C# IndexOf IgnoreCase Special Chars

Question

How can I do a indexOf Case Insensite with special chars? I need to search for the word "benefícios", and I want IndexOf to find it even if I don't use the special char on "i"

This way I can't find it:

string str = "candidatar-se a benefícios";
string word = "beneficio";
str.IndexOf(word, StringComparison.OrdinalIgnoreCase)

But with this one I can:

string str = "candidatar-se a benefícios exclusivos";
string word = "benefício";
str.IndexOf(word, StringComparison.OrdinalIgnoreCase)

Thanks

Convert the special characters in the source string to your desired charset (ASCII?) *before* searching with `IndexOf`. — zzzzBov, May 08 '15 at 15:00

score 5 · Accepted Answer · answered May 08 '15 at 15:03

Use the CompareInfo of the relevant culture and use CompareOptions.IgnoreNonSpace:

string str = "candidatar-se a benefícios";
string word = "beneficio";

var compareInfo = CultureInfo.InvariantCulture.CompareInfo;
compareInfo.IndexOf(str, word, CompareOptions.IgnoreNonSpace);

You can also combine other compare options - if you wanted to ignore case as well, for example, use CompareOptions.IgnoreNonSpace | CompareOptions.IgnoreCase.

The documentation for IndexOf and CompareOptions may be of some help.

See the notes below the code re combining `CompareOptions`. – Charles Mager May 08 '15 at 15:18 — Charles Mager, May 08 '15 at 15:18

score 2 · Answer 2 · edited May 23 '17 at 10:24

2

Take a look at this question

The second answer seems to be exactly what you are looking for.

edited May 23 '17 at 10:24

Community

1
1

answered May 08 '15 at 15:02

Vlad274

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score 1 · Answer 3 · answered May 08 '15 at 15:03

you can have it two ways:

either you use CharUnicodeInfo.GetUnicodeCategory for diacritic marks:

static string RemoveDiacritics(string text) 
{
    var normalizedString = text.Normalize(NormalizationForm.FormD);
    var stringBuilder = new StringBuilder();

    foreach (var c in normalizedString)
    {
        var unicodeCategory = CharUnicodeInfo.GetUnicodeCategory(c);
        if (unicodeCategory != UnicodeCategory.NonSpacingMark)
        {
            stringBuilder.Append(c);
        }
    }

    return stringBuilder.ToString().Normalize(NormalizationForm.FormC);

}

or you use the UnidecodeSharpFork https://bitbucket.org/DimaStefantsov/unidecodesharpfork

   var result = "Test æ".Unidecode();
   Console.WriteLine(result) // Prints Test ae

C# IndexOf IgnoreCase Special Chars

3 Answers3

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