Powershell function: Convert-DiacriticCharacters

We needed to normalize diacritics characters to standard English characters. Diacritic characters are extended or accented characters to the modern latin basic alphabet i.e. A-Z. Scandinavian diacritics such as å,ä and ö should in normalized form become a, a and o. Spanish diacritics should such as ó, ñ and ç should be normalized to o, n and c. The unicode normalization forms can be found here and the normalization charts here.

 

Since we mostly use powershell these days, I've written a nice Convert-DiacriticCharacters powershell function.

 

function Convert-DiacriticCharacters {
    param(

        [string]$inputString

    )

    [string]$formD = $inputString.Normalize(

            [System.text.NormalizationForm]::FormD

    )

    $stringBuilder = new-object System.Text.StringBuilder

    for ($i = 0; $i -lt $formD.Length; $i++){

        $unicodeCategory = [System.Globalization.CharUnicodeInfo]::GetUnicodeCategory($formD[$i])

        $nonSPacingMark = [System.Globalization.UnicodeCategory]::NonSpacingMark

        if($unicodeCategory -ne $nonSPacingMark){

            $stringBuilder.Append($formD[$i]) | out-null

        }

    }
    $stringBuilder.ToString().Normalize([System.text.NormalizationForm]::FormC)
}

 

The resulting function will convert diacritics in the follwoing way:

 

    PS C:\> Convert-DiacriticCharacters "Ångström"
    Angstrom
    PS C:\> Convert-DiacriticCharacters "Ó señor"
    O senor

In our Identity Management projects we encounter issues like these as soon as we deal with global companies. Many systems can't handle Unicode characters or diacritic characters from different non-unicode code pages, in our case we were writing some code to provision users in RACF and RACF couldn't handle the characters.