How can you strip non-ASCII characters from a string? (in C#)

Question

How can you strip non-ASCII characters from a string? (in C#)

Answer 1

Inspired by philcruz's Regular Expression solution, I've made a pure LINQ 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 source)
{
    var buffer = new StringBuilder();
    foreach (var c in source)
        buffer.Append(c);
    return buffer.ToString();
}

This is untested code.