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//------------------------------------------------------------------------------
// Microsoft Windows Client Platform
// Copyright (c) Microsoft Corporation, 2004
//
// File: RepeatBehaviorConverter.cs
//------------------------------------------------------------------------------
using System;
using System.ComponentModel;
using System.ComponentModel.Design.Serialization;
using System.Diagnostics;
using System.Globalization;
using System.Reflection;
using System.Security;
namespace System.Windows.Media.Animation
{
/// <summary>
///
/// </summary>
public sealed class RepeatBehaviorConverter : TypeConverter
{
#region Data
private static char[] _iterationCharacter = new char[] { 'x' };
#endregion
/// <summary>
/// CanConvertFrom - Returns whether or not this class can convert from a given type
/// </summary>
/// <ExternalAPI/>
public override bool CanConvertFrom(ITypeDescriptorContext td, Type t)
{
if (t == typeof(string))
{
return true;
}
else
{
return false;
}
}
/// <summary>
/// TypeConverter method override.
/// </summary>
/// <param name="context">ITypeDescriptorContext</param>
/// <param name="destinationType">Type to convert to</param>
/// <returns>true if conversion is possible</returns>
/// <ExternalAPI/>
public override bool CanConvertTo(ITypeDescriptorContext context, Type destinationType)
{
if ( destinationType == typeof(InstanceDescriptor)
|| destinationType == typeof(string))
{
return true;
}
else
{
return false;
}
}
/// <summary>
/// ConvertFrom
/// </summary>
/// <ExternalAPI/>
public override object ConvertFrom(
ITypeDescriptorContext td,
CultureInfo cultureInfo,
object value)
{
string stringValue = value as string;
if (stringValue != null)
{
stringValue = stringValue.Trim();
if (stringValue == "Forever")
{
return RepeatBehavior.Forever;
}
else if ( stringValue.Length > 0
&& stringValue[stringValue.Length - 1] == _iterationCharacter[0])
{
string stringDoubleValue = stringValue.TrimEnd(_iterationCharacter);
double doubleValue = (double)TypeDescriptor.GetConverter(typeof(double)).ConvertFrom(td, cultureInfo, stringDoubleValue);
return new RepeatBehavior(doubleValue);
}
}
// The value is not Forever or an iteration count so it's either a TimeSpan
// or we'll let the TimeSpanConverter raise the appropriate exception.
TimeSpan timeSpanValue = (TimeSpan)TypeDescriptor.GetConverter(typeof(TimeSpan)).ConvertFrom(td, cultureInfo, stringValue);
return new RepeatBehavior(timeSpanValue);
}
/// <summary>
/// TypeConverter method implementation.
/// </summary>
/// <param name="context">ITypeDescriptorContext</param>
/// <param name="cultureInfo">current culture (see CLR specs)</param>
/// <param name="value">value to convert from</param>
/// <param name="destinationType">Type to convert to</param>
/// <returns>converted value</returns>
/// <ExternalAPI/>
///<SecurityNote>
/// Critical: calls InstanceDescriptor ctor which LinkDemands
/// PublicOK: can only make an InstanceDescriptor for RepeatBehavior, not an arbitrary class
///</SecurityNote>
[SecurityCritical]
public override object ConvertTo(
ITypeDescriptorContext context,
CultureInfo cultureInfo,
object value,
Type destinationType)
{
if ( value is RepeatBehavior
&& destinationType != null)
{
RepeatBehavior repeatBehavior = (RepeatBehavior)value;
if (destinationType == typeof(InstanceDescriptor))
{
MemberInfo mi;
if (repeatBehavior == RepeatBehavior.Forever)
{
mi = typeof(RepeatBehavior).GetProperty("Forever");
return new InstanceDescriptor(mi, null);
}
else if (repeatBehavior.HasCount)
{
mi = typeof(RepeatBehavior).GetConstructor(new Type[] { typeof(double) });
return new InstanceDescriptor(mi, new object[] { repeatBehavior.Count });
}
else if (repeatBehavior.HasDuration)
{
mi = typeof(RepeatBehavior).GetConstructor(new Type[] { typeof(TimeSpan) });
return new InstanceDescriptor(mi, new object[] { repeatBehavior.Duration });
}
else
{
Debug.Fail("Unknown type of RepeatBehavior passed to RepeatBehaviorConverter.");
}
}
else if (destinationType == typeof(string))
{
return repeatBehavior.InternalToString(null, cultureInfo);
}
}
// We can't do the conversion, let the base class raise the
// appropriate exception.
return base.ConvertTo(context, cultureInfo, value, destinationType);
}
}
}
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