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// 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.
//
using System;
using System.IO;
using System.ComponentModel;
using System.ComponentModel.Design.Serialization;
using System.Reflection;
using MS.Internal;
using System.Windows.Media;
using System.Text;
using System.Collections;
using System.Globalization;
using System.Runtime.InteropServices;
using System.Security;
using System.Net.Cache;
using SR=MS.Internal.PresentationCore.SR;
namespace System.Windows.Media
{
/// <summary>
/// RequestCachePolicyConverter Parses a RequestCachePolicy.
/// </summary>
public sealed class RequestCachePolicyConverter : TypeConverter
{
/// <summary>
/// CanConvertFrom
/// </summary>
public override bool CanConvertFrom(ITypeDescriptorContext td, Type t)
{
if (t == typeof(string))
{
return true;
}
else
{
return false;
}
}
/// <summary>
/// CanConvertTo - Returns whether or not this class can convert to a given type.
/// </summary>
/// <returns>
/// bool - True if this converter can convert to the provided type, false if not.
/// </returns>
/// <param name="typeDescriptorContext"> The ITypeDescriptorContext for this call. </param>
/// <param name="destinationType"> The Type being queried for support. </param>
public override bool CanConvertTo(ITypeDescriptorContext typeDescriptorContext, Type destinationType)
{
// We can convert to an InstanceDescriptor or to a string.
if (destinationType == typeof(InstanceDescriptor) ||
destinationType == typeof(string))
{
return true;
}
else
{
return false;
}
}
/// <summary>
/// ConvertFrom - attempt to convert to a RequestCachePolicy from the given object
/// </summary>
/// <exception cref="NotSupportedException">
/// A NotSupportedException is thrown if the example object is null or is not a valid type
/// which can be converted to a RequestCachePolicy.
/// </exception>
public override object ConvertFrom(ITypeDescriptorContext td, System.Globalization.CultureInfo ci, object value)
{
if (null == value)
{
throw GetConvertFromException(value);
}
string s = value as string;
if (null == s)
{
throw new ArgumentException(SR.Format(SR.General_BadType, "ConvertFrom"), "value");
}
HttpRequestCacheLevel level = Enum.Parse<HttpRequestCacheLevel>(s, true);
return new HttpRequestCachePolicy(level);
}
/// <summary>
/// ConvertTo - Attempt to convert to the given type
/// </summary>
/// <returns>
/// The object which was constructed.
/// </returns>
/// <exception cref="ArgumentNullException">
/// An ArgumentNullException is thrown if the example object is null.
/// </exception>
/// <exception cref="ArgumentException">
/// An ArgumentException is thrown if the object is not null,
/// or if the destinationType isn't one of the valid destination types.
/// </exception>
/// <param name="typeDescriptorContext"> The ITypeDescriptorContext for this call. </param>
/// <param name="cultureInfo"> The CultureInfo which is respected when converting. </param>
/// <param name="value"> The policy to convert. </param>
/// <param name="destinationType">The type to which to convert the policy. </param>
public override object ConvertTo(ITypeDescriptorContext typeDescriptorContext,
CultureInfo cultureInfo,
object value,
Type destinationType)
{
ArgumentNullException.ThrowIfNull(destinationType);
HttpRequestCachePolicy httpPolicy = value as HttpRequestCachePolicy;
if(httpPolicy != null)
{
if (destinationType == typeof(string))
{
return httpPolicy.Level.ToString();
}
else if (destinationType == typeof(InstanceDescriptor))
{
ConstructorInfo ci = typeof(HttpRequestCachePolicy).GetConstructor(new Type[] { typeof(HttpRequestCachePolicy) });
return new InstanceDescriptor(ci, new object[] { httpPolicy.Level });
}
}
//if it's not an HttpRequestCachePolicy, try a regular RequestCachePolicy
RequestCachePolicy policy = value as RequestCachePolicy;
if (policy != null)
{
if (destinationType == typeof(string))
{
return policy.Level.ToString();
}
else if (destinationType == typeof(InstanceDescriptor))
{
ConstructorInfo ci = typeof(RequestCachePolicy).GetConstructor(new Type[] { typeof(RequestCachePolicy) });
return new InstanceDescriptor(ci, new object[] { policy.Level });
}
}
throw GetConvertToException(value, destinationType);
}
}
}
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