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//------------------------------------------------------------------------------
// <copyright file="SQLBoolean.cs" company="Microsoft">
// Copyright (c) Microsoft Corporation. All rights reserved.
// </copyright>
// <owner current="true" primary="true">junfang</owner>
// <owner current="true" primary="false">Microsoft</owner>
// <owner current="true" primary="false">Microsoft</owner>
//------------------------------------------------------------------------------
//**************************************************************************
// @File: SqlBoolean.cs
//
// Create by: JunFang
//
// Purpose: Implementation of SqlBoolean which is equivalent to
// data type "bit" in SQL Server
//
// Notes:
//
// History:
//
// 09/17/99 JunFang Created and implemented as first drop.
//
// @EndHeader@
//**************************************************************************
using System;
using System.Data.Common;
using System.Runtime.InteropServices;
using System.Globalization;
using System.Xml;
using System.Xml.Schema;
using System.Xml.Serialization;
namespace System.Data.SqlTypes {
/// <devdoc>
/// <para>
/// Represents an integer value that is either 1 or 0.
/// </para>
/// </devdoc>
[Serializable]
[StructLayout(LayoutKind.Sequential)]
[XmlSchemaProvider("GetXsdType")]
public struct SqlBoolean : INullable, IComparable, IXmlSerializable {
// m_value: 2 (true), 1 (false), 0 (unknown/Null)
private byte m_value;
private const byte x_Null = 0;
private const byte x_False = 1;
private const byte x_True = 2;
// constructor
/// <devdoc>
/// <para>
/// Initializes a new instance of the <see cref='System.Data.SqlTypes.SqlBoolean'/> class.
/// </para>
/// </devdoc>
public SqlBoolean(bool value) {
m_value = (byte)(value ? x_True : x_False);
}
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public SqlBoolean(int value) : this(value, false) {
}
private SqlBoolean(int value, bool fNull) {
if (fNull)
m_value = x_Null;
else
m_value = (value != 0) ? x_True : x_False;
}
// INullable
/// <devdoc>
/// <para>
/// Gets whether the current <see cref='System.Data.SqlTypes.SqlBoolean.Value'/> is <see cref='System.Data.SqlTypes.SqlBoolean.Null'/>.
/// </para>
/// </devdoc>
public bool IsNull {
get { return m_value == x_Null;}
}
// property: Value
/// <devdoc>
/// <para>
/// Gets or sets the <see cref='System.Data.SqlTypes.SqlBoolean'/> to be <see langword='true'/> or
/// <see langword='false'/>.
/// </para>
/// </devdoc>
public bool Value {
get {
switch (m_value) {
case x_True:
return true;
case x_False:
return false;
default:
throw new SqlNullValueException();
}
}
}
// property: IsTrue
/// <devdoc>
/// <para>
/// Gets whether the current <see cref='System.Data.SqlTypes.SqlBoolean.Value'/> is <see cref='System.Data.SqlTypes.SqlBoolean.True'/>.
/// </para>
/// </devdoc>
public bool IsTrue {
get { return m_value == x_True;}
}
// property: IsFalse
/// <devdoc>
/// <para>
/// Gets whether the current <see cref='System.Data.SqlTypes.SqlBoolean.Value'/> is <see cref='System.Data.SqlTypes.SqlBoolean.False'/>.
/// </para>
/// </devdoc>
public bool IsFalse {
get { return m_value == x_False;}
}
// Implicit conversion from bool to SqlBoolean
/// <devdoc>
/// <para>
/// Converts a boolean to a <see cref='System.Data.SqlTypes.SqlBoolean'/>.
/// </para>
/// </devdoc>
public static implicit operator SqlBoolean(bool x) {
return new SqlBoolean(x);
}
// Explicit conversion from SqlBoolean to bool. Throw exception if x is Null.
/// <devdoc>
/// <para>
/// Converts a <see cref='System.Data.SqlTypes.SqlBoolean'/>
/// to a boolean.
/// </para>
/// </devdoc>
public static explicit operator bool(SqlBoolean x) {
return x.Value;
}
// Unary operators
/// <devdoc>
/// <para>
/// Performs a NOT operation on a <see cref='System.Data.SqlTypes.SqlBoolean'/>
/// .
/// </para>
/// </devdoc>
public static SqlBoolean operator !(SqlBoolean x) {
switch (x.m_value) {
case x_True:
return SqlBoolean.False;
case x_False:
return SqlBoolean.True;
default:
SQLDebug.Check(x.m_value == x_Null);
return SqlBoolean.Null;
}
}
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public static bool operator true(SqlBoolean x) {
return x.IsTrue;
}
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public static bool operator false(SqlBoolean x) {
return x.IsFalse;
}
// Binary operators
/// <devdoc>
/// <para>
/// Performs a bitwise AND operation on two instances of
/// <see cref='System.Data.SqlTypes.SqlBoolean'/>
/// .
/// </para>
/// </devdoc>
public static SqlBoolean operator &(SqlBoolean x, SqlBoolean y) {
if (x.m_value == x_False || y.m_value == x_False)
return SqlBoolean.False;
else if (x.m_value == x_True && y.m_value == x_True)
return SqlBoolean.True;
else
return SqlBoolean.Null;
}
/// <devdoc>
/// <para>
/// Performs
/// a bitwise OR operation on two instances of a
/// <see cref='System.Data.SqlTypes.SqlBoolean'/>
/// .
/// </para>
/// </devdoc>
public static SqlBoolean operator |(SqlBoolean x, SqlBoolean y) {
if (x.m_value == x_True || y.m_value == x_True)
return SqlBoolean.True;
else if (x.m_value == x_False && y.m_value == x_False)
return SqlBoolean.False;
else
return SqlBoolean.Null;
}
// property: ByteValue
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public byte ByteValue {
get {
if (!IsNull)
return (m_value == x_True) ? (byte)1 : (byte)0;
else
throw new SqlNullValueException();
}
}
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public override String ToString() {
return IsNull ? SQLResource.NullString : Value.ToString((IFormatProvider)null);
}
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public static SqlBoolean Parse(String s) {
if (null == s)
// Let Boolean.Parse throw exception
return new SqlBoolean(Boolean.Parse(s));
if (s == SQLResource.NullString)
return SqlBoolean.Null;
s = s.TrimStart();
char wchFirst = s[0];
if (Char.IsNumber(wchFirst) || ('-' == wchFirst) || ('+' == wchFirst)) {
return new SqlBoolean(Int32.Parse(s, (IFormatProvider)null));
}
else {
return new SqlBoolean(Boolean.Parse(s));
}
}
// Unary operators
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public static SqlBoolean operator ~(SqlBoolean x) {
return (!x);
}
// Binary operators
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public static SqlBoolean operator ^(SqlBoolean x, SqlBoolean y) {
return(x.IsNull || y.IsNull) ? Null : new SqlBoolean(x.m_value != y.m_value);
}
// Implicit conversions
// Explicit conversions
// Explicit conversion from SqlByte to SqlBoolean
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public static explicit operator SqlBoolean(SqlByte x) {
return x.IsNull ? Null : new SqlBoolean(x.Value != 0);
}
// Explicit conversion from SqlInt16 to SqlBoolean
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public static explicit operator SqlBoolean(SqlInt16 x) {
return x.IsNull ? Null : new SqlBoolean(x.Value != 0);
}
// Explicit conversion from SqlInt32 to SqlBoolean
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public static explicit operator SqlBoolean(SqlInt32 x) {
return x.IsNull ? Null : new SqlBoolean(x.Value != 0);
}
// Explicit conversion from SqlInt64 to SqlBoolean
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public static explicit operator SqlBoolean(SqlInt64 x) {
return x.IsNull ? Null : new SqlBoolean(x.Value != 0);
}
// Explicit conversion from SqlDouble to SqlBoolean
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public static explicit operator SqlBoolean(SqlDouble x) {
return x.IsNull ? Null : new SqlBoolean(x.Value != 0.0);
}
// Explicit conversion from SqlSingle to SqlBoolean
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public static explicit operator SqlBoolean(SqlSingle x) {
return x.IsNull ? Null : new SqlBoolean(x.Value != 0.0);
}
// Explicit conversion from SqlMoney to SqlBoolean
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public static explicit operator SqlBoolean(SqlMoney x) {
return x.IsNull ? Null : (x != SqlMoney.Zero);
}
// Explicit conversion from SqlDecimal to SqlBoolean
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public static explicit operator SqlBoolean(SqlDecimal x) {
return x.IsNull ? SqlBoolean.Null : new SqlBoolean(x.m_data1 != 0 || x.m_data2 != 0 ||
x.m_data3 != 0 || x.m_data4 != 0);
}
// Explicit conversion from SqlString to SqlBoolean
// Throws FormatException or OverflowException if necessary.
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public static explicit operator SqlBoolean(SqlString x) {
return x.IsNull ? Null : SqlBoolean.Parse(x.Value);
}
// Overloading comparison operators
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public static SqlBoolean operator==(SqlBoolean x, SqlBoolean y) {
return(x.IsNull || y.IsNull) ? SqlBoolean.Null : new SqlBoolean(x.m_value == y.m_value);
}
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public static SqlBoolean operator!=(SqlBoolean x, SqlBoolean y) {
return ! (x == y);
}
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public static SqlBoolean operator<(SqlBoolean x, SqlBoolean y) {
return(x.IsNull || y.IsNull) ? SqlBoolean.Null : new SqlBoolean(x.m_value < y.m_value);
}
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public static SqlBoolean operator>(SqlBoolean x, SqlBoolean y) {
return(x.IsNull || y.IsNull) ? SqlBoolean.Null : new SqlBoolean(x.m_value > y.m_value);
}
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public static SqlBoolean operator<=(SqlBoolean x, SqlBoolean y) {
return(x.IsNull || y.IsNull) ? SqlBoolean.Null : new SqlBoolean(x.m_value <= y.m_value);
}
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public static SqlBoolean operator>=(SqlBoolean x, SqlBoolean y) {
return(x.IsNull || y.IsNull) ? SqlBoolean.Null : new SqlBoolean(x.m_value >= y.m_value);
}
//--------------------------------------------------
// Alternative methods for overloaded operators
//--------------------------------------------------
// Alternative method for operator ~
public static SqlBoolean OnesComplement(SqlBoolean x) {
return ~x;
}
// Alternative method for operator &
public static SqlBoolean And(SqlBoolean x, SqlBoolean y) {
return x & y;
}
// Alternative method for operator |
public static SqlBoolean Or(SqlBoolean x, SqlBoolean y) {
return x | y;
}
// Alternative method for operator ^
public static SqlBoolean Xor(SqlBoolean x, SqlBoolean y) {
return x ^ y;
}
// Alternative method for operator ==
public static SqlBoolean Equals(SqlBoolean x, SqlBoolean y) {
return (x == y);
}
// Alternative method for operator !=
public static SqlBoolean NotEquals(SqlBoolean x, SqlBoolean y) {
return (x != y);
}
// Alternative method for operator >
public static SqlBoolean GreaterThan(SqlBoolean x, SqlBoolean y) {
return (x > y);
}
// Alternative method for operator <
public static SqlBoolean LessThan(SqlBoolean x, SqlBoolean y) {
return (x < y);
}
// Alternative method for operator <=
public static SqlBoolean GreaterThanOrEquals(SqlBoolean x, SqlBoolean y) {
return (x >= y);
}
// Alternative method for operator !=
public static SqlBoolean LessThanOrEquals(SqlBoolean x, SqlBoolean y) {
return (x <= y);
}
// Alternative method for conversions.
public SqlByte ToSqlByte() {
return (SqlByte)this;
}
public SqlDouble ToSqlDouble() {
return (SqlDouble)this;
}
public SqlInt16 ToSqlInt16() {
return (SqlInt16)this;
}
public SqlInt32 ToSqlInt32() {
return (SqlInt32)this;
}
public SqlInt64 ToSqlInt64() {
return (SqlInt64)this;
}
public SqlMoney ToSqlMoney() {
return (SqlMoney)this;
}
public SqlDecimal ToSqlDecimal() {
return (SqlDecimal)this;
}
public SqlSingle ToSqlSingle() {
return (SqlSingle)this;
}
public SqlString ToSqlString() {
return (SqlString)this;
}
// IComparable
// Compares this object to another object, returning an integer that
// indicates the relationship.
// Returns a value less than zero if this < object, zero if this = object,
// or a value greater than zero if this > object.
// null is considered to be less than any instance.
// If object is not of same type, this method throws an ArgumentException.
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public int CompareTo(Object value) {
if (value is SqlBoolean) {
SqlBoolean i = (SqlBoolean)value;
return CompareTo(i);
}
throw ADP.WrongType(value.GetType(), typeof(SqlBoolean));
}
public int CompareTo(SqlBoolean value) {
// If both Null, consider them equal.
// Otherwise, Null is less than anything.
if (IsNull)
return value.IsNull ? 0 : -1;
else if (value.IsNull)
return 1;
if (this.ByteValue < value.ByteValue) return -1;
if (this.ByteValue > value.ByteValue) return 1;
return 0;
}
// Compares this instance with a specified object
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public override bool Equals(Object value) {
if (!(value is SqlBoolean)) {
return false;
}
SqlBoolean i = (SqlBoolean)value;
if (i.IsNull || IsNull)
return (i.IsNull && IsNull);
else
return (this == i).Value;
}
// For hashing purpose
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public override int GetHashCode() {
return IsNull ? 0 : Value.GetHashCode();
}
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
XmlSchema IXmlSerializable.GetSchema() { return null; }
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
void IXmlSerializable.ReadXml(XmlReader reader) {
string isNull = reader.GetAttribute("nil", XmlSchema.InstanceNamespace);
if (isNull != null && XmlConvert.ToBoolean(isNull)) {
// VSTFDevDiv# 479603 - SqlTypes read null value infinitely and never read the next value. Fix - Read the next value.
reader.ReadElementString();
m_value = x_Null;
}
else {
m_value = (byte)(XmlConvert.ToBoolean(reader.ReadElementString()) ? x_True : x_False);
}
}
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
void IXmlSerializable.WriteXml(XmlWriter writer) {
if (IsNull) {
writer.WriteAttributeString("xsi", "nil", XmlSchema.InstanceNamespace, "true");
}
else {
writer.WriteString(m_value == x_True ? "true" : "false");
}
}
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public static XmlQualifiedName GetXsdType(XmlSchemaSet schemaSet) {
return new XmlQualifiedName("boolean", XmlSchema.Namespace);
}
/// <devdoc>
/// <para>
/// Represents a true value that can be assigned to the
/// <see cref='System.Data.SqlTypes.SqlBoolean.Value'/> property of an instance of
/// the <see cref='System.Data.SqlTypes.SqlBoolean'/> class.
/// </para>
/// </devdoc>
public static readonly SqlBoolean True = new SqlBoolean(true);
/// <devdoc>
/// <para>
/// Represents a false value that can be assigned to the
/// <see cref='System.Data.SqlTypes.SqlBoolean.Value'/> property of an instance of
/// the <see cref='System.Data.SqlTypes.SqlBoolean'/> class.
/// </para>
/// </devdoc>
public static readonly SqlBoolean False = new SqlBoolean(false);
/// <devdoc>
/// <para>
/// Represents a null value that can be assigned to the <see cref='System.Data.SqlTypes.SqlBoolean.Value'/> property of an instance of
/// the <see cref='System.Data.SqlTypes.SqlBoolean'/> class.
/// </para>
/// </devdoc>
public static readonly SqlBoolean Null = new SqlBoolean(0, true);
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public static readonly SqlBoolean Zero = new SqlBoolean(0);
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public static readonly SqlBoolean One = new SqlBoolean(1);
} // SqlBoolean
} // namespace System.Data.SqlTypes
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