--- /dev/null
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+/*============================================================
+**
+**
+**
+** Purpose: This is the value class representing a Unicode character
+** Char methods until we create this functionality.
+**
+**
+===========================================================*/
+
+using System.Diagnostics;
+using System.Diagnostics.Contracts;
+using System.Globalization;
+using System.Runtime.InteropServices;
+
+namespace System
+{
+ [Serializable]
+ [StructLayout(LayoutKind.Sequential)]
+ public struct Char : IComparable, IComparable<Char>, IEquatable<Char>, IConvertible
+ {
+ //
+ // Member Variables
+ //
+ internal char m_value;
+
+ //
+ // Public Constants
+ //
+ // The maximum character value.
+ public const char MaxValue = (char)0xFFFF;
+ // The minimum character value.
+ public const char MinValue = (char)0x00;
+
+ // Unicode category values from Unicode U+0000 ~ U+00FF. Store them in byte[] array to save space.
+ private static readonly byte[] s_categoryForLatin1 = {
+ (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, // 0000 - 0007
+ (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, // 0008 - 000F
+ (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, // 0010 - 0017
+ (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, // 0018 - 001F
+ (byte)UnicodeCategory.SpaceSeparator, (byte)UnicodeCategory.OtherPunctuation, (byte)UnicodeCategory.OtherPunctuation, (byte)UnicodeCategory.OtherPunctuation, (byte)UnicodeCategory.CurrencySymbol, (byte)UnicodeCategory.OtherPunctuation, (byte)UnicodeCategory.OtherPunctuation, (byte)UnicodeCategory.OtherPunctuation, // 0020 - 0027
+ (byte)UnicodeCategory.OpenPunctuation, (byte)UnicodeCategory.ClosePunctuation, (byte)UnicodeCategory.OtherPunctuation, (byte)UnicodeCategory.MathSymbol, (byte)UnicodeCategory.OtherPunctuation, (byte)UnicodeCategory.DashPunctuation, (byte)UnicodeCategory.OtherPunctuation, (byte)UnicodeCategory.OtherPunctuation, // 0028 - 002F
+ (byte)UnicodeCategory.DecimalDigitNumber, (byte)UnicodeCategory.DecimalDigitNumber, (byte)UnicodeCategory.DecimalDigitNumber, (byte)UnicodeCategory.DecimalDigitNumber, (byte)UnicodeCategory.DecimalDigitNumber, (byte)UnicodeCategory.DecimalDigitNumber, (byte)UnicodeCategory.DecimalDigitNumber, (byte)UnicodeCategory.DecimalDigitNumber, // 0030 - 0037
+ (byte)UnicodeCategory.DecimalDigitNumber, (byte)UnicodeCategory.DecimalDigitNumber, (byte)UnicodeCategory.OtherPunctuation, (byte)UnicodeCategory.OtherPunctuation, (byte)UnicodeCategory.MathSymbol, (byte)UnicodeCategory.MathSymbol, (byte)UnicodeCategory.MathSymbol, (byte)UnicodeCategory.OtherPunctuation, // 0038 - 003F
+ (byte)UnicodeCategory.OtherPunctuation, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, // 0040 - 0047
+ (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, // 0048 - 004F
+ (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, // 0050 - 0057
+ (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.OpenPunctuation, (byte)UnicodeCategory.OtherPunctuation, (byte)UnicodeCategory.ClosePunctuation, (byte)UnicodeCategory.ModifierSymbol, (byte)UnicodeCategory.ConnectorPunctuation, // 0058 - 005F
+ (byte)UnicodeCategory.ModifierSymbol, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, // 0060 - 0067
+ (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, // 0068 - 006F
+ (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, // 0070 - 0077
+ (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.OpenPunctuation, (byte)UnicodeCategory.MathSymbol, (byte)UnicodeCategory.ClosePunctuation, (byte)UnicodeCategory.MathSymbol, (byte)UnicodeCategory.Control, // 0078 - 007F
+ (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, // 0080 - 0087
+ (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, // 0088 - 008F
+ (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, // 0090 - 0097
+ (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, (byte)UnicodeCategory.Control, // 0098 - 009F
+ (byte)UnicodeCategory.SpaceSeparator, (byte)UnicodeCategory.OtherPunctuation, (byte)UnicodeCategory.CurrencySymbol, (byte)UnicodeCategory.CurrencySymbol, (byte)UnicodeCategory.CurrencySymbol, (byte)UnicodeCategory.CurrencySymbol, (byte)UnicodeCategory.OtherSymbol, (byte)UnicodeCategory.OtherSymbol, // 00A0 - 00A7
+ (byte)UnicodeCategory.ModifierSymbol, (byte)UnicodeCategory.OtherSymbol, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.InitialQuotePunctuation, (byte)UnicodeCategory.MathSymbol, (byte)UnicodeCategory.DashPunctuation, (byte)UnicodeCategory.OtherSymbol, (byte)UnicodeCategory.ModifierSymbol, // 00A8 - 00AF
+ (byte)UnicodeCategory.OtherSymbol, (byte)UnicodeCategory.MathSymbol, (byte)UnicodeCategory.OtherNumber, (byte)UnicodeCategory.OtherNumber, (byte)UnicodeCategory.ModifierSymbol, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.OtherSymbol, (byte)UnicodeCategory.OtherPunctuation, // 00B0 - 00B7
+ (byte)UnicodeCategory.ModifierSymbol, (byte)UnicodeCategory.OtherNumber, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.FinalQuotePunctuation, (byte)UnicodeCategory.OtherNumber, (byte)UnicodeCategory.OtherNumber, (byte)UnicodeCategory.OtherNumber, (byte)UnicodeCategory.OtherPunctuation, // 00B8 - 00BF
+ (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, // 00C0 - 00C7
+ (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, // 00C8 - 00CF
+ (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.MathSymbol, // 00D0 - 00D7
+ (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.UppercaseLetter, (byte)UnicodeCategory.LowercaseLetter, // 00D8 - 00DF
+ (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, // 00E0 - 00E7
+ (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, // 00E8 - 00EF
+ (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.MathSymbol, // 00F0 - 00F7
+ (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, (byte)UnicodeCategory.LowercaseLetter, // 00F8 - 00FF
+ };
+
+ // Return true for all characters below or equal U+00ff, which is ASCII + Latin-1 Supplement.
+ private static bool IsLatin1(char ch)
+ {
+ return (ch <= '\x00ff');
+ }
+
+ // Return true for all characters below or equal U+007f, which is ASCII.
+ private static bool IsAscii(char ch)
+ {
+ return (ch <= '\x007f');
+ }
+
+ // Return the Unicode category for Unicode character <= 0x00ff.
+ private static UnicodeCategory GetLatin1UnicodeCategory(char ch)
+ {
+ Debug.Assert(IsLatin1(ch), "Char.GetLatin1UnicodeCategory(): ch should be <= 007f");
+ return (UnicodeCategory)(s_categoryForLatin1[(int)ch]);
+ }
+
+ //
+ // Private Constants
+ //
+
+ //
+ // Overriden Instance Methods
+ //
+
+ // Calculate a hashcode for a 2 byte Unicode character.
+ public override int GetHashCode()
+ {
+ return (int)m_value | ((int)m_value << 16);
+ }
+
+ // Used for comparing two boxed Char objects.
+ //
+ public override bool Equals(Object obj)
+ {
+ if (!(obj is Char))
+ {
+ return false;
+ }
+ return (m_value == ((Char)obj).m_value);
+ }
+
+ [System.Runtime.Versioning.NonVersionable]
+ public bool Equals(Char obj)
+ {
+ return m_value == obj;
+ }
+
+ // Compares this object to another object, returning an integer that
+ // indicates the relationship.
+ // Returns a value less than zero if this object
+ // null is considered to be less than any instance.
+ // If object is not of type Char, this method throws an ArgumentException.
+ //
+ [Pure]
+ public int CompareTo(Object value)
+ {
+ if (value == null)
+ {
+ return 1;
+ }
+ if (!(value is Char))
+ {
+ throw new ArgumentException(SR.Arg_MustBeChar);
+ }
+
+ return (m_value - ((Char)value).m_value);
+ }
+
+ [Pure]
+ public int CompareTo(Char value)
+ {
+ return (m_value - value);
+ }
+
+ // Overrides System.Object.ToString.
+ [Pure]
+ public override String ToString()
+ {
+ Contract.Ensures(Contract.Result<String>() != null);
+ return Char.ToString(m_value);
+ }
+
+ [Pure]
+ public String ToString(IFormatProvider provider)
+ {
+ Contract.Ensures(Contract.Result<String>() != null);
+ return Char.ToString(m_value);
+ }
+
+ //
+ // Formatting Methods
+ //
+
+ /*===================================ToString===================================
+ **This static methods takes a character and returns the String representation of it.
+ ==============================================================================*/
+ // Provides a string representation of a character.
+ [Pure]
+ public static string ToString(char c) => string.CreateFromChar(c);
+
+ public static char Parse(String s)
+ {
+ if (s == null)
+ {
+ throw new ArgumentNullException(nameof(s));
+ }
+ Contract.EndContractBlock();
+
+ if (s.Length != 1)
+ {
+ throw new FormatException(SR.Format_NeedSingleChar);
+ }
+ return s[0];
+ }
+
+ public static bool TryParse(String s, out Char result)
+ {
+ result = '\0';
+ if (s == null)
+ {
+ return false;
+ }
+ if (s.Length != 1)
+ {
+ return false;
+ }
+ result = s[0];
+ return true;
+ }
+
+ //
+ // Static Methods
+ //
+ /*=================================ISDIGIT======================================
+ **A wrapper for Char. Returns a boolean indicating whether **
+ **character c is considered to be a digit. **
+ ==============================================================================*/
+ // Determines whether a character is a digit.
+ [Pure]
+ public static bool IsDigit(char c)
+ {
+ if (IsLatin1(c))
+ {
+ return (c >= '0' && c <= '9');
+ }
+ return (CharUnicodeInfo.GetUnicodeCategory(c) == UnicodeCategory.DecimalDigitNumber);
+ }
+
+
+ /*=================================CheckLetter=====================================
+ ** Check if the specified UnicodeCategory belongs to the letter categories.
+ ==============================================================================*/
+ internal static bool CheckLetter(UnicodeCategory uc)
+ {
+ switch (uc)
+ {
+ case (UnicodeCategory.UppercaseLetter):
+ case (UnicodeCategory.LowercaseLetter):
+ case (UnicodeCategory.TitlecaseLetter):
+ case (UnicodeCategory.ModifierLetter):
+ case (UnicodeCategory.OtherLetter):
+ return (true);
+ }
+ return (false);
+ }
+
+ /*=================================ISLETTER=====================================
+ **A wrapper for Char. Returns a boolean indicating whether **
+ **character c is considered to be a letter. **
+ ==============================================================================*/
+ // Determines whether a character is a letter.
+ [Pure]
+ public static bool IsLetter(char c)
+ {
+ if (IsLatin1(c))
+ {
+ if (IsAscii(c))
+ {
+ c |= (char)0x20;
+ return ((c >= 'a' && c <= 'z'));
+ }
+ return (CheckLetter(GetLatin1UnicodeCategory(c)));
+ }
+ return (CheckLetter(CharUnicodeInfo.GetUnicodeCategory(c)));
+ }
+
+ private static bool IsWhiteSpaceLatin1(char c)
+ {
+ // There are characters which belong to UnicodeCategory.Control but are considered as white spaces.
+ // We use code point comparisons for these characters here as a temporary fix.
+
+ // U+0009 = <control> HORIZONTAL TAB
+ // U+000a = <control> LINE FEED
+ // U+000b = <control> VERTICAL TAB
+ // U+000c = <contorl> FORM FEED
+ // U+000d = <control> CARRIAGE RETURN
+ // U+0085 = <control> NEXT LINE
+ // U+00a0 = NO-BREAK SPACE
+ if ((c == ' ') || (c >= '\x0009' && c <= '\x000d') || c == '\x00a0' || c == '\x0085')
+ {
+ return (true);
+ }
+ return (false);
+ }
+
+ /*===============================ISWHITESPACE===================================
+ **A wrapper for Char. Returns a boolean indicating whether **
+ **character c is considered to be a whitespace character. **
+ ==============================================================================*/
+ // Determines whether a character is whitespace.
+ [Pure]
+ public static bool IsWhiteSpace(char c)
+ {
+ if (IsLatin1(c))
+ {
+ return (IsWhiteSpaceLatin1(c));
+ }
+ return CharUnicodeInfo.IsWhiteSpace(c);
+ }
+
+
+ /*===================================IsUpper====================================
+ **Arguments: c -- the characater to be checked.
+ **Returns: True if c is an uppercase character.
+ ==============================================================================*/
+ // Determines whether a character is upper-case.
+ [Pure]
+ public static bool IsUpper(char c)
+ {
+ if (IsLatin1(c))
+ {
+ if (IsAscii(c))
+ {
+ return (c >= 'A' && c <= 'Z');
+ }
+ return (GetLatin1UnicodeCategory(c) == UnicodeCategory.UppercaseLetter);
+ }
+ return (CharUnicodeInfo.GetUnicodeCategory(c) == UnicodeCategory.UppercaseLetter);
+ }
+
+ /*===================================IsLower====================================
+ **Arguments: c -- the characater to be checked.
+ **Returns: True if c is an lowercase character.
+ ==============================================================================*/
+ // Determines whether a character is lower-case.
+ [Pure]
+ public static bool IsLower(char c)
+ {
+ if (IsLatin1(c))
+ {
+ if (IsAscii(c))
+ {
+ return (c >= 'a' && c <= 'z');
+ }
+ return (GetLatin1UnicodeCategory(c) == UnicodeCategory.LowercaseLetter);
+ }
+ return (CharUnicodeInfo.GetUnicodeCategory(c) == UnicodeCategory.LowercaseLetter);
+ }
+
+ internal static bool CheckPunctuation(UnicodeCategory uc)
+ {
+ switch (uc)
+ {
+ case UnicodeCategory.ConnectorPunctuation:
+ case UnicodeCategory.DashPunctuation:
+ case UnicodeCategory.OpenPunctuation:
+ case UnicodeCategory.ClosePunctuation:
+ case UnicodeCategory.InitialQuotePunctuation:
+ case UnicodeCategory.FinalQuotePunctuation:
+ case UnicodeCategory.OtherPunctuation:
+ return (true);
+ }
+ return (false);
+ }
+
+
+ /*================================IsPunctuation=================================
+ **Arguments: c -- the characater to be checked.
+ **Returns: True if c is an punctuation mark
+ ==============================================================================*/
+ // Determines whether a character is a punctuation mark.
+ [Pure]
+ public static bool IsPunctuation(char c)
+ {
+ if (IsLatin1(c))
+ {
+ return (CheckPunctuation(GetLatin1UnicodeCategory(c)));
+ }
+ return (CheckPunctuation(CharUnicodeInfo.GetUnicodeCategory(c)));
+ }
+
+ /*=================================CheckLetterOrDigit=====================================
+ ** Check if the specified UnicodeCategory belongs to the letter or digit categories.
+ ==============================================================================*/
+ internal static bool CheckLetterOrDigit(UnicodeCategory uc)
+ {
+ switch (uc)
+ {
+ case UnicodeCategory.UppercaseLetter:
+ case UnicodeCategory.LowercaseLetter:
+ case UnicodeCategory.TitlecaseLetter:
+ case UnicodeCategory.ModifierLetter:
+ case UnicodeCategory.OtherLetter:
+ case UnicodeCategory.DecimalDigitNumber:
+ return (true);
+ }
+ return (false);
+ }
+
+ // Determines whether a character is a letter or a digit.
+ [Pure]
+ public static bool IsLetterOrDigit(char c)
+ {
+ if (IsLatin1(c))
+ {
+ return (CheckLetterOrDigit(GetLatin1UnicodeCategory(c)));
+ }
+ return (CheckLetterOrDigit(CharUnicodeInfo.GetUnicodeCategory(c)));
+ }
+
+ /*===================================ToUpper====================================
+ **
+ ==============================================================================*/
+ // Converts a character to upper-case for the specified culture.
+ // <;<;Not fully implemented>;>;
+ public static char ToUpper(char c, CultureInfo culture)
+ {
+ if (culture == null)
+ throw new ArgumentNullException(nameof(culture));
+ Contract.EndContractBlock();
+ return culture.TextInfo.ToUpper(c);
+ }
+
+ /*=================================TOUPPER======================================
+ **A wrapper for Char.toUpperCase. Converts character c to its **
+ **uppercase equivalent. If c is already an uppercase character or is not an **
+ **alphabetic, nothing happens. **
+ ==============================================================================*/
+ // Converts a character to upper-case for the default culture.
+ //
+ public static char ToUpper(char c)
+ {
+ return ToUpper(c, CultureInfo.CurrentCulture);
+ }
+
+
+ // Converts a character to upper-case for invariant culture.
+ public static char ToUpperInvariant(char c)
+ {
+ return ToUpper(c, CultureInfo.InvariantCulture);
+ }
+
+
+ /*===================================ToLower====================================
+ **
+ ==============================================================================*/
+ // Converts a character to lower-case for the specified culture.
+ // <;<;Not fully implemented>;>;
+ public static char ToLower(char c, CultureInfo culture)
+ {
+ if (culture == null)
+ throw new ArgumentNullException(nameof(culture));
+ Contract.EndContractBlock();
+ return culture.TextInfo.ToLower(c);
+ }
+
+ /*=================================TOLOWER======================================
+ **A wrapper for Char.toLowerCase. Converts character c to its **
+ **lowercase equivalent. If c is already a lowercase character or is not an **
+ **alphabetic, nothing happens. **
+ ==============================================================================*/
+ // Converts a character to lower-case for the default culture.
+ public static char ToLower(char c)
+ {
+ return ToLower(c, CultureInfo.CurrentCulture);
+ }
+
+
+ // Converts a character to lower-case for invariant culture.
+ public static char ToLowerInvariant(char c)
+ {
+ return ToLower(c, CultureInfo.InvariantCulture);
+ }
+
+
+ //
+ // IConvertible implementation
+ //
+ [Pure]
+ public TypeCode GetTypeCode()
+ {
+ return TypeCode.Char;
+ }
+
+
+ bool IConvertible.ToBoolean(IFormatProvider provider)
+ {
+ throw new InvalidCastException(SR.Format(SR.InvalidCast_FromTo, "Char", "Boolean"));
+ }
+
+ char IConvertible.ToChar(IFormatProvider provider)
+ {
+ return m_value;
+ }
+
+ sbyte IConvertible.ToSByte(IFormatProvider provider)
+ {
+ return Convert.ToSByte(m_value);
+ }
+
+ byte IConvertible.ToByte(IFormatProvider provider)
+ {
+ return Convert.ToByte(m_value);
+ }
+
+ short IConvertible.ToInt16(IFormatProvider provider)
+ {
+ return Convert.ToInt16(m_value);
+ }
+
+ ushort IConvertible.ToUInt16(IFormatProvider provider)
+ {
+ return Convert.ToUInt16(m_value);
+ }
+
+ int IConvertible.ToInt32(IFormatProvider provider)
+ {
+ return Convert.ToInt32(m_value);
+ }
+
+ uint IConvertible.ToUInt32(IFormatProvider provider)
+ {
+ return Convert.ToUInt32(m_value);
+ }
+
+ long IConvertible.ToInt64(IFormatProvider provider)
+ {
+ return Convert.ToInt64(m_value);
+ }
+
+ ulong IConvertible.ToUInt64(IFormatProvider provider)
+ {
+ return Convert.ToUInt64(m_value);
+ }
+
+ float IConvertible.ToSingle(IFormatProvider provider)
+ {
+ throw new InvalidCastException(SR.Format(SR.InvalidCast_FromTo, "Char", "Single"));
+ }
+
+ double IConvertible.ToDouble(IFormatProvider provider)
+ {
+ throw new InvalidCastException(SR.Format(SR.InvalidCast_FromTo, "Char", "Double"));
+ }
+
+ Decimal IConvertible.ToDecimal(IFormatProvider provider)
+ {
+ throw new InvalidCastException(SR.Format(SR.InvalidCast_FromTo, "Char", "Decimal"));
+ }
+
+ DateTime IConvertible.ToDateTime(IFormatProvider provider)
+ {
+ throw new InvalidCastException(SR.Format(SR.InvalidCast_FromTo, "Char", "DateTime"));
+ }
+
+ Object IConvertible.ToType(Type type, IFormatProvider provider)
+ {
+ return Convert.DefaultToType((IConvertible)this, type, provider);
+ }
+ public static bool IsControl(char c)
+ {
+ if (IsLatin1(c))
+ {
+ return (GetLatin1UnicodeCategory(c) == UnicodeCategory.Control);
+ }
+ return (CharUnicodeInfo.GetUnicodeCategory(c) == UnicodeCategory.Control);
+ }
+
+ public static bool IsControl(String s, int index)
+ {
+ if (s == null)
+ throw new ArgumentNullException(nameof(s));
+ if (((uint)index) >= ((uint)s.Length))
+ {
+ throw new ArgumentOutOfRangeException(nameof(index));
+ }
+ Contract.EndContractBlock();
+ char c = s[index];
+ if (IsLatin1(c))
+ {
+ return (GetLatin1UnicodeCategory(c) == UnicodeCategory.Control);
+ }
+ return (CharUnicodeInfo.GetUnicodeCategory(s, index) == UnicodeCategory.Control);
+ }
+
+
+ public static bool IsDigit(String s, int index)
+ {
+ if (s == null)
+ throw new ArgumentNullException(nameof(s));
+ if (((uint)index) >= ((uint)s.Length))
+ {
+ throw new ArgumentOutOfRangeException(nameof(index));
+ }
+ Contract.EndContractBlock();
+ char c = s[index];
+ if (IsLatin1(c))
+ {
+ return (c >= '0' && c <= '9');
+ }
+ return (CharUnicodeInfo.GetUnicodeCategory(s, index) == UnicodeCategory.DecimalDigitNumber);
+ }
+
+ public static bool IsLetter(String s, int index)
+ {
+ if (s == null)
+ throw new ArgumentNullException(nameof(s));
+ if (((uint)index) >= ((uint)s.Length))
+ {
+ throw new ArgumentOutOfRangeException(nameof(index));
+ }
+ Contract.EndContractBlock();
+ char c = s[index];
+ if (IsLatin1(c))
+ {
+ if (IsAscii(c))
+ {
+ c |= (char)0x20;
+ return ((c >= 'a' && c <= 'z'));
+ }
+ return (CheckLetter(GetLatin1UnicodeCategory(c)));
+ }
+ return (CheckLetter(CharUnicodeInfo.GetUnicodeCategory(s, index)));
+ }
+
+ public static bool IsLetterOrDigit(String s, int index)
+ {
+ if (s == null)
+ throw new ArgumentNullException(nameof(s));
+ if (((uint)index) >= ((uint)s.Length))
+ {
+ throw new ArgumentOutOfRangeException(nameof(index));
+ }
+ Contract.EndContractBlock();
+ char c = s[index];
+ if (IsLatin1(c))
+ {
+ return CheckLetterOrDigit(GetLatin1UnicodeCategory(c));
+ }
+ return CheckLetterOrDigit(CharUnicodeInfo.GetUnicodeCategory(s, index));
+ }
+
+ public static bool IsLower(String s, int index)
+ {
+ if (s == null)
+ throw new ArgumentNullException(nameof(s));
+ if (((uint)index) >= ((uint)s.Length))
+ {
+ throw new ArgumentOutOfRangeException(nameof(index));
+ }
+ Contract.EndContractBlock();
+ char c = s[index];
+ if (IsLatin1(c))
+ {
+ if (IsAscii(c))
+ {
+ return (c >= 'a' && c <= 'z');
+ }
+ return (GetLatin1UnicodeCategory(c) == UnicodeCategory.LowercaseLetter);
+ }
+
+ return (CharUnicodeInfo.GetUnicodeCategory(s, index) == UnicodeCategory.LowercaseLetter);
+ }
+
+ /*=================================CheckNumber=====================================
+ ** Check if the specified UnicodeCategory belongs to the number categories.
+ ==============================================================================*/
+
+ internal static bool CheckNumber(UnicodeCategory uc)
+ {
+ switch (uc)
+ {
+ case (UnicodeCategory.DecimalDigitNumber):
+ case (UnicodeCategory.LetterNumber):
+ case (UnicodeCategory.OtherNumber):
+ return (true);
+ }
+ return (false);
+ }
+
+ public static bool IsNumber(char c)
+ {
+ if (IsLatin1(c))
+ {
+ if (IsAscii(c))
+ {
+ return (c >= '0' && c <= '9');
+ }
+ return (CheckNumber(GetLatin1UnicodeCategory(c)));
+ }
+ return (CheckNumber(CharUnicodeInfo.GetUnicodeCategory(c)));
+ }
+
+ public static bool IsNumber(String s, int index)
+ {
+ if (s == null)
+ throw new ArgumentNullException(nameof(s));
+ if (((uint)index) >= ((uint)s.Length))
+ {
+ throw new ArgumentOutOfRangeException(nameof(index));
+ }
+ Contract.EndContractBlock();
+ char c = s[index];
+ if (IsLatin1(c))
+ {
+ if (IsAscii(c))
+ {
+ return (c >= '0' && c <= '9');
+ }
+ return (CheckNumber(GetLatin1UnicodeCategory(c)));
+ }
+ return (CheckNumber(CharUnicodeInfo.GetUnicodeCategory(s, index)));
+ }
+
+ ////////////////////////////////////////////////////////////////////////
+ //
+ // IsPunctuation
+ //
+ // Determines if the given character is a punctuation character.
+ //
+ ////////////////////////////////////////////////////////////////////////
+
+ public static bool IsPunctuation(String s, int index)
+ {
+ if (s == null)
+ throw new ArgumentNullException(nameof(s));
+ if (((uint)index) >= ((uint)s.Length))
+ {
+ throw new ArgumentOutOfRangeException(nameof(index));
+ }
+ Contract.EndContractBlock();
+ char c = s[index];
+ if (IsLatin1(c))
+ {
+ return (CheckPunctuation(GetLatin1UnicodeCategory(c)));
+ }
+ return (CheckPunctuation(CharUnicodeInfo.GetUnicodeCategory(s, index)));
+ }
+
+
+ /*================================= CheckSeparator ============================
+ ** Check if the specified UnicodeCategory belongs to the seprator categories.
+ ==============================================================================*/
+
+ internal static bool CheckSeparator(UnicodeCategory uc)
+ {
+ switch (uc)
+ {
+ case UnicodeCategory.SpaceSeparator:
+ case UnicodeCategory.LineSeparator:
+ case UnicodeCategory.ParagraphSeparator:
+ return (true);
+ }
+ return (false);
+ }
+
+ private static bool IsSeparatorLatin1(char c)
+ {
+ // U+00a0 = NO-BREAK SPACE
+ // There is no LineSeparator or ParagraphSeparator in Latin 1 range.
+ return (c == '\x0020' || c == '\x00a0');
+ }
+
+ public static bool IsSeparator(char c)
+ {
+ if (IsLatin1(c))
+ {
+ return (IsSeparatorLatin1(c));
+ }
+ return (CheckSeparator(CharUnicodeInfo.GetUnicodeCategory(c)));
+ }
+
+ public static bool IsSeparator(String s, int index)
+ {
+ if (s == null)
+ throw new ArgumentNullException(nameof(s));
+ if (((uint)index) >= ((uint)s.Length))
+ {
+ throw new ArgumentOutOfRangeException(nameof(index));
+ }
+ Contract.EndContractBlock();
+ char c = s[index];
+ if (IsLatin1(c))
+ {
+ return (IsSeparatorLatin1(c));
+ }
+ return (CheckSeparator(CharUnicodeInfo.GetUnicodeCategory(s, index)));
+ }
+
+ [Pure]
+ public static bool IsSurrogate(char c)
+ {
+ return (c >= HIGH_SURROGATE_START && c <= LOW_SURROGATE_END);
+ }
+
+ [Pure]
+ public static bool IsSurrogate(String s, int index)
+ {
+ if (s == null)
+ {
+ throw new ArgumentNullException(nameof(s));
+ }
+ if (((uint)index) >= ((uint)s.Length))
+ {
+ throw new ArgumentOutOfRangeException(nameof(index));
+ }
+ Contract.EndContractBlock();
+ return (IsSurrogate(s[index]));
+ }
+
+ /*================================= CheckSymbol ============================
+ ** Check if the specified UnicodeCategory belongs to the symbol categories.
+ ==============================================================================*/
+
+ internal static bool CheckSymbol(UnicodeCategory uc)
+ {
+ switch (uc)
+ {
+ case (UnicodeCategory.MathSymbol):
+ case (UnicodeCategory.CurrencySymbol):
+ case (UnicodeCategory.ModifierSymbol):
+ case (UnicodeCategory.OtherSymbol):
+ return (true);
+ }
+ return (false);
+ }
+
+ public static bool IsSymbol(char c)
+ {
+ if (IsLatin1(c))
+ {
+ return (CheckSymbol(GetLatin1UnicodeCategory(c)));
+ }
+ return (CheckSymbol(CharUnicodeInfo.GetUnicodeCategory(c)));
+ }
+
+ public static bool IsSymbol(String s, int index)
+ {
+ if (s == null)
+ throw new ArgumentNullException(nameof(s));
+ if (((uint)index) >= ((uint)s.Length))
+ {
+ throw new ArgumentOutOfRangeException(nameof(index));
+ }
+ Contract.EndContractBlock();
+ char c = s[index];
+ if (IsLatin1(c))
+ {
+ return (CheckSymbol(GetLatin1UnicodeCategory(c)));
+ }
+ return (CheckSymbol(CharUnicodeInfo.GetUnicodeCategory(s, index)));
+ }
+
+
+ public static bool IsUpper(String s, int index)
+ {
+ if (s == null)
+ throw new ArgumentNullException(nameof(s));
+ if (((uint)index) >= ((uint)s.Length))
+ {
+ throw new ArgumentOutOfRangeException(nameof(index));
+ }
+ Contract.EndContractBlock();
+ char c = s[index];
+ if (IsLatin1(c))
+ {
+ if (IsAscii(c))
+ {
+ return (c >= 'A' && c <= 'Z');
+ }
+ return (GetLatin1UnicodeCategory(c) == UnicodeCategory.UppercaseLetter);
+ }
+
+ return (CharUnicodeInfo.GetUnicodeCategory(s, index) == UnicodeCategory.UppercaseLetter);
+ }
+
+ public static bool IsWhiteSpace(String s, int index)
+ {
+ if (s == null)
+ throw new ArgumentNullException(nameof(s));
+ if (((uint)index) >= ((uint)s.Length))
+ {
+ throw new ArgumentOutOfRangeException(nameof(index));
+ }
+ Contract.EndContractBlock();
+
+ if (IsLatin1(s[index]))
+ {
+ return IsWhiteSpaceLatin1(s[index]);
+ }
+
+ return CharUnicodeInfo.IsWhiteSpace(s, index);
+ }
+
+ public static UnicodeCategory GetUnicodeCategory(char c)
+ {
+ if (IsLatin1(c))
+ {
+ return (GetLatin1UnicodeCategory(c));
+ }
+ return CharUnicodeInfo.InternalGetUnicodeCategory(c);
+ }
+
+ public static UnicodeCategory GetUnicodeCategory(String s, int index)
+ {
+ if (s == null)
+ throw new ArgumentNullException(nameof(s));
+ if (((uint)index) >= ((uint)s.Length))
+ {
+ throw new ArgumentOutOfRangeException(nameof(index));
+ }
+ Contract.EndContractBlock();
+ if (IsLatin1(s[index]))
+ {
+ return (GetLatin1UnicodeCategory(s[index]));
+ }
+ return CharUnicodeInfo.InternalGetUnicodeCategory(s, index);
+ }
+
+ public static double GetNumericValue(char c)
+ {
+ return CharUnicodeInfo.GetNumericValue(c);
+ }
+
+ public static double GetNumericValue(String s, int index)
+ {
+ if (s == null)
+ throw new ArgumentNullException(nameof(s));
+ if (((uint)index) >= ((uint)s.Length))
+ {
+ throw new ArgumentOutOfRangeException(nameof(index));
+ }
+ Contract.EndContractBlock();
+ return CharUnicodeInfo.GetNumericValue(s, index);
+ }
+
+
+ /*================================= IsHighSurrogate ============================
+ ** Check if a char is a high surrogate.
+ ==============================================================================*/
+ [Pure]
+ public static bool IsHighSurrogate(char c)
+ {
+ return ((c >= CharUnicodeInfo.HIGH_SURROGATE_START) && (c <= CharUnicodeInfo.HIGH_SURROGATE_END));
+ }
+
+ [Pure]
+ public static bool IsHighSurrogate(String s, int index)
+ {
+ if (s == null)
+ {
+ throw new ArgumentNullException(nameof(s));
+ }
+ if (index < 0 || index >= s.Length)
+ {
+ throw new ArgumentOutOfRangeException(nameof(index));
+ }
+ Contract.EndContractBlock();
+ return (IsHighSurrogate(s[index]));
+ }
+
+ /*================================= IsLowSurrogate ============================
+ ** Check if a char is a low surrogate.
+ ==============================================================================*/
+ [Pure]
+ public static bool IsLowSurrogate(char c)
+ {
+ return ((c >= CharUnicodeInfo.LOW_SURROGATE_START) && (c <= CharUnicodeInfo.LOW_SURROGATE_END));
+ }
+
+ [Pure]
+ public static bool IsLowSurrogate(String s, int index)
+ {
+ if (s == null)
+ {
+ throw new ArgumentNullException(nameof(s));
+ }
+ if (index < 0 || index >= s.Length)
+ {
+ throw new ArgumentOutOfRangeException(nameof(index));
+ }
+ Contract.EndContractBlock();
+ return (IsLowSurrogate(s[index]));
+ }
+
+ /*================================= IsSurrogatePair ============================
+ ** Check if the string specified by the index starts with a surrogate pair.
+ ==============================================================================*/
+ [Pure]
+ public static bool IsSurrogatePair(String s, int index)
+ {
+ if (s == null)
+ {
+ throw new ArgumentNullException(nameof(s));
+ }
+ if (index < 0 || index >= s.Length)
+ {
+ throw new ArgumentOutOfRangeException(nameof(index));
+ }
+ Contract.EndContractBlock();
+ if (index + 1 < s.Length)
+ {
+ return (IsSurrogatePair(s[index], s[index + 1]));
+ }
+ return (false);
+ }
+
+ [Pure]
+ public static bool IsSurrogatePair(char highSurrogate, char lowSurrogate)
+ {
+ return ((highSurrogate >= CharUnicodeInfo.HIGH_SURROGATE_START && highSurrogate <= CharUnicodeInfo.HIGH_SURROGATE_END) &&
+ (lowSurrogate >= CharUnicodeInfo.LOW_SURROGATE_START && lowSurrogate <= CharUnicodeInfo.LOW_SURROGATE_END));
+ }
+
+ internal const int UNICODE_PLANE00_END = 0x00ffff;
+ // The starting codepoint for Unicode plane 1. Plane 1 contains 0x010000 ~ 0x01ffff.
+ internal const int UNICODE_PLANE01_START = 0x10000;
+ // The end codepoint for Unicode plane 16. This is the maximum code point value allowed for Unicode.
+ // Plane 16 contains 0x100000 ~ 0x10ffff.
+ internal const int UNICODE_PLANE16_END = 0x10ffff;
+
+ internal const int HIGH_SURROGATE_START = 0x00d800;
+ internal const int LOW_SURROGATE_END = 0x00dfff;
+
+
+
+ /*================================= ConvertFromUtf32 ============================
+ ** Convert an UTF32 value into a surrogate pair.
+ ==============================================================================*/
+
+ public static String ConvertFromUtf32(int utf32)
+ {
+ // For UTF32 values from U+00D800 ~ U+00DFFF, we should throw. They
+ // are considered as irregular code unit sequence, but they are not illegal.
+ if ((utf32 < 0 || utf32 > UNICODE_PLANE16_END) || (utf32 >= HIGH_SURROGATE_START && utf32 <= LOW_SURROGATE_END))
+ {
+ throw new ArgumentOutOfRangeException(nameof(utf32), SR.ArgumentOutOfRange_InvalidUTF32);
+ }
+ Contract.EndContractBlock();
+
+ if (utf32 < UNICODE_PLANE01_START)
+ {
+ // This is a BMP character.
+ return (Char.ToString((char)utf32));
+ }
+
+ unsafe
+ {
+ // This is a supplementary character. Convert it to a surrogate pair in UTF-16.
+ utf32 -= UNICODE_PLANE01_START;
+ uint surrogate = 0; // allocate 2 chars worth of stack space
+ char* address = (char*)&surrogate;
+ address[0] = (char)((utf32 / 0x400) + (int)CharUnicodeInfo.HIGH_SURROGATE_START);
+ address[1] = (char)((utf32 % 0x400) + (int)CharUnicodeInfo.LOW_SURROGATE_START);
+ return new string(address, 0, 2);
+ }
+ }
+
+
+ /*=============================ConvertToUtf32===================================
+ ** Convert a surrogate pair to UTF32 value
+ ==============================================================================*/
+
+ public static int ConvertToUtf32(char highSurrogate, char lowSurrogate)
+ {
+ if (!IsHighSurrogate(highSurrogate))
+ {
+ throw new ArgumentOutOfRangeException(nameof(highSurrogate), SR.ArgumentOutOfRange_InvalidHighSurrogate);
+ }
+ if (!IsLowSurrogate(lowSurrogate))
+ {
+ throw new ArgumentOutOfRangeException(nameof(lowSurrogate), SR.ArgumentOutOfRange_InvalidLowSurrogate);
+ }
+ Contract.EndContractBlock();
+ return (((highSurrogate - CharUnicodeInfo.HIGH_SURROGATE_START) * 0x400) + (lowSurrogate - CharUnicodeInfo.LOW_SURROGATE_START) + UNICODE_PLANE01_START);
+ }
+
+ /*=============================ConvertToUtf32===================================
+ ** Convert a character or a surrogate pair starting at index of the specified string
+ ** to UTF32 value.
+ ** The char pointed by index should be a surrogate pair or a BMP character.
+ ** This method throws if a high-surrogate is not followed by a low surrogate.
+ ** This method throws if a low surrogate is seen without preceding a high-surrogate.
+ ==============================================================================*/
+
+ public static int ConvertToUtf32(String s, int index)
+ {
+ if (s == null)
+ {
+ throw new ArgumentNullException(nameof(s));
+ }
+
+ if (index < 0 || index >= s.Length)
+ {
+ throw new ArgumentOutOfRangeException(nameof(index), SR.ArgumentOutOfRange_Index);
+ }
+ Contract.EndContractBlock();
+ // Check if the character at index is a high surrogate.
+ int temp1 = (int)s[index] - CharUnicodeInfo.HIGH_SURROGATE_START;
+ if (temp1 >= 0 && temp1 <= 0x7ff)
+ {
+ // Found a surrogate char.
+ if (temp1 <= 0x3ff)
+ {
+ // Found a high surrogate.
+ if (index < s.Length - 1)
+ {
+ int temp2 = (int)s[index + 1] - CharUnicodeInfo.LOW_SURROGATE_START;
+ if (temp2 >= 0 && temp2 <= 0x3ff)
+ {
+ // Found a low surrogate.
+ return ((temp1 * 0x400) + temp2 + UNICODE_PLANE01_START);
+ }
+ else
+ {
+ throw new ArgumentException(SR.Format(SR.Argument_InvalidHighSurrogate, index), nameof(s));
+ }
+ }
+ else
+ {
+ // Found a high surrogate at the end of the string.
+ throw new ArgumentException(SR.Format(SR.Argument_InvalidHighSurrogate, index), nameof(s));
+ }
+ }
+ else
+ {
+ // Find a low surrogate at the character pointed by index.
+ throw new ArgumentException(SR.Format(SR.Argument_InvalidLowSurrogate, index), nameof(s));
+ }
+ }
+ // Not a high-surrogate or low-surrogate. Genereate the UTF32 value for the BMP characters.
+ return ((int)s[index]);
+ }
+ }
+}