Remove accents in string except "ñ"

Question

I have the following example code:

var inputString = "ñaáme";
inputString = inputString.Replace('ñ', '\u00F1');
var normalizedString = inputString.Normalize(NormalizationForm.FormD);
var result = Regex.Replace(normalizedString, @"[^ñÑa-zA-Z0-9\s]*", string.Empty);
return result.Replace('\u00F1', 'ñ'); // naame :(

I need to normalize the text without removing the "ñ"s

I followed this example But it's for Java and it has not worked for me

I want your result to be: "ñaame".

Answer 1

You may match any Unicode letter other than your specific letter ñ and ASCII letters (that do not need normalization) with (?i)[\p{L}-[ña-z]]+ regex and normalize it. Then, also remove any combining marks from the string.

Use

var inputString = "ñaáme";
var result = string.Concat(Regex.Replace(inputString, @"(?i)[\p{L}-[ña-z]]+", m => 
        m.Value.Normalize(NormalizationForm.FormD)
    )
    .Where(c => CharUnicodeInfo.GetUnicodeCategory(c) != UnicodeCategory.NonSpacingMark));
Console.Write(result);

See the C# demo

Pattern description

• (?i) - ignore case modifier
• [ - start of a character class
  • \p{L} - any Unicode letter
  • -[ - other than
    • ña-z - ñ and ASCII letters
  • ] - end of the subtraction class
• ]+ - 1 or more occurrences.