|
// 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.
// Description:
// The CriticalFileToken class ensures file represented is the one the
// user has authorized us to manipulate.
using System;
namespace MS.Internal.Documents.Application
{
/// <summary>
/// The CriticalFileToken class ensures file represented is the one the
/// user has authorized us to manipulate.
/// </summary>
/// <remarks>
/// Responsibility:
/// Allow XpsViewer to safely pass around information on which file the user
/// has authorized us to manipulate on thier behalf. Ensure that the creator
/// of the object has the privledge to manipulate the file represented.
///
/// Design Comments:
/// Many classes need to perform privledged operations files on behalf of the
/// user. However only DocObjHost and FilePresentation can assert it is user
/// sourced data.
///
/// As such we need them to create this 'token' which will will use as the only
/// source of authoritative information for which files we are manipulating.
/// </remarks>
internal sealed class CriticalFileToken
{
#region Constructors
//--------------------------------------------------------------------------
// Constructors
//--------------------------------------------------------------------------
internal CriticalFileToken(Uri location)
{
_location = location;
}
#endregion Constructors
#region Object Members
//--------------------------------------------------------------------------
// Object Members
//--------------------------------------------------------------------------
/// <summary>
/// Compares the values.
/// </summary>
/// <returns>True if they are equal.</returns>
public static bool operator ==(CriticalFileToken a, CriticalFileToken b)
{
bool result = false;
if (((object)a) == null)
{
if (((object)b) == null)
{
result = true;
}
}
else
{
if (((object)b) != null)
{
result = a._location.ToString().Equals(
b._location.ToString(),
StringComparison.OrdinalIgnoreCase);
}
}
return result;
}
/// <summary>
/// Compares the values.
/// </summary>
public static bool operator !=(CriticalFileToken a, CriticalFileToken b)
{
return !(a==b);
}
/// <summary>
/// Compares the values.
/// </summary>
public override bool Equals(object obj)
{
return (this == (obj as CriticalFileToken));
}
/// <summary>
/// See Object.GetHashCode();
/// </summary>
public override int GetHashCode()
{
return base.GetHashCode();
}
#endregion Object Members
#region Internal Properties
//--------------------------------------------------------------------------
// Internal Properties
//--------------------------------------------------------------------------
/// <summary>
/// The location for which the creator satisfied ReadWrite access.
/// </summary>
internal Uri Location
{
get
{
return _location;
}
}
#endregion Internal Properties
#region Private Fields
//--------------------------------------------------------------------------
// Private Fields
//--------------------------------------------------------------------------
private Uri _location;
#endregion Private Fields
}
}
|