What is the best way to remove non-ASCII characters from a string? (written in C#)

Problem

What is the best way to remove non-ASCII characters from a string? (written in C#)

Asked by philcruz

Solution #1

string s = "søme string";
s = Regex.Replace(s, @"[^\u0000-\u007F]+", string.Empty);

Answered by philcruz

Solution #2

Here’s a solution that doesn’t use regular expressions and is entirely written in.NET:

string inputString = "Räksmörgås";
string asAscii = Encoding.ASCII.GetString(
    Encoding.Convert(
        Encoding.UTF8,
        Encoding.GetEncoding(
            Encoding.ASCII.EncodingName,
            new EncoderReplacementFallback(string.Empty),
            new DecoderExceptionFallback()
            ),
        Encoding.UTF8.GetBytes(inputString)
    )
);

It may appear complicated, but it should be simple to use. It converts a string using the.NET ASCII encoding. Because it can represent any of the original characters, UTF8 is used during the conversion. Any non-ASCII character is converted to an empty string using an EncoderReplacementFallback.

Answered by bzlm

Solution #3

MonsCamus, I assume, meant:

parsememo = Regex.Replace(parsememo, @"[^\u0020-\u007E]", string.Empty);

Answered by Josh

Solution #4

Take a look at this question if you don’t want to strip but rather convert latin accented to non-accented characters: What is the best way to convert 8-bit characters to 7-bit characters? (For example, Ü to U)

Answered by sinelaw

Solution #5

I’ve created a pure LINQ solution, inspired by philcruz’s Regular Expression solution.

public static string PureAscii(this string source, char nil = ' ')
{
    var min = '\u0000';
    var max = '\u007F';
    return source.Select(c => c < min ? nil : c > max ? nil : c).ToText();
}

public static string ToText(this IEnumerable<char> source)
{
    var buffer = new StringBuilder();
    foreach (var c in source)
        buffer.Append(c);
    return buffer.ToString();
}

This code has not been tested.

Answered by Bent Rasmussen

Post is based on https://stackoverflow.com/questions/123336/how-can-you-strip-non-ascii-characters-from-a-string-in-c