Source code for htmlescape.cs

using System;

using System.IO;

using System.Linq;

using System.Net;

namespace RobvanderWoude

{

	internal class HTMLEscape

	{

		static readonly string progver = "1.01";

		static int Main( string[] args )

		{

			int rc = 0;

			int argumentscount = args.Length;

			if ( Console.IsInputRedirected )

			{

				argumentscount++;

			}

			if ( argumentscount != 1 || args.Contains( "/?" ) )

			{

				return ShowHelp( );

			}

			string unescapedtext = string.Empty;

			if ( Console.IsInputRedirected )

			{

				unescapedtext = Console.In.ReadToEnd( );

			}

			else if ( File.Exists( args[0] ) )

			{

				unescapedtext= File.ReadAllText( args[0] );

			}

			else

			{

				unescapedtext = args[0];

			}

			string escapedtext = WebUtility.HtmlEncode( unescapedtext );

			escapedtext = ConvertHTMLEntities( escapedtext );

			Console.Write( escapedtext );

			return rc;

		}

		static string ConvertHTMLEntities( string input )

		{

			string output = input.Replace( "'", "'" );

			output = output.Replace( "À", "À" );

			output = output.Replace( "&3193;", "Á" );

			output = output.Replace( "Â", "Â" );

			output = output.Replace( "Ã", "Ã" );

			output = output.Replace( "Ä", "Ä" );

			output = output.Replace( "Å", "Å" );

			output = output.Replace( "Æ", "Æ" );

			output = output.Replace( "Ç", "Ç" );

			output = output.Replace( "È", "È" );

			output = output.Replace( "É", "É" );

			output = output.Replace( "Ê", "Ê" );

			output = output.Replace( "Ë", "Ë" );

			output = output.Replace( "Ì", "Ì" );

			output = output.Replace( "Í", "Í" );

			output = output.Replace( "Î", "Î" );

			output = output.Replace( "Ï", "Ï" );

			output = output.Replace( "Ð", "Ð" );

			output = output.Replace( "Ñ", "Ñ" );

			output = output.Replace( "Ò", "Ò" );

			output = output.Replace( "Ó", "Ó" );

			output = output.Replace( "Ô", "Ô" );

			output = output.Replace( "Õ", "Õ" );

			output = output.Replace( "Ö", "Ö" );

			output = output.Replace( "Ø", "Ø" );

			output = output.Replace( "Ù", "Ù" );

			output = output.Replace( "Ú", "Ú" );

			output = output.Replace( "Û", "Û" );

			output = output.Replace( "Ü", "Ü" );

			output = output.Replace( "Ý", "Ý" );

			output = output.Replace( "Þ", "Þ" );

			output = output.Replace( "ß", "ß" );

			output = output.Replace( "à", "à" );

			output = output.Replace( "á", "á" );

			output = output.Replace( "â", "â" );

			output = output.Replace( "ã", "ã" );

			output = output.Replace( "ä", "ä" );

			output = output.Replace( "å", "å" );

			output = output.Replace( "æ", "æ" );

			output = output.Replace( "ç", "ç" );

			output = output.Replace( "è", "è" );

			output = output.Replace( "é", "é" );

			output = output.Replace( "ê", "ê" );

			output = output.Replace( "ë", "ë" );

			output = output.Replace( "ì", "ì" );

			output = output.Replace( "í", "í" );

			output = output.Replace( "î", "î" );

			output = output.Replace( "ï", "ï" );

			output = output.Replace( "ð", "ð" );

			output = output.Replace( "ñ", "ñ" );

			output = output.Replace( "ò", "ò" );

			output = output.Replace( "ó", "ó" );

			output = output.Replace( "ô", "ô" );

			output = output.Replace( "õ", "õ" );

			output = output.Replace( "ö", "ö" );

			output = output.Replace( "ø", "ø" );

			output = output.Replace( "ù", "ù" );

			output = output.Replace( "ú", "ú" );

			output = output.Replace( "û", "û" );

			output = output.Replace( "ü", "ü" );

			output = output.Replace( "ý", "ý" );

			output = output.Replace( "þ", "þ" );

			output = output.Replace( "ÿ", "ÿ" );

			return output;

		}

		public static int ShowHelp( string errorMessage = "" )

		{

			#region Help Text

			/*

			HTMLEscape,  Version 1.00

			Display HTML-escaped input string in console

			Usage:  HTMLESCAPE  textfile

			   or:  HTMLESCAPE  unescapedstring

			   or:  some_program | HTMLESCAPE

			Where:  textfile         file containing text to be escaped

			        unescapedstring  string to be escaped

			        some_program     program whose output is to be escaped

			Note:   Exit code ("errorlevel") -1 in case of errors, otherwise 0.

			Written by Rob van der Woude

			https://www.robvanderwoude.com

			*/

			#endregion Help Text

			#region Error Message

			if ( !string.IsNullOrWhiteSpace( errorMessage ) )

			{

				Console.Error.WriteLine( );

				Console.ForegroundColor = ConsoleColor.Red;

				Console.Error.Write( "ERROR: " );

				Console.ForegroundColor = ConsoleColor.White;

				Console.Error.WriteLine( errorMessage );

				Console.ResetColor( );

			}

			#endregion Error Message

			#region Display Help

			Console.Error.WriteLine( );

			Console.Error.WriteLine( "HTMLEscape,  Version {0}", progver );

			Console.Error.WriteLine( "Display HTML-escaped input string in console" );

			Console.Error.WriteLine( );

			Console.Error.Write( "Usage:  " );

			Console.ForegroundColor = ConsoleColor.White;

			Console.Error.WriteLine( "HTMLESCAPE  textfile" );

			Console.ResetColor( );

			Console.Error.WriteLine( );

			Console.Error.Write( "   or:  " );

			Console.ForegroundColor = ConsoleColor.White;

			Console.Error.WriteLine( "HTMLESCAPE  unescapedstring" );

			Console.ResetColor( );

			Console.Error.WriteLine( );

			Console.Error.Write( "   or:  " );

			Console.ForegroundColor = ConsoleColor.White;

			Console.Error.WriteLine( "some_program | HTMLESCAPE" );

			Console.ResetColor( );

			Console.Error.WriteLine( );

			Console.Error.Write( "Where:  " );

			Console.ForegroundColor = ConsoleColor.White;

			Console.Error.Write( "textfile" );

			Console.ResetColor( );

			Console.Error.WriteLine( "         file containing text to be escaped" );

			Console.ForegroundColor = ConsoleColor.White;

			Console.Error.Write( "        unescapedstring" );

			Console.ResetColor( );

			Console.Error.WriteLine( "  string to be escaped" );

			Console.ForegroundColor = ConsoleColor.White;

			Console.Error.Write( "        some_program" );

			Console.ResetColor( );

			Console.Error.WriteLine( "     program whose output is to be escaped" );

			Console.Error.WriteLine( );

			Console.Error.WriteLine( "Note:   Exit code (\"errorlevel\") -1 in case of errors, otherwise 0." );

			Console.Error.WriteLine( );

			Console.Error.WriteLine( "Written by Rob van der Woude" );

			Console.Error.WriteLine( "https://www.robvanderwoude.com" );

			#endregion Display Help

			return -1;

		}

	}

}