1、unescape实现代码
using System;
using System.Collections.Generic;
using System.Globalization;
using System.IO;
using System.Linq;
using System.Text;
namespace StringUnescape
{
public static class StringUnescape
{
static SortedDictionary<string, char> entities = new SortedDictionary<string, char>(StringComparer.Ordinal);
public static SortedDictionary<string, char> Entities { get { return entities; } }
static StringUnescape()
{
entities.Add("nbsp", '\u00A0');
entities.Add("iexcl", '\u00A1');
entities.Add("cent", '\u00A2');
entities.Add("pound", '\u00A3');
entities.Add("curren", '\u00A4');
entities.Add("yen", '\u00A5');
entities.Add("brvbar", '\u00A6');
entities.Add("sect", '\u00A7');
entities.Add("uml", '\u00A8');
entities.Add("copy", '\u00A9');
entities.Add("ordf", '\u00AA');
entities.Add("laquo", '\u00AB');
entities.Add("not", '\u00AC');
entities.Add("shy", '\u00AD');
entities.Add("reg", '\u00AE');
entities.Add("macr", '\u00AF');
entities.Add("deg", '\u00B0');
entities.Add("plusmn", '\u00B1');
entities.Add("sup2", '\u00B2');
entities.Add("sup3", '\u00B3');
entities.Add("acute", '\u00B4');
entities.Add("micro", '\u00B5');
entities.Add("para", '\u00B6');
entities.Add("middot", '\u00B7');
entities.Add("cedil", '\u00B8');
entities.Add("sup1", '\u00B9');
entities.Add("ordm", '\u00BA');
entities.Add("raquo", '\u00BB');
entities.Add("frac14", '\u00BC');
entities.Add("frac12", '\u00BD');
entities.Add("frac34", '\u00BE');
entities.Add("iquest", '\u00BF');
entities.Add("Agrave", '\u00C0');
entities.Add("Aacute", '\u00C1');
entities.Add("Acirc", '\u00C2');
entities.Add("Atilde", '\u00C3');
entities.Add("Auml", '\u00C4');
entities.Add("Aring", '\u00C5');
entities.Add("AElig", '\u00C6');
entities.Add("Ccedil", '\u00C7');
entities.Add("Egrave", '\u00C8');
entities.Add("Eacute", '\u00C9');
entities.Add("Ecirc", '\u00CA');
entities.Add("Euml", '\u00CB');
entities.Add("Igrave", '\u00CC');
entities.Add("Iacute", '\u00CD');
entities.Add("Icirc", '\u00CE');
entities.Add("Iuml", '\u00CF');
entities.Add("ETH", '\u00D0');
entities.Add("Ntilde", '\u00D1');
entities.Add("Ograve", '\u00D2');
entities.Add("Oacute", '\u00D3');
entities.Add("Ocirc", '\u00D4');
entities.Add("Otilde", '\u00D5');
entities.Add("Ouml", '\u00D6');
entities.Add("times", '\u00D7');
entities.Add("Oslash", '\u00D8');
entities.Add("Ugrave", '\u00D9');
entities.Add("Uacute", '\u00DA');
entities.Add("Ucirc", '\u00DB');
entities.Add("Uuml", '\u00DC');
entities.Add("Yacute", '\u00DD');
entities.Add("THORN", '\u00DE');
entities.Add("szlig", '\u00DF');
entities.Add("agrave", '\u00E0');
entities.Add("aacute", '\u00E1');
entities.Add("acirc", '\u00E2');
entities.Add("atilde", '\u00E3');
entities.Add("auml", '\u00E4');
entities.Add("aring", '\u00E5');
entities.Add("aelig", '\u00E6');
entities.Add("ccedil", '\u00E7');
entities.Add("egrave", '\u00E8');
entities.Add("eacute", '\u00E9');
entities.Add("ecirc", '\u00EA');
entities.Add("euml", '\u00EB');
entities.Add("igrave", '\u00EC');
entities.Add("iacute", '\u00ED');
entities.Add("icirc", '\u00EE');
entities.Add("iuml", '\u00EF');
entities.Add("eth", '\u00F0');
entities.Add("ntilde", '\u00F1');
entities.Add("ograve", '\u00F2');
entities.Add("oacute", '\u00F3');
entities.Add("ocirc", '\u00F4');
entities.Add("otilde", '\u00F5');
entities.Add("ouml", '\u00F6');
entities.Add("divide", '\u00F7');
entities.Add("oslash", '\u00F8');
entities.Add("ugrave", '\u00F9');
entities.Add("uacute", '\u00FA');
entities.Add("ucirc", '\u00FB');
entities.Add("uuml", '\u00FC');
entities.Add("yacute", '\u00FD');
entities.Add("thorn", '\u00FE');
entities.Add("yuml", '\u00FF');
entities.Add("fnof", '\u0192');
entities.Add("Alpha", '\u0391');
entities.Add("Beta", '\u0392');
entities.Add("Gamma", '\u0393');
entities.Add("Delta", '\u0394');
entities.Add("Epsilon", '\u0395');
entities.Add("Zeta", '\u0396');
entities.Add("Eta", '\u0397');
entities.Add("Theta", '\u0398');
entities.Add("Iota", '\u0399');
entities.Add("Kappa", '\u039A');
entities.Add("Lambda", '\u039B');
entities.Add("Mu", '\u039C');
entities.Add("Nu", '\u039D');
entities.Add("Xi", '\u039E');
entities.Add("Omicron", '\u039F');
entities.Add("Pi", '\u03A0');
entities.Add("Rho", '\u03A1');
entities.Add("Sigma", '\u03A3');
entities.Add("Tau", '\u03A4');
entities.Add("Upsilon", '\u03A5');
entities.Add("Phi", '\u03A6');
entities.Add("Chi", '\u03A7');
entities.Add("Psi", '\u03A8');
entities.Add("Omega", '\u03A9');
entities.Add("alpha", '\u03B1');
entities.Add("beta", '\u03B2');
entities.Add("gamma", '\u03B3');
entities.Add("delta", '\u03B4');
entities.Add("epsilon", '\u03B5');
entities.Add("zeta", '\u03B6');
entities.Add("eta", '\u03B7');
entities.Add("theta", '\u03B8');
entities.Add("iota", '\u03B9');
entities.Add("kappa", '\u03BA');
entities.Add("lambda", '\u03BB');
entities.Add("mu", '\u03BC');
entities.Add("nu", '\u03BD');
entities.Add("xi", '\u03BE');
entities.Add("omicron", '\u03BF');
entities.Add("pi", '\u03C0');
entities.Add("rho", '\u03C1');
entities.Add("sigmaf", '\u03C2');
entities.Add("sigma", '\u03C3');
entities.Add("tau", '\u03C4');
entities.Add("upsilon", '\u03C5');
entities.Add("phi", '\u03C6');
entities.Add("chi", '\u03C7');
entities.Add("psi", '\u03C8');
entities.Add("omega", '\u03C9');
entities.Add("thetasym", '\u03D1');
entities.Add("upsih", '\u03D2');
entities.Add("piv", '\u03D6');
entities.Add("bull", '\u2022');
entities.Add("hellip", '\u2026');
entities.Add("prime", '\u2032');
entities.Add("Prime", '\u2033');
entities.Add("oline", '\u203E');
entities.Add("frasl", '\u2044');
entities.Add("weierp", '\u2118');
entities.Add("image", '\u2111');
entities.Add("real", '\u211C');
entities.Add("trade", '\u2122');
entities.Add("alefsym", '\u2135');
entities.Add("larr", '\u2190');
entities.Add("uarr", '\u2191');
entities.Add("rarr", '\u2192');
entities.Add("darr", '\u2193');
entities.Add("harr", '\u2194');
entities.Add("crarr", '\u21B5');
entities.Add("lArr", '\u21D0');
entities.Add("uArr", '\u21D1');
entities.Add("rArr", '\u21D2');
entities.Add("dArr", '\u21D3');
entities.Add("hArr", '\u21D4');
entities.Add("forall", '\u2200');
entities.Add("part", '\u2202');
entities.Add("exist", '\u2203');
entities.Add("empty", '\u2205');
entities.Add("nabla", '\u2207');
entities.Add("isin", '\u2208');
entities.Add("notin", '\u2209');
entities.Add("ni", '\u220B');
entities.Add("prod", '\u220F');
entities.Add("sum", '\u2211');
entities.Add("minus", '\u2212');
entities.Add("lowast", '\u2217');
entities.Add("radic", '\u221A');
entities.Add("prop", '\u221D');
entities.Add("infin", '\u221E');
entities.Add("ang", '\u2220');
entities.Add("and", '\u2227');
entities.Add("or", '\u2228');
entities.Add("cap", '\u2229');
entities.Add("cup", '\u222A');
entities.Add("int", '\u222B');
entities.Add("there4", '\u2234');
entities.Add("sim", '\u223C');
entities.Add("cong", '\u2245');
entities.Add("asymp", '\u2248');
entities.Add("ne", '\u2260');
entities.Add("equiv", '\u2261');
entities.Add("le", '\u2264');
entities.Add("ge", '\u2265');
entities.Add("sub", '\u2282');
entities.Add("sup", '\u2283');
entities.Add("nsub", '\u2284');
entities.Add("sube", '\u2286');
entities.Add("supe", '\u2287');
entities.Add("oplus", '\u2295');
entities.Add("otimes", '\u2297');
entities.Add("perp", '\u22A5');
entities.Add("sdot", '\u22C5');
entities.Add("lceil", '\u2308');
entities.Add("rceil", '\u2309');
entities.Add("lfloor", '\u230A');
entities.Add("rfloor", '\u230B');
entities.Add("lang", '\u2329');
entities.Add("rang", '\u232A');
entities.Add("loz", '\u25CA');
entities.Add("spades", '\u2660');
entities.Add("clubs", '\u2663');
entities.Add("hearts", '\u2665');
entities.Add("diams", '\u2666');
entities.Add("quot", '\u0022');
entities.Add("amp", '\u0026');
entities.Add("lt", '\u003C');
entities.Add("gt", '\u003E');
entities.Add("OElig", '\u0152');
entities.Add("oelig", '\u0153');
entities.Add("Scaron", '\u0160');
entities.Add("scaron", '\u0161');
entities.Add("Yuml", '\u0178');
entities.Add("circ", '\u02C6');
entities.Add("tilde", '\u02DC');
entities.Add("ensp", '\u2002');
entities.Add("emsp", '\u2003');
entities.Add("thinsp", '\u2009');
entities.Add("zwnj", '\u200C');
entities.Add("zwj", '\u200D');
entities.Add("lrm", '\u200E');
entities.Add("rlm", '\u200F');
entities.Add("ndash", '\u2013');
entities.Add("mdash", '\u2014');
entities.Add("lsquo", '\u2018');
entities.Add("rsquo", '\u2019');
entities.Add("sbquo", '\u201A');
entities.Add("ldquo", '\u201C');
entities.Add("rdquo", '\u201D');
entities.Add("bdquo", '\u201E');
entities.Add("dagger", '\u2020');
entities.Add("Dagger", '\u2021');
entities.Add("permil", '\u2030');
entities.Add("lsaquo", '\u2039');
entities.Add("rsaquo", '\u203A');
entities.Add("euro", '\u20AC');
}
public static string Unescape(this string s)
{
if (s == null)
return null;
if (s.Length == 0)
return String.Empty;
if (s.IndexOf('&') == -1)
return s;
StringBuilder rawEntity = new StringBuilder();
StringBuilder entity = new StringBuilder();
StringBuilder output = new StringBuilder();
int len = s.Length;
// 0 -> nothing,
// 1 -> right after '&'
// 2 -> between '&' and ';' but no '#'
// 3 -> '#' found after '&' and getting numbers
int state = 0;
int number = 0;
bool is_hex_value = false;
bool have_trailing_digits = false;
for (int i = 0; i < len; i++)
{
char c = s[i];
if (state == 0)
{
if (c == '&')
{
entity.Append(c);
rawEntity.Append(c);
state = 1;
}
else
{
output.Append(c);
}
continue;
}
if (c == '&')
{
state = 1;
if (have_trailing_digits)
{
entity.Append(number.ToString(CultureInfo.InvariantCulture));
have_trailing_digits = false;
}
output.Append(entity.ToString());
entity.Length = 0;
entity.Append('&');
continue;
}
if (state == 1)
{
if (c == ';')
{
state = 0;
output.Append(entity.ToString());
output.Append(c);
entity.Length = 0;
}
else
{
number = 0;
is_hex_value = false;
if (c != '#')
{
state = 2;
}
else
{
state = 3;
}
entity.Append(c);
rawEntity.Append(c);
}
}
else if (state == 2)
{
entity.Append(c);
if (c == ';')
{
string key = entity.ToString();
if (key.Length > 1 && Entities.ContainsKey(key.Substring(1, key.Length - 2)))
key = Entities[key.Substring(1, key.Length - 2)].ToString();
output.Append(key);
state = 0;
entity.Length = 0;
rawEntity.Length = 0;
}
}
else if (state == 3)
{
if (c == ';')
{
if (number == 0)
output.Append(rawEntity.ToString() + ";");
else
if (number > 65535)
{
output.Append("&#");
output.Append(number.ToString(CultureInfo.InvariantCulture));
output.Append(";");
}
else
{
output.Append((char)number);
}
state = 0;
entity.Length = 0;
rawEntity.Length = 0;
have_trailing_digits = false;
}
else if (is_hex_value && Uri.IsHexDigit(c))
{
number = number * 16 + Uri.FromHex(c);
have_trailing_digits = true;
rawEntity.Append(c);
}
else if (Char.IsDigit(c))
{
number = number * 10 + ((int)c - '0');
have_trailing_digits = true;
rawEntity.Append(c);
}
else if (number == 0 && (c == 'x' || c == 'X'))
{
is_hex_value = true;
rawEntity.Append(c);
}
else
{
state = 2;
if (have_trailing_digits)
{
entity.Append(number.ToString(CultureInfo.InvariantCulture));
have_trailing_digits = false;
}
entity.Append(c);
}
}
}
if (entity.Length > 0)
{
output.Append(entity.ToString());
}
else if (have_trailing_digits)
{
output.Append(number.ToString(CultureInfo.InvariantCulture));
}
return output.ToString();
}
}
}
2、调用StringUnescape的Unescape扩展方法
扩展方法直接通过字符串.方法的方式调用。
string str = "红火干训、".Unescape()//红火干训、