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CSharp · Console

/Program.cs

using System;
using System.Text.RegularExpressions;
					
public class Program
{
	public static void Main()
	{
		string text = "<p>This is a \"wonderful long text\". \"Another wonderful ong text\"</p> At least it should be. Here we have a <a href=\"http://wwww.site-to-nowhere.com\" target=\"_blank\">link</a>";
        Console.WriteLine(text);

        Regex rx = new Regex("<.*?>");

        string result = rx.Replace(text, new MatchEvaluator(ReplaceLink)).Replace("\"", "&" + "quot;");
		Console.WriteLine(result);
	}
	
	static string ReplaceLink(Match m)
    {
        return m.ToString().Replace("\"", "'");
    }
	
}