String replace diacritics in C#

Question

I'd like to use this method to create user-friendly URL. Because my site is in Croatian, there are characters that I wouldn't like to strip but replace them with another. For example, this string:

ŠĐĆŽ šđčćž

needs to be:

sdccz-sdccz

So, I would like to make two arrays, one that will contain characters that are to be replaced and other array with replacement characters:

string[] character = { "Š", "Đ", "Č", "Ć", "Ž", "š", "đ", "č", "ć", "ž" };
string[] characterReplace = { "s", "d", "c", "c", "z", "s", "d", "c", "c", "z" };

Finally, this two arrays should be use in some method that will take string, find matches and replace them. In php I used preg_replace function to deal with this. In C# this doesn't work:

s = Regex.Replace(s, character, characterReplace);

Would appreciate if someone could help.

See http://stackoverflow.com/questions/2393887/how-to-replace-special-characters-with-their-equivalent-such-as-a-for-a — Mark Byers, Apr 02 '10 at 13:16

Josh Stodola · Answer 1 · 2010-04-02T13:46:54.540

17

Jon Skeet mentioned the following code on a newsgroup...

static string RemoveAccents (string input)
{
    string normalized = input.Normalize(NormalizationForm.FormKD);
    Encoding removal = Encoding.GetEncoding(Encoding.ASCII.CodePage,
                                            new EncoderReplacementFallback(""),
                                            new DecoderReplacementFallback(""));
    byte[] bytes = removal.GetBytes(normalized);
    return Encoding.ASCII.GetString(bytes);
}

EDIT

Maybe I am crazy, but I just ran the following...

Dim Input As String = "ŠĐĆŽ-šđčćž"
Dim Builder As New StringBuilder()

For Each Chr As Char In Input
    Builder.Append(Chr)
Next

Console.Write(Builder.ToString())

And the output was SDCZ-sdccz

edited Apr 02 '10 at 13:46

answered Apr 02 '10 at 13:22

Josh Stodola

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This removes the Đ completely. – Mark Byers Apr 02 '10 at 13:27
@Mark You are right, but see my edit, it is somewhat unbelievable – Josh Stodola Apr 02 '10 at 13:47
hmm I tried that VB.NET code locally and I get the original string. – Ahmad Mageed Apr 02 '10 at 14:03
@Ahmad I bet it is somehow related to localization settings. I must say that I was daunted when it produced the desired output. – Josh Stodola Apr 02 '10 at 14:40
This also removes "ł" (polish). – user1713059 May 15 '19 at 16:07
Id doesn't work for 'ł' and '€' characters – ahaw Nov 13 '20 at 06:49

score 16 · Accepted Answer · edited May 23 '17 at 11:53

16

It seems you want to strip off diacritics and leave the base character. I'd recommend Ben Lings's solution here for this:

string input = "ŠĐĆŽ šđčćž";
string decomposed = input.Normalize(NormalizationForm.FormD);
char[] filtered = decomposed
    .Where(c => char.GetUnicodeCategory(c) != UnicodeCategory.NonSpacingMark)
    .ToArray();
string newString = new String(filtered);

Edit: Slight problem! It doesn't work for the Đ. The result is:

SĐCZ sđccz

edited May 23 '17 at 11:53

Community

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answered Apr 02 '10 at 13:18

Mark Byers

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I get following error: 'string' does not contain a definition for 'Normalise' and no extension method 'Normalise' accepting a first argument of type 'string' could be found (are you missing a using directive or an assembly reference?) – ilija veselica Apr 02 '10 at 13:24
@ile: Apparently there was an error in the solution I copied this from. I have fixed it now. Unfortunately though this method fails for Đ, so either you will have to handle that case specially, or just do it the way you originally suggested. – Mark Byers Apr 02 '10 at 13:25
I see... but this is very simple solution and I will use this and use special method to replace Đ and đ. Thanks! – ilija veselica Apr 02 '10 at 13:30

score 0 · Answer 3 · answered Apr 02 '10 at 13:40

A dictionary would be a logical solution to this...

Dictionary<char, char> AccentEquivelants = new Dictionary<char, char>();
AccentEquivelants.Add('Š', 's');
//...add other equivelents

string inputstring = "";
StringBuilder FixedString = new StringBuilder(inputstring);
for (int i = 0; i < FixedString.Length; i++)
    if (AccentEquivelants.ContainsKey(FixedString[i]))
        FixedString[i] = AccentEquivelants[FixedString[i]];
return FixedString.ToString();

You need to use a StringBuilder when doing string operations like this because strings in C# are immutable, so changing a character at a time will create several string objects in memory, whereas StringBuilders are mutable and do not have this drawback.

But character arrays are not. Create a character array and modify the values in it. — Timothy Baldridge, Apr 02 '10 at 13:45

String replace diacritics in C#

3 Answers3

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