// ==++==
//
//
// Copyright (c) 2006 Microsoft Corporation. All rights reserved.
//
// The use and distribution terms for this software are contained in the file
// named license.txt, which can be found in the root of this distribution.
// By using this software in any fashion, you are agreeing to be bound by the
// terms of this license.
//
// You must not remove this notice, or any other, from this software.
//
//
// ==--==
/*============================================================
**
** Class: Boolean
**
**
** Purpose: The boolean class serves as a wrapper for the primitive
** type boolean.
**
**
===========================================================*/
namespace System {
using System;
using System.Globalization;
// The Boolean class provides the
// object representation of the boolean primitive type.
[Serializable()]
[System.Runtime.InteropServices.ComVisible(true)]
public struct Boolean : IComparable, IConvertible
, IComparable<Boolean>, IEquatable<Boolean>
{
//
// Member Variables
//
private bool m_value;
private static char[] m_trimmableChars;
// The true value.
//
internal const int True = 1;
// The false value.
//
internal const int False = 0;
//
// Internal Constants are real consts for performance.
//
// The internal string representation of true.
//
internal const String TrueLiteral = "True";
// The internal string representation of false.
//
internal const String FalseLiteral = "False";
//
// Public Constants
//
// The public string representation of true.
//
public static readonly String TrueString = TrueLiteral;
// The public string representation of false.
//
public static readonly String FalseString = FalseLiteral;
//
// Overriden Instance Methods
//
/*=================================GetHashCode==================================
**Args: None
**Returns: 1 or 0 depending on whether this instance represents true or false.
**Exceptions: None
**Overriden From: Value
==============================================================================*/
// Provides a hash code for this instance.
public override int GetHashCode() {
return (m_value)?True:False;
}
/*===================================ToString===================================
**Args: None
**Returns: "True" or "False" depending on the state of the boolean.
**Exceptions: None.
==============================================================================*/
// Converts the boolean value of this instance to a String.
public override String ToString() {
if (false == m_value) {
return FalseLiteral;
}
return TrueLiteral;
}
public String ToString(IFormatProvider provider) {
if (false == m_value) {
return FalseLiteral;
}
return TrueLiteral;
}
// Determines whether two Boolean objects are equal.
public override bool Equals (Object obj) {
//If it's not a boolean, we're definitely not equal
if (!(obj is Boolean)) {
return false;
}
return (m_value==((Boolean)obj).m_value);
}
public bool Equals(Boolean obj)
{
return m_value == obj;
}
// Compares this object to another object, returning an integer that
// indicates the relationship. For booleans, false sorts before true.
// null is considered to be less than any instance.
// If object is not of type boolean, this method throws an ArgumentException.
//
// Returns a value less than zero if this object
//
public int CompareTo(Object obj) {
if (obj==null) {
return 1;
}
if (!(obj is Boolean)) {
throw new ArgumentException (Environment.GetResourceString("Arg_MustBeBoolean"));
}
if (m_value==((Boolean)obj).m_value) {
return 0;
} else if (m_value==false) {
return -1;
}
return 1;
}
public int CompareTo(Boolean value) {
if (m_value==value) {
return 0;
} else if (m_value==false) {
return -1;
}
return 1;
}
//
// Static Methods
//
// Determines whether a String represents true or false.
//
public static Boolean Parse (String value) {
if (value==null) throw new ArgumentNullException("value");
Boolean result = false;
if (!TryParse(value, out result)) {
throw new FormatException(Environment.GetResourceString("Format_BadBoolean"));
}
else {
return result;
}
}
// Determines whether a String represents true or false.
//
public static Boolean TryParse (String value, out Boolean result) {
result = false;
if (value==null) {
return false;
}
// For perf reasons, let's first see if they're equal, then do the
// trim to get rid of white space, and check again.
if (TrueLiteral.Equals(value, StringComparison.OrdinalIgnoreCase)) {
result = true;
return true;
}
if (FalseLiteral.Equals(value,StringComparison.OrdinalIgnoreCase)) {
result = false;
return true;
}
// Special case: Trim whitespace as well as null characters.
// Solution: Lazily initialize a new character array including 0x0000
if (null == m_trimmableChars)
{
char [] m_trimmableCharsTemp = new char[String.WhitespaceChars.Length + 1];
Array.Copy(String.WhitespaceChars, m_trimmableCharsTemp, String.WhitespaceChars.Length);
m_trimmableCharsTemp[m_trimmableCharsTemp.Length - 1] = (char) 0x0000;
m_trimmableChars = m_trimmableCharsTemp;
}
value = value.Trim(m_trimmableChars); // Remove leading & trailing white space.
if (TrueLiteral.Equals(value, StringComparison.OrdinalIgnoreCase)) {
result = true;
return true;
}
if (FalseLiteral.Equals(value,StringComparison.OrdinalIgnoreCase)) {
result = false;
return true;
}
return false;
}
//
// IValue implementation
//
public TypeCode GetTypeCode() {
return TypeCode.Boolean;
}
/// <internalonly/>
bool IConvertible.ToBoolean(IFormatProvider provider) {
return m_value;
}
/// <internalonly/>
char IConvertible.ToChar(IFormatProvider provider) {
throw new InvalidCastException(String.Format(CultureInfo.CurrentCulture, Environment.GetResourceString("InvalidCast_FromTo"), "Boolean", "Char"));
}
/// <internalonly/>
sbyte IConvertible.ToSByte(IFormatProvider provider) {
return Convert.ToSByte(m_value);
}
/// <internalonly/>
byte IConvertible.ToByte(IFormatProvider provider) {
return Convert.ToByte(m_value);
}
/// <internalonly/>
short IConvertible.ToInt16(IFormatProvider provider) {
return Convert.ToInt16(m_value);
}
/// <internalonly/>
ushort IConvertible.ToUInt16(IFormatProvider provider) {
return Convert.ToUInt16(m_value);
}
/// <internalonly/>
int IConvertible.ToInt32(IFormatProvider provider) {
return Convert.ToInt32(m_value);
}
/// <internalonly/>
uint IConvertible.ToUInt32(IFormatProvider provider) {
return Convert.ToUInt32(m_value);
}
/// <internalonly/>
long IConvertible.ToInt64(IFormatProvider provider) {
return Convert.ToInt64(m_value);
}
/// <internalonly/>
ulong IConvertible.ToUInt64(IFormatProvider provider) {
return Convert.ToUInt64(m_value);
}
/// <internalonly/>
float IConvertible.ToSingle(IFormatProvider provider) {
return Convert.ToSingle(m_value);
}
/// <internalonly/>
double IConvertible.ToDouble(IFormatProvider provider) {
return Convert.ToDouble(m_value);
}
/// <internalonly/>
Decimal IConvertible.ToDecimal(IFormatProvider provider) {
return Convert.ToDecimal(m_value);
}
/// <internalonly/>
DateTime IConvertible.ToDateTime(IFormatProvider provider) {
throw new InvalidCastException(String.Format(CultureInfo.CurrentCulture, Environment.GetResourceString("InvalidCast_FromTo"), "Boolean", "DateTime"));
}
/// <internalonly/>
Object IConvertible.ToType(Type type, IFormatProvider provider) {
return Convert.DefaultToType((IConvertible)this, type, provider);
}
}
}
