class1.cs

《c#技术内幕代码》

using System;

namespace CH14_4
{
	public class SuperString
	{
		private string fString;

		public SuperString()
		{
			fString = "";
		}
		public SuperString( string inStr )
		{
			fString = inStr;
		}
		public string ToStr()
		{
			return fString;
		}
		// Return the rightmost n characters
		public string Right( int nChars )
		{
			if ( nChars > fString.Length )
				return fString;

			string s = "";
			for ( int i=fString.Length-nChars; i<fString.Length; ++i )
				s += fString[i];
			return s;
		}
		public string Left( int nChars )
		{
			if ( nChars > fString.Length )
				return fString;
			string s = "";
			for ( int i=0; i<nChars; ++i )
				s += fString[i];
			return s;
		}
		public string Mid( int nStart, int nEnd )
		{
			if ( nStart < 0 || nEnd > fString.Length )
				return fString;
			if ( nStart > nEnd )
				return "";
			
			string s = "";
			for ( int i=nStart; i<nEnd; ++i )
				s += fString[i];
			return s;
		}
	}

	class Class1
	{
		static void Main(string[] args)
		{
			SuperString s = new SuperString("Hello world");
			System.Console.WriteLine("s = {0}", s.ToStr() );
			System.Console.WriteLine("Right 3 = [{0}]", s.Right(3));
			System.Console.WriteLine("Left 6 = [{0}]", s.Left(6));
			System.Console.WriteLine("Mid 2,4 = [{0}]", s.Mid(2,4));
		}
	}
}