CharSanitizer.cs

using System.Collections.Generic;
using System.Linq;
using System.Text.RegularExpressions;

public static class CharSanitizer
{
	public static string CleanInput(string input)
	{
		return InputExpression.Replace(input, badChar => Replacements[badChar.Value]);
	}

	static readonly Dictionary<string, int[]> Map = new Dictionary<string, int[]>
	{
		{"'",	new[]{96,	8216,	8217,	8242,	769,	768}},
		{"\"",	new[]{8220,	8221,	8243,	12291}},
		{"-",	new[]{8208,	8211,	8212,	8722,	173,	8209,	8259}},
		{" ",	new[]{160,	8195,	8194}}
	};

	static readonly IDictionary<string, string> Replacements = Map
		.SelectMany(kvp => kvp.Value
			.Select(ch => new { BadCharString = ((char)ch).ToString(), CorrectString = kvp.Key }))
		.ToDictionary(p => p.BadCharString, p => p.CorrectString);

	static readonly Regex InputExpression =
		new Regex("[" + string.Join("", Replacements.Keys.ToArray()) + "]",
		RegexOptions.Compiled);
}