukasz M Sep 02 '15 at 19:27

score 3 · Answer 2 · answered Sep 01 '15 at 19:23

3

For Url decode, you should use UrlDecode instead of HtmlDecode. Also, you need to specify the encoding for this to work because the encoded value %E9 is not UTF-8 value, and by default UrlDecode returns string decoded using UTF-8.

Addition to Lukasz's answer, you can also use:

HttpUtility.UrlDecode("%E9", System.Text.Encoding.GetEncoding("iso-8859-1"));

answered Sep 01 '15 at 19:23

kofsp

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Perfect solution! – Xelit3 Apr 22 '21 at 10:26

How to decode a url with accents in C#

2 Answers2