ANSI Encoding implementation for Silverlight

Question

I need Encoding implementation of some codepage in my Silverlight app. Particularly I need to read non-Engligh file names from zip-archive (being opened Application.GetResourceStream).

Silverlight contains only Unicode encodings (Encoding.UTF8, Encoding.Unicode, Encoding.BigEndianUnicode). Encoding.GetEncoding throws exception for other encoding names.

But I need Encoding class implementation for some ANSI codepage (866 particularly). On desktop I'd get it via Encoding.GetEncoding(866).

Where can I get the simplest implementation?

p.s. I understand that the question hardly relates Silverlight, but without mentioning it I'll be suggested to use Encoding.GetEncoding I guess..

@Bala R: thanks! It's turned to be pretty easy. I wish you answered as "answer" not comment. — Shrike, May 03 '11 at 21:42
@tchrist That means "ANSI code pages" or "Windows code pages". See http://en.wikipedia.org/wiki/Windows_code_page — Shrike, May 06 '11 at 10:27

score 0 · Accepted Answer · answered May 03 '11 at 21:43

0

From http://en.wikipedia.org/wiki/Code_page_866 you can build a map and convert your stuff to UTF-8.

answered May 03 '11 at 21:43

Bala R

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score 0 · Answer 2 · answered May 03 '11 at 21:48

Thanks to @Bala_R, i get 866 codepage and write:

    private byte[] translateInto866(string fileName)
    {
        const byte startCode1 = 128;        // А, 0410
        const byte startCode2 = 224;        // р, 0440

        var result = new byte[fileName.Length];
        int i = 0;
        foreach (char c in fileName)
        {
            if (c >= 'А' && c <= 'п')
            {
                result[i] = (byte)(((byte)(c - 'А')) + startCode1);
            }
            else if (c > 'п' && c <= 'я')
            {
                result[i] = (byte)(((byte)(c - 'р')) + startCode2);
            }
            else
            {
                result[i] = (byte) c;
            }
            i++;
        }
        return result;
    }

Now we only need to understand what codepage was used to encode file name. We have its unicode representation in manifest and a representation in some encoding inside zip. It should be not very hard to find appropriate encoding. But in my case I just know that if it's not utf8 then it's 866.

ANSI Encoding implementation for Silverlight

2 Answers2