DPTypeDescriptorContext.cs source code in C# .NET

                        Code:
                         / DotNET / DotNET / 8.0 / untmp / WIN_WINDOWS / lh_tools_devdiv_wpf / Windows / wcp / Framework / System / Windows / Documents / DPTypeDescriptorContext.cs / 1 / DPTypeDescriptorContext.cs
                        
                        
                            //---------------------------------------------------------------------------- 
//
// File: TextRangeSerialization.cs
//
// Copyright (C) Microsoft Corporation.  All rights reserved. 
//
// Description: Set of static methods implementing text range serialization 
// 
//---------------------------------------------------------------------------
 
namespace System.Windows.Documents
{
    using MS.Internal;
    using System.Windows; 
    using System.Globalization;
    using System.Windows.Media; 
 
    /// 
    /// An object implementing ITypeDescriptorContext intended to be used in serialization 
    /// scenarios for checking whether a particular value can be converted to a string
    /// 
    internal class DPTypeDescriptorContext : System.ComponentModel.ITypeDescriptorContext
    { 
        //-----------------------------------------------------
        // 
        //  Constructors 
        //
        //----------------------------------------------------- 

        #region Constructors

        private DPTypeDescriptorContext(DependencyProperty property, object propertyValue) 
        {
            Invariant.Assert(property != null, "property == null"); 
            Invariant.Assert(propertyValue != null, "propertyValue == null"); 
            Invariant.Assert(property.IsValidValue(propertyValue), "propertyValue must be of suitable type for the given dependency property");
 
            _property = property;
            _propertyValue = propertyValue;
        }
 
        #endregion Constructors
 
        //------------------------------------------------------ 
        //
        //  Internal Methods 
        //
        //-----------------------------------------------------

        #region Internal Methods 

        // Returns non-null string if this value can be converted to a string, 
        // null otherwise. 
        internal static string GetStringValue(DependencyProperty property, object propertyValue)
        { 
            string stringValue = null;

            // Special cases working around incorrectly implemented type converters
            if (property == UIElement.BitmapEffectProperty) 
            {
                return null; // Always treat BitmapEffects as complex value 
            } 

            if (property == Inline.TextDecorationsProperty) 
            {
                stringValue = TextDecorationsFixup((TextDecorationCollection)propertyValue);
            }
            else if (typeof(CultureInfo).IsAssignableFrom(property.PropertyType)) //NumberSubstitution.CultureOverrideProperty 
            {
                stringValue = CultureInfoFixup(property, (CultureInfo)propertyValue); 
            } 

            if (stringValue == null) 
            {
                DPTypeDescriptorContext context = new DPTypeDescriptorContext(property, propertyValue);

                System.ComponentModel.TypeConverter typeConverter = System.ComponentModel.TypeDescriptor.GetConverter(property.PropertyType); 
                Invariant.Assert(typeConverter != null);
                if (typeConverter.CanConvertTo(context, typeof(string))) 
                { 
                    stringValue = (string)typeConverter.ConvertTo(
                        context, System.Globalization.CultureInfo.InvariantCulture, propertyValue, typeof(string)); 
                }
            }
            return stringValue;
        } 

        #endregion Internal Methods 
        #region Private Methods 
        private static string TextDecorationsFixup(TextDecorationCollection textDecorations)
        { 
            string stringValue = null;
            // Work around for incorrect serialization for TextDecorations property
            //
 
            // Special case for TextDecorations serialization
            if (TextDecorations.Underline.ValueEquals(textDecorations)) 
            { 
                stringValue = "Underline";
            } 
            else if (TextDecorations.Strikethrough.ValueEquals(textDecorations))
            {
                stringValue = "Strikethrough";
            } 
            else if (TextDecorations.OverLine.ValueEquals(textDecorations))
            { 
                stringValue = "OverLine"; 
            }
            else if (TextDecorations.Baseline.ValueEquals(textDecorations)) 
            {
                stringValue = "Baseline";
            }
            else if (textDecorations.Count == 0) 
            {
                stringValue = string.Empty; 
            
} 

            return stringValue; 

        }

        private static string CultureInfoFixup(DependencyProperty property, CultureInfo cultureInfo) 
        {
            string stringValue = null; 
 
            // Parser uses a specific type coverter for converting instances of other types to and from CultureInfo.
            // This class differs from System.ComponentModel.CultureInfoConverter, the default type converter 
            // for the CultureInfo class.
            // It uses a string representation based on the IetfLanguageTag property rather than the Name property
            // (i.e., RFC 3066 rather than RFC 1766).
            // In order to guarantee roundtripability of serialized xaml, textrange serialization needs to use 
            // this type coverter for CultureInfo types.
 
            DPTypeDescriptorContext context = new DPTypeDescriptorContext(property, cultureInfo); 
            System.ComponentModel.TypeConverter typeConverter = new CultureInfoIetfLanguageTagConverter();
 
            if (typeConverter.CanConvertTo(context, typeof(string)))
            {
                stringValue = (string)typeConverter.ConvertTo(
                    context, System.Globalization.CultureInfo.InvariantCulture, cultureInfo, typeof(string)); 
            }
            return stringValue; 
        } 
        #endregion  Private Methods
        //------------------------------------------------------ 
        //
        //  Interface ITypeDescriptorContext
        //
        //------------------------------------------------------ 

        #region ITypeDescriptorContext Members 
 
        System.ComponentModel.IContainer System.ComponentModel.ITypeDescriptorContext.Container
        { 
            get { return null; }
        }

        // Returns a value of a property - to be detected for convertability to string in a type converter 
        object System.ComponentModel.ITypeDescriptorContext.Instance
        { 
            get 
            {
                return _propertyValue; 
            }
        }

        void System.ComponentModel.ITypeDescriptorContext.OnComponentChanged() 
        {
        } 
 
        bool System.ComponentModel.ITypeDescriptorContext.OnComponentChanging()
        { 
            return false;
        }

        System.ComponentModel.PropertyDescriptor System.ComponentModel.ITypeDescriptorContext.PropertyDescriptor 
        {
            get { return null; } 
        } 

        #endregion 

        #region IServiceProvider Members

        object IServiceProvider.GetService(Type serviceType) 
        {
            return null; 
        } 

        #endregion 

        #region Private Fields

        private DependencyProperty _property; 
        private object _propertyValue;
 
        #endregion 
    }
} 

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
// Copyright (c) Microsoft Corporation. All rights reserved.
Link Menu

Network programming in C#, Network Programming in VB.NET, Network Programming in .NET
This book is available now!
Buy at Amazon US or
Buy at Amazon UK
DPTypeDescriptorContext.cs source code in C# .NET

Source code for the .NET framework in C#

Code:

Link Menu
