source: trunk/yao/share/antlr-2.7.7/lib/csharp/antlr.runtime/antlr/StringUtils.cs @ 1

using System;

namespace antlr
{
        /* ANTLR Translator Generator
         * Project led by Terence Parr at http://www.jGuru.com
         * Software rights: http://www.antlr.org/license.html
         *
         * $Id:$
         */
        //
        // ANTLR C# Code Generator by Micheal Jordan
        //                            Kunle Odutola       : kunle UNDERSCORE odutola AT hotmail DOT com
        //                            Anthony Oguntimehin
        //
        // With many thanks to Eric V. Smith from the ANTLR list.
        //
        
        public class StringUtils
        {
                /*General-purpose utility function for removing
                * characters from back of string
                * @param s The string to process
                * @param c The character to remove
                * @return The resulting string
                */
                static public string stripBack(string s, char c)
                {
                        while (s.Length > 0 && s[s.Length - 1] == c)
                        {
                                s = s.Substring(0, (s.Length - 1) - (0));
                        }
                        return s;
                }
                
                /*General-purpose utility function for removing
                * characters from back of string
                * @param s The string to process
                * @param remove A string containing the set of characters to remove
                * @return The resulting string
                */
                static public string stripBack(string s, string remove)
                {
                        bool changed;
                        do 
                        {
                                changed = false;
                                 for (int i = 0; i < remove.Length; i++)
                                {
                                        char c = remove[i];
                                        while (s.Length > 0 && s[s.Length - 1] == c)
                                        {
                                                changed = true;
                                                s = s.Substring(0, (s.Length - 1) - (0));
                                        }
                                }
                        }
                        while (changed);
                        return s;
                }
                
                /*General-purpose utility function for removing
                * characters from front of string
                * @param s The string to process
                * @param c The character to remove
                * @return The resulting string
                */
                static public string stripFront(string s, char c)
                {
                        while (s.Length > 0 && s[0] == c)
                        {
                                s = s.Substring(1);
                        }
                        return s;
                }
                
                /*General-purpose utility function for removing
                * characters from front of string
                * @param s The string to process
                * @param remove A string containing the set of characters to remove
                * @return The resulting string
                */
                static public string stripFront(string s, string remove)
                {
                        bool changed;
                        do 
                        {
                                changed = false;
                                 for (int i = 0; i < remove.Length; i++)
                                {
                                        char c = remove[i];
                                        while (s.Length > 0 && s[0] == c)
                                        {
                                                changed = true;
                                                s = s.Substring(1);
                                        }
                                }
                        }
                        while (changed);
                        return s;
                }
                
                /*General-purpose utility function for removing
                * characters from the front and back of string
                * @param s The string to process
                * @param head exact string to strip from head
                * @param tail exact string to strip from tail
                * @return The resulting string
                */
                public static string stripFrontBack(string src, string head, string tail)
                {
                        int h = src.IndexOf(head);
                        int t = src.LastIndexOf(tail);
                        if (h == - 1 || t == - 1)
                                return src;
                        return src.Substring(h + 1, (t) - (h + 1));
                }
        }
}