wktstreamtokenizer.cs

Sharp Map 用于制作GIS系统S harp Map 用于制作GIS系统S harp Map 用于制作GIS系统

// Copyright 2005, 2006 - Morten Nielsen (www.iter.dk)
//
// This file is part of SharpMap.
// SharpMap is free software; you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
// 
// SharpMap is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Lesser General Public License for more details.

// You should have received a copy of the GNU Lesser General Public License
// along with SharpMap; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA 

// SOURCECODE IS MODIFIED FROM ANOTHER WORK AND IS ORIGINALLY BASED ON GeoTools.NET:
/*
 *  Copyright (C) 2002 Urban Science Applications, Inc. 
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public
 *  License as published by the Free Software Foundation; either
 *  version 2.1 of the License, or (at your option) any later version.
 *
 *  This library is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 *  Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public
 *  License along with this library; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

#region Using
using System;
using System.IO;
using SharpMap.Converters.WellKnownText.IO;
#endregion

namespace SharpMap.Converters.WellKnownText
{
	/// <summary>
	/// Reads a stream of Well Known Text (wkt) string and returns a stream of tokens.
	/// </summary>
	internal class WktStreamTokenizer : StreamTokenizer
	{

		#region Constructors

		/// <summary>
		/// Initializes a new instance of the WktStreamTokenizer class.
		/// </summary>
		/// <remarks>The WktStreamTokenizer class ais in reading WKT streams.</remarks>
		/// <param name="reader">A TextReader that contains </param>
		public WktStreamTokenizer(TextReader reader) : base(reader, true)
		{
			if (reader==null)
			{
				throw new ArgumentNullException("reader");
			}
		}
		#endregion

		#region Methods

		/// <summary>
		/// Reads a token and checks it is what is expected.
		/// </summary>
		/// <param name="expectedToken">The expected token.</param>
		internal void ReadToken(string expectedToken)
		{
			this.NextToken();
			if (this.GetStringValue()!=expectedToken)
			{
				throw new Exception(String.Format(SharpMap.Map.numberFormat_EnUS, "Expecting ('{3}') but got a '{0}' at line {1} column {2}.", this.GetStringValue(), this.LineNumber, this.Column, expectedToken));
			}
		}
		
		/// <summary>
		/// Reads a string inside double quotes.
		/// </summary>
		/// <remarks>
		/// White space inside quotes is preserved.
		/// </remarks>
		/// <returns>The string inside the double quotes.</returns>
		public string ReadDoubleQuotedWord()
		{
			string word="";
			ReadToken("\"");	
			NextToken(false);
			while (GetStringValue()!="\"")
			{
				word = word+ this.GetStringValue();
				NextToken(false);
			} 
			return word;
		}

		/// <summary>
		/// Reads the authority and authority code.
		/// </summary>
		/// <param name="authority">String to place the authority in.</param>
		/// <param name="authorityCode">String to place the authority code in.</param>
		public void ReadAuthority(ref string authority,ref long authorityCode)
		{
			//AUTHORITY["EPGS","9102"]]
			if(GetStringValue() != "AUTHORITY")
				ReadToken("AUTHORITY");
			ReadToken("[");
			authority = this.ReadDoubleQuotedWord();
			ReadToken(",");
			long.TryParse(this.ReadDoubleQuotedWord(),out authorityCode);			
			ReadToken("]");
		}
		#endregion

	}
}