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//---------------------------------------------------------------------------
//
// Copyright (C) Microsoft Corporation. All rights reserved.
//
// File: ThicknessConverter.cs
//
// Description: Contains the ThicknessConverter: TypeConverter for the Thicknessclass.
//
// History:
// 07/09/2003 : greglett - Added to WCP branch (was contained in BoxUnitThickness.cs in old Avalon)
//
//---------------------------------------------------------------------------
using System;
using System.ComponentModel;
using System.ComponentModel.Design.Serialization;
using System.Globalization;
using System.Reflection;
using System.Text;
using System.Windows;
using System.Security;
using MS.Internal;
using MS.Utility;
#pragma warning disable 1634, 1691 // suppressing PreSharp warnings
namespace System.Windows
{
/// <summary>
/// ThicknessConverter - Converter class for converting instances of other types to and from Thickness instances.
/// </summary>
public class ThicknessConverter : TypeConverter
{
#region Public Methods
/// <summary>
/// CanConvertFrom - Returns whether or not this class can convert from a given type.
/// </summary>
/// <returns>
/// bool - True if thie converter can convert from the provided type, false if not.
/// </returns>
/// <param name="typeDescriptorContext"> The ITypeDescriptorContext for this call. </param>
/// <param name="sourceType"> The Type being queried for support. </param>
public override bool CanConvertFrom(ITypeDescriptorContext typeDescriptorContext, Type sourceType)
{
// We can only handle strings, integral and floating types
TypeCode tc = Type.GetTypeCode(sourceType);
switch (tc)
{
case TypeCode.String:
case TypeCode.Decimal:
case TypeCode.Single:
case TypeCode.Double:
case TypeCode.Int16:
case TypeCode.Int32:
case TypeCode.Int64:
case TypeCode.UInt16:
case TypeCode.UInt32:
case TypeCode.UInt64:
return true;
default:
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 Thickness from the given object
/// </summary>
/// <returns>
/// The Thickness 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 example object is not null and is not a valid type
/// which can be converted to a Thickness.
/// </exception>
/// <param name="typeDescriptorContext"> The ITypeDescriptorContext for this call. </param>
/// <param name="cultureInfo"> The CultureInfo which is respected when converting. </param>
/// <param name="source"> The object to convert to a Thickness. </param>
public override object ConvertFrom(ITypeDescriptorContext typeDescriptorContext, CultureInfo cultureInfo, object source)
{
if (source != null)
{
if (source is string) { return FromString((string)source, cultureInfo); }
else if (source is double) { return new Thickness((double)source); }
else { return new Thickness(Convert.ToDouble(source, cultureInfo)); }
}
throw GetConvertFromException(source);
}
/// <summary>
/// ConvertTo - Attempt to convert a Thickness to the given type
/// </summary>
/// <returns>
/// The object which was constructoed.
/// </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 and is not a Thickness,
/// 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 Thickness to convert. </param>
/// <param name="destinationType">The type to which to convert the Thickness instance. </param>
///<SecurityNote>
/// Critical: calls InstanceDescriptor ctor which LinkDemands
/// PublicOK: can only make an InstanceDescriptor for Thickness, not an arbitrary class
///</SecurityNote>
[SecurityCritical]
public override object ConvertTo(ITypeDescriptorContext typeDescriptorContext, CultureInfo cultureInfo, object value, Type destinationType)
{
if (null == value)
{
throw new ArgumentNullException("value");
}
if (null == destinationType)
{
throw new ArgumentNullException("destinationType");
}
if (!(value is Thickness))
{
#pragma warning suppress 6506 // value is obviously not null
throw new ArgumentException(SR.Get(SRID.UnexpectedParameterType, value.GetType(), typeof(Thickness)), "value");
}
Thickness th = (Thickness)value;
if (destinationType == typeof(string)) { return ToString(th, cultureInfo); }
if (destinationType == typeof(InstanceDescriptor))
{
ConstructorInfo ci = typeof(Thickness).GetConstructor(new Type[] { typeof(double), typeof(double), typeof(double), typeof(double) });
return new InstanceDescriptor(ci, new object[] { th.Left, th.Top, th.Right, th.Bottom });
}
throw new ArgumentException(SR.Get(SRID.CannotConvertType, typeof(Thickness), destinationType.FullName));
}
#endregion Public Methods
//-------------------------------------------------------------------
//
// Internal Methods
//
//-------------------------------------------------------------------
#region Internal Methods
static internal string ToString(Thickness th, CultureInfo cultureInfo)
{
char listSeparator = TokenizerHelper.GetNumericListSeparator(cultureInfo);
// Initial capacity [64] is an estimate based on a sum of:
// 48 = 4x double (twelve digits is generous for the range of values likely)
// 8 = 4x Unit Type string (approx two characters)
// 4 = 4x separator characters
StringBuilder sb = new StringBuilder(64);
sb.Append(LengthConverter.ToString(th.Left, cultureInfo));
sb.Append(listSeparator);
sb.Append(LengthConverter.ToString(th.Top, cultureInfo));
sb.Append(listSeparator);
sb.Append(LengthConverter.ToString(th.Right, cultureInfo));
sb.Append(listSeparator);
sb.Append(LengthConverter.ToString(th.Bottom, cultureInfo));
return sb.ToString();
}
static internal Thickness FromString(string s, CultureInfo cultureInfo)
{
TokenizerHelper th = new TokenizerHelper(s, cultureInfo);
double[] lengths = new double[4];
int i = 0;
// Peel off each double in the delimited list.
while (th.NextToken())
{
if (i >= 4)
{
i = 5; // Set i to a bad value.
break;
}
lengths[i] = LengthConverter.FromString(th.GetCurrentToken(), cultureInfo);
i++;
}
// We have a reasonable interpreation for one value (all four edges), two values (horizontal, vertical),
// and four values (left, top, right, bottom).
switch (i)
{
case 1:
return new Thickness(lengths[0]);
case 2:
return new Thickness(lengths[0], lengths[1], lengths[0], lengths[1]);
case 4:
return new Thickness(lengths[0], lengths[1], lengths[2], lengths[3]);
}
throw new FormatException(SR.Get(SRID.InvalidStringThickness, s));
}
#endregion
}
}
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