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//---------------------------------------------------------------------------
//
// <copyright file="XmlNamespaceMapping.cs" company="Microsoft">
// Copyright (C) Microsoft Corporation. All rights reserved.
// </copyright>
//
// Description: Implementation of XmlNamespaceMapping object.
//
// Specs: http://avalon/connecteddata/M5%20Specs/XmlDataSource.mht
// http://avalon/connecteddata/M5%20Specs/WCP%20DataSources.mht
//
//---------------------------------------------------------------------------
using System;
using System.ComponentModel; // ISupportInitialize
namespace System.Windows.Data
{
/// <summary>
/// XmlNamespaceMapping Class
/// used for declaring Xml Namespace Mappings
/// </summary>
public class XmlNamespaceMapping : ISupportInitialize
{
/// <summary>
/// Constructor for XmlNamespaceMapping
/// </summary>
public XmlNamespaceMapping()
{
}
/// <summary>
/// Constructor for XmlNamespaceMapping
/// </summary>
public XmlNamespaceMapping(string prefix, Uri uri)
{
_prefix = prefix;
_uri = uri;
}
/// <summary>
/// The prefix to be used for this Namespace
/// </summary>
public string Prefix
{
get { return _prefix; }
set
{
if (!_initializing)
throw new InvalidOperationException(SR.Get(SRID.PropertyIsInitializeOnly, "Prefix", this.GetType().Name));
if (_prefix != null && _prefix != value)
throw new InvalidOperationException(SR.Get(SRID.PropertyIsImmutable, "Prefix", this.GetType().Name));
_prefix = value;
}
}
/// <summary>
/// The Uri to be used for this Namespace,
/// can be declared as an attribute or as the
/// TextContent of the XmlNamespaceMapping markup tag
/// </summary>
public Uri Uri
{
get { return _uri; }
set
{
if (!_initializing)
throw new InvalidOperationException(SR.Get(SRID.PropertyIsInitializeOnly, "Uri", this.GetType().Name));
if (_uri != null && _uri != value)
throw new InvalidOperationException(SR.Get(SRID.PropertyIsImmutable, "Uri", this.GetType().Name));
_uri = value;
}
}
/// <summary>
/// Equality comparison by value
/// </summary>
public override bool Equals(object obj)
{
return (this == (obj as XmlNamespaceMapping)); // call the == operator override
}
/// <summary>
/// Equality comparison by value
/// </summary>
public static bool operator == (XmlNamespaceMapping mappingA, XmlNamespaceMapping mappingB)
{
// cannot just compare with (mappingX == null), it'll cause recursion and stack overflow!
if (object.ReferenceEquals(mappingA, null))
return object.ReferenceEquals(mappingB, null);
if (object.ReferenceEquals(mappingB, null))
return false;
#pragma warning disable 1634, 1691
// presharp false positive for null-checking on mappings
#pragma warning suppress 56506
return ((mappingA.Prefix == mappingB.Prefix) && (mappingA.Uri == mappingB.Uri)) ;
#pragma warning restore 1634, 1691
}
/// <summary>
/// Inequality comparison by value
/// </summary>
public static bool operator != (XmlNamespaceMapping mappingA, XmlNamespaceMapping mappingB)
{
return !(mappingA == mappingB);
}
/// <summary>
/// Hash function for this type
/// </summary>
public override int GetHashCode()
{
// note that the hash code can change, but only during intialization
// (_prefix and _uri can only be changed once, from null to
// non-null, and only during [Begin/End]Init). Technically this is
// still a violation of the "constant during lifetime" rule, however
// in practice this is acceptable. It is very unlikely that someone
// will put an XmlNamespaceMapping into a hashtable before it is initialized.
int hash = 0;
if (_prefix != null)
hash = _prefix.GetHashCode();
if (_uri != null)
return unchecked(hash + _uri.GetHashCode());
else
return hash;
}
#region ISupportInitialize
/// <summary>Begin Initialization</summary>
void ISupportInitialize.BeginInit()
{
_initializing = true;
}
/// <summary>End Initialization, verify that internal state is consistent</summary>
void ISupportInitialize.EndInit()
{
if (_prefix == null)
{
throw new InvalidOperationException(SR.Get(SRID.PropertyMustHaveValue, "Prefix", this.GetType().Name));
}
if (_uri == null)
{
throw new InvalidOperationException(SR.Get(SRID.PropertyMustHaveValue, "Uri", this.GetType().Name));
}
_initializing = false;
}
#endregion ISupportInitialize
private string _prefix;
private Uri _uri;
private bool _initializing;
}
}
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