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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.ComponentModel;
using System.Globalization;
using System.Reflection;
using System.Windows.Media; // TypeConverterHelper, UriHolder
using MS.Internal.PresentationCore;
using MS.Internal; // BindUriHelper
namespace System.Windows.Input
{
/// <summary>
/// TypeConverter to convert CursorType to/from other types.
/// Currently To/From string is only supported.
/// </summary>
public class CursorConverter : TypeConverter
{
/// <summary>
/// TypeConverter method override.
/// </summary>
/// <param name="context">ITypeDescriptorContext</param>
/// <param name="sourceType">Type to convert from</param>
/// <returns>true if conversion is possible</returns>
public override bool CanConvertFrom(ITypeDescriptorContext context, Type sourceType)
{
if(sourceType == typeof(string))
{
return true;
}
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>
public override bool CanConvertTo(ITypeDescriptorContext context, Type destinationType)
{
if (destinationType == typeof(string))
{
return true;
}
return false;
}
/// <summary>
/// StandardValuesCollection method override
/// </summary>
/// <param name="context">ITypeDescriptorContext</param>
/// <returns>TypeConverter.StandardValuesCollection</returns>
public override TypeConverter.StandardValuesCollection GetStandardValues(ITypeDescriptorContext context)
{
if(_standardValues is null)
{
PropertyInfo[] properties = typeof(Cursors).GetProperties(BindingFlags.Public | BindingFlags.Static);
object[] values = new object[properties.Length]; //Could use Cursor but its wrapped in ICollection anyways
for (int i = 0; i < properties.Length; i++)
{
PropertyInfo info = properties[i];
values[i] = info.GetValue(null, null);
}
_standardValues = new TypeConverter.StandardValuesCollection(values);
}
return _standardValues;
}
/// <summary>
/// Returns whether this object supports a standard set of values that can be
/// picked from a list, using the specified context.
/// </summary>
/// <param name="context">An ITypeDescriptorContext that provides a format context.</param>
/// <returns>
/// true if GetStandardValues should be called to find a common set
/// of values the object supports; otherwise, false.
/// </returns>
public override bool GetStandardValuesSupported(ITypeDescriptorContext context)
{
return true;
}
/// <summary>
/// TypeConverter method implementation.
/// </summary>
/// <param name="context">ITypeDescriptorContext</param>
/// <param name="culture">current culture (see CLR specs)</param>
/// <param name="value">value to convert from</param>
/// <returns>value that is result of conversion</returns>
public override object ConvertFrom(ITypeDescriptorContext context, CultureInfo culture, object value)
{
if (value is string)
{
string text = ((string)value).Trim();
if (text != String.Empty)
{
if (text.LastIndexOf('.') == -1)
{
CursorType ct = Enum.Parse<CursorType>(text);
switch (ct)
{
case CursorType.Arrow:
return Cursors.Arrow;
case CursorType.AppStarting:
return Cursors.AppStarting;
case CursorType.Cross:
return Cursors.Cross;
case CursorType.Help:
return Cursors.Help;
case CursorType.IBeam:
return Cursors.IBeam;
case CursorType.SizeAll:
return Cursors.SizeAll;
case CursorType.SizeNESW:
return Cursors.SizeNESW;
case CursorType.SizeNS:
return Cursors.SizeNS;
case CursorType.SizeNWSE:
return Cursors.SizeNWSE;
case CursorType.SizeWE:
return Cursors.SizeWE;
case CursorType.UpArrow:
return Cursors.UpArrow;
case CursorType.Wait:
return Cursors.Wait;
case CursorType.Hand:
return Cursors.Hand;
case CursorType.No:
return Cursors.No;
case CursorType.None:
return Cursors.None;
case CursorType.Pen:
return Cursors.Pen;
case CursorType.ScrollNS:
return Cursors.ScrollNS;
case CursorType.ScrollWE:
return Cursors.ScrollWE;
case CursorType.ScrollAll:
return Cursors.ScrollAll;
case CursorType.ScrollN:
return Cursors.ScrollN;
case CursorType.ScrollS:
return Cursors.ScrollS;
case CursorType.ScrollW:
return Cursors.ScrollW;
case CursorType.ScrollE:
return Cursors.ScrollE;
case CursorType.ScrollNW:
return Cursors.ScrollNW;
case CursorType.ScrollNE:
return Cursors.ScrollNE;
case CursorType.ScrollSW:
return Cursors.ScrollSW;
case CursorType.ScrollSE:
return Cursors.ScrollSE;
case CursorType.ArrowCD:
return Cursors.ArrowCD;
}
}
else
{
if (text.EndsWith(".cur", StringComparison.OrdinalIgnoreCase) || text.EndsWith(".ani", StringComparison.OrdinalIgnoreCase))
{
UriHolder uriHolder = TypeConverterHelper.GetUriFromUriContext(context, text);
Uri finalUri = BindUriHelper.GetResolvedUri(uriHolder.BaseUri, uriHolder.OriginalUri);
if (finalUri.IsAbsoluteUri && finalUri.IsFile)
{
return new Cursor(finalUri.LocalPath);
}
else
{
System.Net.WebRequest request = WpfWebRequestHelper.CreateRequest(finalUri);
WpfWebRequestHelper.ConfigCachePolicy(request, false);
return new Cursor(WpfWebRequestHelper.GetResponseStream(request));
}
}
}
}
else
{
// An empty string means no cursor.
return null;
}
}
throw GetConvertFromException(value);
}
/// <summary>
/// TypeConverter method implementation.
/// </summary>
/// <param name="context">ITypeDescriptorContext</param>
/// <param name="culture">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>
public override object ConvertTo(ITypeDescriptorContext context, CultureInfo culture, object value, Type destinationType)
{
ArgumentNullException.ThrowIfNull(destinationType);
// If value is not a Cursor or null, it will throw GetConvertToException.
if (destinationType == typeof(string))
{
Cursor cursor = value as Cursor;
if (cursor != null)
{
return cursor.ToString();
}
else
{
return String.Empty;
}
}
throw GetConvertToException(value, destinationType);
}
/// <summary>
/// Cached value for GetStandardValues
/// </summary>
private TypeConverter.StandardValuesCollection _standardValues;
}
}
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