using System;
using System.Text.RegularExpressions;
using System.Collections.Specialized;
 
public class Test
{
    public static void Main()
    {
    	var smilies = new OrderedDictionary
		{
		    {@">:(", "smile_angryx24"},  // Put this one first
		    {@":(", "smile_sadx24"},
		};
		string incomingtext = @"This is sad... :( But this makes me so angry!!! >:(";
		foreach (string smiley in smilies.Keys)
		{
		    var re = new Regex(@"(?<!(=""))" + Regex.Escape(smiley) + @"(?!(""))");
		                        // Second should be a negative lookahead ^^
		    if (re.IsMatch(incomingtext))
		    {
		        string m2 = re.Replace(incomingtext, "<img src=\"/Content/themes/mavi/img/custom/smiles/" + smilies[smiley] + ".png\"  alt=\"" + smiley + "\"/>");
		        incomingtext = m2;
		    }
		}
		Console.WriteLine(incomingtext);
    }
}

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