C# string comparison ignoring spaces, carriage return or line breaks

Question

How can I compare 2 strings in C# ignoring the case, spaces and any line-breaks. I also need to check if both strings are null then they are marked as same.

Thanks!<

Answer 1

An approach not optimized for performance, but for completeness.

• normalizes null
• normalizes unicode, combining characters, diacritics
• normalizes new lines
• normalizes white space
• normalizes casing

code snippet:

public static class StringHelper
{
    public static bool AreEquivalent(string source, string target)
    {
        if (source == null) return target == null;
        if (target == null) return false;
        var normForm1 = Normalize(source);
        var normForm2 = Normalize(target);
        return string.Equals(normForm1, normForm2);
    }

    private static string Normalize(string value)
    {
        Debug.Assert(value != null);
        // normalize unicode, combining characters, diacritics
        value = value.Normalize(NormalizationForm.FormC);
        // normalize new lines to white space
        value = value.Replace("\r\n", "\n").Replace("\r", "\n");
        // normalize white space
        value = Regex.Replace(value, @"\s", string.Empty);
        // normalize casing
        return value.ToLowerInvariant();
    }
}