Convert to punycode

using System.Globalization;

// convert to punycode
string unicode = project.Variables["text"].Value;
IdnMapping mapping = new IdnMapping();
string punnycode = mapping.GetAscii(unicode);
return punnycode;

// convert from punycode 
string unicode = project.Variables["text"].Value;
IdnMapping mapping = new IdnMapping();
string from_punycode = mapping.GetUnicode(unicode);
return from_punycode;

// convert to punycode
System.Globalization.IdnMapping idn = new System.Globalization.IdnMapping();
string url = "президент.рф";
string str = idn.GetAscii(url);
return str; // выведет «xn--d1abbgf6aiiy.xn--p1ai»

// convert from punycode
System.Globalization.IdnMapping idn = new System.Globalization.IdnMapping();
string url = "xn--d1abbgf6aiiy.xn--p1ai";
string str = idn.GetUnicode(url);
return str; //