//******************************************************************************************************//  CharExtensions.cs - Gbtc////  Copyright © 2012, Grid Protection Alliance.  All Rights Reserved.////  Licensed to the Grid Protection Alliance (GPA) under one or more contributor license agreements. See//  the NOTICE file distributed with this work for additional information regarding copyright ownership.//  The GPA licenses this file to you under the MIT License (MIT), the "License"; you may//  not use this file except in compliance with the License. You may obtain a copy of the License at:////      http://www.opensource.org/licenses/MIT////  Unless agreed to in writing, the subject software distributed under the License is distributed on an//  "AS-IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. Refer to the//  License for the specific language governing permissions and limitations.////  Code Modification History://  ----------------------------------------------------------------------------------------------------//  12/13/2008 - F. Russell Robertson//       Generated original version of source code.//  08/3/2009 - Josh L. Patterson//       Updated comments.//  09/14/2009 - Stephen C. Wills//       Added new header and license agreement.//  01/04/2010 - Andrew K. Hill//       Modified the following methods per unit testing://       IsAny(char, IEnumerable<char>)//  12/02/2010 - J. Ritchie Carroll//       Modified IsWordTerminator to use standard Unicode character tests.//  12/14/2012 - Starlynn Danyelle Gilliam//       Modified Header.////****************************************************************************************************** using System;using System.Collections;using System.Collections.Generic;using System.Globalization; namespace GSF{    /// <summary>    /// Defines extension functions related to character manipulation.    /// </summary>    public static class CharExtensions    {        // so that this only happens one time        private static readonly char[] wordSeperators = { '\"', '/', '\\', '<', '>', '=', '{', '}', '(', ')', '[', ']', '@', '*' };        private static readonly char[] numericValues = { '-', '+', ',', '.' };         /// <summary>        /// Encodes the specified Unicode character in proper Regular Expression format.        /// </summary>        /// <param name="item">Unicode character to encode in Regular Expression format.</param>        /// <returns>Specified Unicode character in proper Regular Expression format.</returns>        public static string RegexEncode(this char item)        {            return "\\u" + Convert.ToUInt16(item).ToString("x").PadLeft(4, '0');        }         /// <summary>        /// Tests a character to determine if it marks the end of a typical English word.        /// </summary>        /// <param name="value">Input character to check.</param>        /// <returns><c>true</c> if character is a work separator.</returns>        /// <remarks>        /// Performs no testing for ASCII codes &gt; 127.<br/>        /// Does not separate words based on punctuation of ' %  - _  <br/>        /// However does include the angle bracket symbols &lt; &gt; as separators<br/>        /// <br/>        /// For reference the standard char tests are:        /// <ul>        /// <li>"IsSperator (1) == simple space (32 or 160) only.</li>        /// <li>IsPunctuation (23) == . , ! ? : ; " ' [ ] { } ( ) \ / @ % # * &amp; - _  (plus other char's &gt; 127)</li>        /// <li>IsSymbol (8) == $ + &lt; &gt; = ^ ` ~</li>        /// <li>IsWhiteSpace (6) == control char's 9 thru 13, plus 32 -- TAB, LF, VT, FF, CR, SP</li>        /// </ul>        /// </remarks>        public static bool IsWordTerminator(this char value)        {            if (char.IsPunctuation(value) || char.IsWhiteSpace(value) || char.IsSymbol(value) || char.IsControl(value))                return true;             return value.IsAnyOf(wordSeperators);        }         /// <summary>        /// Tests a character to determine if is a common part of a numeric string (digits or one of "+ - , .")        /// </summary>        /// <param name="value">The character to check.</param>        /// <returns><c>true</c> if numeric character.</returns>        public static bool IsNumeric(this char value)        {            if (char.IsDigit(value))                return true;             return value.IsAnyOf(numericValues);        }         /// <summary>        /// Determines if a character matches any character in a sent array.        /// </summary>        /// <param name="value">The character to check.</param>        /// <param name="testChars">The array of characters to test.</param>        /// <returns>Boolean value indicating a that the character is in the array.</returns>        public static bool IsAnyOf(this char value, IEnumerable<char> testChars)        {            if ((object)testChars == null)                throw new ArgumentNullException(nameof(testChars));             foreach (char c in testChars)            {                if (value == c)                    return true;            }             return false;        }         /// <summary>        /// Tests a character to determine if it is between a specified character range        /// </summary>        /// <param name="value">Input character to process.</param>        /// <param name="startOfRange">Beginning of range character.</param>        /// <param name="endOfRange">End of range character.</param>        /// <returns><c>true</c> is the character is within the range.</returns>        public static bool IsInRange(this char value, char startOfRange, char endOfRange)        {            if (value >= startOfRange && value <= endOfRange)                return true;             return false;        }         //**********  New methods July 2017, To Be Tested   ********************         /// <summary>        /// Converts <paramref name="value"/> to lower case        /// </summary>        /// <returns>        /// <paramref name="value"/> converted to lower case        /// </returns>        public static char ToLower(this char value) => char.ToLowerInvariant(value);         /// <summary>        /// Converts <paramref name="value"/> to upper case        /// </summary>        /// <returns>        /// <paramref name="value"/> converted to upper case        /// </returns>        public static char ToUpper(this char value) => char.ToUpperInvariant(value);         /// <summary>        /// Returns true if char is hexadecimal digit.        /// </summary>        /// <param name="value">The character to be tested.</param>        /// <returns>true if char is hexadecimal digit; false otherwise</returns>        public static bool IsHex(this char value)        {            return                (value >= '0' && value <= '9') ||                (value >= 'A' && value <= 'F') ||                (value >= 'a' && value <= 'f');        }         /// <summary>        /// Converts a hexadecimal character to the integer equivalent.        /// </summary>        /// <param name="value">A valid hexadecimal character.</param>        /// <returns>The integer equivalent of the given hexadecimal character.</returns>        public static int ConvertHexToInt(this char value)        {            if (!IsHex(value))                throw new ArgumentException("Character must be a hexadecimal character.");             if (value < 58)                return (int)(value - 48);             value = char.ToUpper(value);            return (int)(value - 55);        }         /// <summary>        /// Converts a hexadecimal character to a 4-bit integer equivalent.        /// </summary>        /// <param name="value">A valid hexadecimal character.</param>        /// <returns>A 4-bit <see cref="BitArray"/> representing the integer equivalent of the given hexadecimal character.</returns>        public static BitArray ConvertHexToBitArray(this char value)        {            if (!IsHex(value))                throw new ArgumentException("Character must be a hexadecimal character.");             BitArray ba = new BitArray(4);            byte b = byte.Parse(value.ToString(), NumberStyles.HexNumber);             for (int j = 0; j < 4; j++)                ba.Set(j, (b & (1 << (3 - j))) != 0);             return ba;        }    }}