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//------------------------------------------------------------------------------
// <copyright file="SqlGuid.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: SqlGuid.cs
//
// Create by: JunFang
//
// Purpose: Implementation of SqlGuid which is equivalent to
// data type "uniqueidentifier" in SQL Server
//
// Notes:
//
// History:
//
// 11/1/99 JunFang Created.
//
// @EndHeader@
//**************************************************************************
using System;
using System.Data.Common;
using System.Xml;
using System.Xml.Schema;
using System.Xml.Serialization;
namespace System.Data.SqlTypes {
/// <devdoc>
/// <para>
/// Represents a globally unique identifier to be stored in
/// or retrieved from a database.
/// </para>
/// </devdoc>
[Serializable]
[XmlSchemaProvider("GetXsdType")]
public struct SqlGuid : INullable, IComparable, IXmlSerializable {
private const int SizeOfGuid = 16;
// Comparison orders.
private static readonly int[] x_rgiGuidOrder = new int[16]
{10, 11, 12, 13, 14, 15, 8, 9, 6, 7, 4, 5, 0, 1, 2, 3};
private byte[] m_value; // the SqlGuid is null if m_value is null
// constructor
// construct a SqlGuid.Null
private SqlGuid(bool fNull) {
m_value = null;
}
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public SqlGuid(byte[] value) {
if (value == null || value.Length != SizeOfGuid)
throw new ArgumentException(SQLResource.InvalidArraySizeMessage);
m_value = new byte[SizeOfGuid];
value.CopyTo(m_value, 0);
}
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
internal SqlGuid(byte[] value, bool ignored) {
if (value == null || value.Length != SizeOfGuid)
throw new ArgumentException(SQLResource.InvalidArraySizeMessage);
m_value = value;
}
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public SqlGuid(String s) {
m_value = (new Guid(s)).ToByteArray();
}
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public SqlGuid(Guid g) {
m_value = g.ToByteArray();
}
public SqlGuid(int a, short b, short c, byte d, byte e, byte f, byte g, byte h, byte i, byte j, byte k)
: this(new Guid(a, b, c, d, e, f, g, h, i, j, k))
{
}
// INullable
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public bool IsNull {
get { return(m_value == null);}
}
// property: Value
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public Guid Value {
get {
if (IsNull)
throw new SqlNullValueException();
else
return new Guid(m_value);
}
}
// Implicit conversion from Guid to SqlGuid
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public static implicit operator SqlGuid(Guid x) {
return new SqlGuid(x);
}
// Explicit conversion from SqlGuid to Guid. Throw exception if x is Null.
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public static explicit operator Guid(SqlGuid x) {
return x.Value;
}
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public byte[] ToByteArray() {
byte[] ret = new byte[SizeOfGuid];
m_value.CopyTo(ret, 0);
return ret;
}
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public override String ToString() {
if (IsNull)
return SQLResource.NullString;
Guid g = new Guid(m_value);
return g.ToString();
}
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public static SqlGuid Parse(String s) {
if (s == SQLResource.NullString)
return SqlGuid.Null;
else
return new SqlGuid(s);
}
// Comparison operators
private static EComparison Compare(SqlGuid x, SqlGuid y) {
//Swap to the correct order to be compared
for (int i = 0; i < SizeOfGuid; i++) {
byte b1, b2;
b1 = x.m_value [x_rgiGuidOrder[i]];
b2 = y.m_value [x_rgiGuidOrder[i]];
if (b1 != b2)
return(b1 < b2) ? EComparison.LT : EComparison.GT;
}
return EComparison.EQ;
}
// Implicit conversions
// Explicit conversions
// Explicit conversion from SqlString to SqlGuid
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public static explicit operator SqlGuid(SqlString x) {
return x.IsNull ? Null : new SqlGuid(x.Value);
}
// Explicit conversion from SqlBinary to SqlGuid
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public static explicit operator SqlGuid(SqlBinary x) {
return x.IsNull ? Null : new SqlGuid(x.Value);
}
// Overloading comparison operators
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public static SqlBoolean operator==(SqlGuid x, SqlGuid y) {
return(x.IsNull || y.IsNull) ? SqlBoolean.Null : new SqlBoolean(Compare(x, y) == EComparison.EQ);
}
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public static SqlBoolean operator!=(SqlGuid x, SqlGuid y) {
return ! (x == y);
}
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public static SqlBoolean operator<(SqlGuid x, SqlGuid y) {
return(x.IsNull || y.IsNull) ? SqlBoolean.Null : new SqlBoolean(Compare(x, y) == EComparison.LT);
}
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public static SqlBoolean operator>(SqlGuid x, SqlGuid y) {
return(x.IsNull || y.IsNull) ? SqlBoolean.Null : new SqlBoolean(Compare(x, y) == EComparison.GT);
}
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public static SqlBoolean operator<=(SqlGuid x, SqlGuid y) {
if (x.IsNull || y.IsNull)
return SqlBoolean.Null;
EComparison cmp = Compare(x, y);
return new SqlBoolean(cmp == EComparison.LT || cmp == EComparison.EQ);
}
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public static SqlBoolean operator>=(SqlGuid x, SqlGuid y) {
if (x.IsNull || y.IsNull)
return SqlBoolean.Null;
EComparison cmp = Compare(x, y);
return new SqlBoolean(cmp == EComparison.GT || cmp == EComparison.EQ);
}
//--------------------------------------------------
// Alternative methods for overloaded operators
//--------------------------------------------------
// Alternative method for operator ==
public static SqlBoolean Equals(SqlGuid x, SqlGuid y) {
return (x == y);
}
// Alternative method for operator !=
public static SqlBoolean NotEquals(SqlGuid x, SqlGuid y) {
return (x != y);
}
// Alternative method for operator <
public static SqlBoolean LessThan(SqlGuid x, SqlGuid y) {
return (x < y);
}
// Alternative method for operator >
public static SqlBoolean GreaterThan(SqlGuid x, SqlGuid y) {
return (x > y);
}
// Alternative method for operator <=
public static SqlBoolean LessThanOrEqual(SqlGuid x, SqlGuid y) {
return (x <= y);
}
// Alternative method for operator >=
public static SqlBoolean GreaterThanOrEqual(SqlGuid x, SqlGuid y) {
return (x >= y);
}
// Alternative method for conversions.
public SqlString ToSqlString() {
return (SqlString)this;
}
public SqlBinary ToSqlBinary() {
return (SqlBinary)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 SqlGuid) {
SqlGuid i = (SqlGuid)value;
return CompareTo(i);
}
throw ADP.WrongType(value.GetType(), typeof(SqlGuid));
}
public int CompareTo(SqlGuid 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 < value) return -1;
if (this > value) 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 SqlGuid)) {
return false;
}
SqlGuid i = (SqlGuid)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 = null;
}
else {
m_value = new Guid(reader.ReadElementString()).ToByteArray();
}
}
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
void IXmlSerializable.WriteXml(XmlWriter writer) {
if (IsNull) {
writer.WriteAttributeString("xsi", "nil", XmlSchema.InstanceNamespace, "true");
}
else {
writer.WriteString(XmlConvert.ToString(new Guid(m_value)));
}
}
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public static XmlQualifiedName GetXsdType(XmlSchemaSet schemaSet) {
return new XmlQualifiedName("string", XmlSchema.Namespace);
}
/// <devdoc>
/// <para>[To be supplied.]</para>
/// </devdoc>
public static readonly SqlGuid Null = new SqlGuid(true);
} // SqlGuid
} // namespace System.Data.SqlTypes
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