Discussion :

[escafr]

Bonjour,

j'ai trois classes comme celles-ci:

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// Objet business
    public class Customer
    {
        public String firstName {get; set;}
        public String lastName {get; set;}
        public int age {get; set;}
        public String sens { get; set; }
    }

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// Classe abstraite generique me permettant de factoriser le code pour implementer les interfaces IDataErrorInfo et INotifyPropertyChanged 
public abstract class GenericControler<T> : IDataErrorInfo, INotifyPropertyChanged where T : new()
    {
(...) // methodes pour IDataErrorInfo et INotifyPropertyChanged 
#region Generic Controler
        protected T baseObject {get; set;}
 
        public GenericControler()
        {
            baseObject = new T();
        }
 
        public abstract string validate(string propertyName);
 
        #endregion
}

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// La classe controler concrete
public class CustomerControler : GenericControler<Customer>
    {
       public String FirstName
        {
            get { return baseObject.firstName; }
            set {
                baseObject.firstName = value;
                this.OnPropertyChanged(new PropertyChangedEventArgs("First Name"));
            }
        }
 
        public String LastName
        {
            get { return baseObject.lastName; }
            set {
                baseObject.lastName = value;
                this.OnPropertyChanged(new PropertyChangedEventArgs("Last Name"));
             }
        }
 
        public int Age
        {
            get { return baseObject.age; }
            set { baseObject.age = value;
                this.OnPropertyChanged(new PropertyChangedEventArgs("Age"));           
            }
        }
 
        public String Sens
        {
            get { return baseObject.sens; }
            set { baseObject.sens = value;
                this.OnPropertyChanged(new PropertyChangedEventArgs("Sens"));
            }
        }
(...)

et je voudrais arriver à ça:

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public class CustomerControler : GenericControler<Customer>
    {
       [objectReference(baseObject.firstName, "FirstName")]
       public String FirstName {get; set;}
 
        [objectReference(baseObject.lastName, "LastName")]
        public String LastName {get; set;}
 
       [objectReference(baseObject.age, "Age")]
        public int Age {get; set;}
 
       [objectReference(baseObject.sens, "Sens")]
        public String Sens {get; set;}
        }

L'idée étant que mon attribut m'évite d'écrire pour chaque Property

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 set { baseObject.attribut = value;
                this.OnPropertyChanged(new PropertyChangedEventArgs("Attribut"));           
            }

Est-ce possible? Si oui comment?

Je suis preneur de tout autre moyen de m'eviter à écrire le dernier bout de code pour chacun des attributs de ma classe business dans la classe controler representant ma classe business

C'est exactement ce qu'explique databinding avancé sauf que je comprends rien au tuto..
donc si qqun pouvait juste me montrer au moins une piste du bout de code necessaire, ce serait cool

[Skyounet]

Nop j'ai jamais rien vu de tel même si j'avoue que ce serait super pratique.

C'est à toi de déclencher l'évènement quand ta prop est modifiée.

En général on passe plutôt par une méthode

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private void NotifyPropertyChanged(string propertyName)
{
   if(PropertyChanged != null) PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}

[escafr]

pourtant dans le lien en exemple, il semble utilisé RealProxy pour faire ce genre de chose. mais qd je regarde le code, ca ressemble tellement à une usine à gaz que ca me fait un peu peur..

[Guulh]

Le fait de devoir filer le nom de la propriété sous forme de chaîne de caractère est quelque chose qui turlupine les codeurs C# depuis des lustres
J'étais tombé sur des articles comme celui-ci : http://davybrion.com/blog/2009/08/re...opertychanged/ qui utilisent les Expression<T> dans une classe de base, et dont les classes filles peuvent avoir :

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public string MyString
        {
            get
            {
                return myString;
            }
            set
            {
                myString = value;
                NotifyPropertyChanged(t => t.MyString);
            }
        }

C'est là qu'on voit que les macros du style __LINE__ ou __FUNCTION__ de C++ manquent à C#

[zoubidaman]

On peut également faire ça avec PostSharp apparemment

[escafr]

Merci de m'avoir orienté vers PostSharp

En m inspirant très très largement de ce post sur le forum de PostSharp

Ca donne ceci:
Pour créer l'attribut NotifyPropertyChanged

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#region Released to Public Domain by Gael Fraiteur
/*----------------------------------------------------------------------------*
 *   This file is part of samples of PostSharp.                                *
 *                                                                             *
 *   This sample is free software: you have an unlimited right to              *
 *   redistribute it and/or modify it.                                         *
 *                                                                             *
 *   This sample is distributed in the hope that it will be useful,            *
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of            *
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.                      *
 *                                                                             *
 *----------------------------------------------------------------------------*/
#endregion
 
using System;
using System.ComponentModel;
using System.Reflection;
using PostSharp.Extensibility;
using PostSharp.Laos;
 
namespace PostSharp.Samples.Binding
{
    /// <summary>
    /// Custom attribute that, when applied on a type (designated <i>target type</i>), implements the interface
    /// <see cref="INotifyPropertyChanged"/> and raises the <see cref="INotifyPropertyChanged.PropertyChanged"/>
    /// event when any property of the target type is modified.
    /// </summary>
    /// <remarks>
    /// Event raising is implemented by appending logic to the <b>set</b> accessor of properties. The 
    /// <see cref="INotifyPropertyChanged.PropertyChanged"/> is raised only when accessors successfully complete.
    /// </remarks>
    [MulticastAttributeUsage( MulticastTargets.Class | MulticastTargets.Struct )]
    [Serializable]
    public sealed class NotifyPropertyChangedAttribute : CompoundAspect
    {
        [NonSerialized] private int aspectPriority = 0;
 
        /// <summary>
        /// Method called at compile time to get individual aspects required by the current compound
        /// aspect.
        /// </summary>
        /// <param name="targetElement">Metadata element (<see cref="Type"/> in our case) to which
        /// the current custom attribute instance is applied.</param>
        /// <param name="collection">Collection of aspects to which individual aspects should be
        /// added.</param>
        public override void ProvideAspects( object targetElement, LaosReflectionAspectCollection collection )
        {
            // Get the target type.
            Type targetType = (Type) targetElement;
 
            // On the type, add a Composition aspect to implement the INotifyPropertyChanged interface.
            collection.AddAspect( targetType, new AddNotifyPropertyChangedInterfaceSubAspect() );
 
            // Add a OnMethodBoundaryAspect on each writable non-static property.
            foreach ( PropertyInfo property in targetType.UnderlyingSystemType.GetProperties() )
            {
                if ( property.DeclaringType == targetType && property.CanWrite )
                {
                    MethodInfo method = property.GetSetMethod();
 
                    if ( !method.IsStatic )
                    {
                        collection.AddAspect( method, new OnPropertySetSubAspect( property.Name, this ) );
                    }
                }
            }
        }
 
        /// <summary>
        /// Gets or sets the priority of the property-level aspect.
        /// </summary>
        /// <remarks>
        /// Give a large number to have the event raisen after any other
        /// on-success aspect on the properties of this type. The default value
        /// is 0.
        /// </remarks>
        public int AspectPriority { get { return aspectPriority; } set { aspectPriority = value; } }
 
 
        /// <summary>
        /// Implementation of <see cref="OnMethodBoundaryAspect"/> that raises the 
        /// <see cref="INotifyPropertyChanged.PropertyChanged"/> event when a property set
        /// accessor completes successfully.
        /// </summary>
        [Serializable]
        internal class OnPropertySetSubAspect : OnMethodBoundaryAspect
        {
            private readonly string propertyName;
 
            /// <summary>
            /// Initializes a new <see cref="OnPropertySetSubAspect"/>.
            /// </summary>
            /// <param name="propertyName">Name of the property to which this set accessor belong.</param>
            /// <param name="parent">Parent <see cref="NotifyPropertyChangedAttribute"/>.</param>
            public OnPropertySetSubAspect( string propertyName, NotifyPropertyChangedAttribute parent )
            {
                this.AspectPriority = parent.AspectPriority;
                this.propertyName = propertyName;
            }
 
            /// <summary>
            /// Executed when the set accessor successfully completes. Raises the 
            /// <see cref="INotifyPropertyChanged.PropertyChanged"/> event.
            /// </summary>
            /// <param name="eventArgs">Event arguments with information about the 
            /// current execution context.</param>
            public override void OnSuccess( MethodExecutionEventArgs eventArgs )
            {
                // Get the implementation of INotifyPropertyChanged. We have access to it through the IComposed interface,
                // which is implemented at compile time.
                NotifyPropertyChangedImplementation implementation =
                    (NotifyPropertyChangedImplementation)
                    ( (IComposed<INotifyPropertyChanged>) eventArgs.Instance ).GetImplementation(
                        eventArgs.InstanceCredentials );
 
                // Raises the PropertyChanged event.
                implementation.OnPropertyChanged( this.propertyName );
            }
        }
 
        /// <summary>
        /// Implementation of <see cref="CompositionAspect"/> that adds the <see cref="INotifyPropertyChanged"/>
        /// interface to the type to which it is applied.
        /// </summary>
        [Serializable]
        internal class AddNotifyPropertyChangedInterfaceSubAspect : CompositionAspect
        {
            /// <summary>
            /// Called at runtime, creates the implementation of the <see cref="INotifyPropertyChanged"/> interface.
            /// </summary>
            /// <param name="eventArgs">Execution context.</param>
            /// <returns>A new instance of <see cref="NotifyPropertyChangedImplementation"/>, which implements
            /// <see cref="INotifyPropertyChanged"/>.</returns>
            public override object CreateImplementationObject( InstanceBoundLaosEventArgs eventArgs )
            {
                return new NotifyPropertyChangedImplementation( eventArgs.Instance );
            }
 
            /// <summary>
            /// Called at compile-time, gets the interface that should be publicly exposed.
            /// </summary>
            /// <param name="containerType">Type on which the interface will be implemented.</param>
            /// <returns></returns>
            public override Type GetPublicInterface( Type containerType )
            {
                return typeof(INotifyPropertyChanged);
            }
 
            public override Type[] GetProtectedInterfaces(Type containerType)
            {
                return new Type[] {typeof(IFirePropertyChanged)};
            }
 
            /// <summary>
            /// Gets weaving options.
            /// </summary>
            /// <returns>Weaving options specifying that the implementation accessor interface (<see cref="IComposed{T}"/>)
            /// should be exposed, and that the implementation of interfaces should be silently ignored if they are
            /// already implemented in the parent types.</returns>
            public override CompositionAspectOptions GetOptions()
            {
                return
                    CompositionAspectOptions.GenerateImplementationAccessor |
                    CompositionAspectOptions.IgnoreIfAlreadyImplemented;
            }
        }
 
        /// <summary>
        /// Implementation of the <see cref="INotifyPropertyChanged"/> interface.
        /// </summary>
        internal class NotifyPropertyChangedImplementation : INotifyPropertyChanged, IFirePropertyChanged
        {
            // Instance that exposes the current implementation.
            private readonly object instance;
 
            /// <summary>
            /// Initializes a new <see cref="NotifyPropertyChangedImplementation"/> instance.
            /// </summary>
            /// <param name="instance">Instance that exposes the current implementation.</param>
            public NotifyPropertyChangedImplementation( object instance )
            {
                this.instance = instance;
            }
 
            /// <summary>
            /// Event raised when a property is changed on the instance that
            /// exposes the current implementation.
            /// </summary>
            public event PropertyChangedEventHandler PropertyChanged;
 
            /// <summary>
            /// Raises the <see cref="PropertyChanged"/> event. Called by the
            /// property-level aspect (<see cref="AddNotifyPropertyChangedInterfaceSubAspect"/>)
            /// at the end of property set accessors.
            /// </summary>
            /// <param name="propertyName">Name of the changed property.</param>
            public void OnPropertyChanged( string propertyName )
            {
                if ( this.PropertyChanged != null )
                {
                    this.PropertyChanged( this.instance, new PropertyChangedEventArgs( propertyName ) );
                }
            }
        }
    }
}

mon controleur generique:

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using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.ComponentModel;
 
namespace WpfApplication_TestValidation
{
    public abstract class GenericControler<T> : IDataErrorInfo, INotifyPropertyChanged where T : new()
    {
        #region INotifyPropertyChanged Members
 
        public event PropertyChangedEventHandler PropertyChanged;
 
        protected virtual void OnPropertyChanged(string e)
        {
            PropertyChangedEventHandler handler = PropertyChanged;
 
            if (handler != null)
            {
                handler(this, new PropertyChangedEventArgs(e));
            }
        }
        #endregion
 
        #region IDataErrorInfo Members
 
        public string Error
        {
            get { return this[null]; }
        }
 
        public string this[string propertyName]
        {
            get
            {
                propertyName = propertyName ?? string.Empty;
                return validate(propertyName);
            }
        }
        #endregion
 
        #region Generic Controler
        protected T baseObject {get; set;}
 
        public GenericControler()
        {
            baseObject = new T();
        }
 
        public abstract string validate(string propertyName);
 
        #endregion
    }
 
}

l'objet business et son controler windows1.xaml.cs

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using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
using System.ComponentModel;
 
namespace WpfApplication_TestValidation
{
    /// <summary>
    /// Interaction logic for Window1.xaml
    /// </summary>
    public partial class Window1 : Window
    {
        CustomerControler baseObject;
 
        public Window1()
        {
            InitializeComponent();
            var lSens = new List<string> { "BUY", "SELL" };
            sens.ItemsSource = lSens;
            sens.SelectedIndex = 0;
            DataContext = baseObject = new CustomerControler();
        }
 
        private void Button_Click(object sender, RoutedEventArgs e)
        {
            String result = baseObject.validate("");
            if (result.Length != 0)
                MessageBox.Show(result);
            else
                MessageBox.Show("Je valide!");
        }
    }
 
    public class Customer
    {
        public String firstName {get; set;}
        public String lastName {get; set;}
        public int age {get; set;}
        public String sens { get; set; }
    }
 
 
    [NotifyPropertyChanged(OnPropertyChanged = "OnPropertyChanged")]
    public class CustomerControler : GenericControler<Customer>
    {      
       public String FirstName
        {
            get { return baseObject.firstName; }
            set { baseObject.firstName = value; }
        }
 
        public String LastName
        {
            get { return baseObject.lastName; }
            set { baseObject.lastName = value; }
        }
 
        public int Age
        {
            get { return baseObject.age; }
            set { baseObject.age = value; }
        }
 
        public String Sens
        {
            get { return baseObject.sens; }
            set { baseObject.sens = value; }
        }
 
        public override string validate(string propertyName)
        {
            string result = String.Empty;
            if (propertyName == string.Empty || propertyName == "FirstName")
            {
                if (string.IsNullOrEmpty(this.FirstName))
                {
                    result += "First Name is mandatory." + Environment.NewLine;
                }
            }
 
            if (propertyName == string.Empty || propertyName == "LastName")
            {
                if (string.IsNullOrEmpty(this.LastName) || this.LastName.Length > 30)
                {
                    result += "Last Name is mandatory and must be less than 30 letters."
                        + Environment.NewLine;
                }
            }
 
            if (propertyName == string.Empty || propertyName == "Age")
            {
                if (string.IsNullOrEmpty(this.Age.ToString()))
                {
                    result += "Age is mandatory." + Environment.NewLine;
                }
                if (this.Age < 10)
                    result += "Too young!" + Environment.NewLine;
            }
 
            if (propertyName == string.Empty || propertyName == "Sens")
            {
                if (string.IsNullOrEmpty(this.Sens))
                {
                    result += "Sens is mandatory." + Environment.NewLine;
                }               
            }
            return result.TrimEnd();
        }
 
    }
 
}

Merci à tous.
Ca marche nickel pour faire du binding avec WPF

app.xaml

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<Application x:Class="WpfApplication_TestValidation.App"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:igEditors="http://infragistics.com/Editors"
    StartupUri="Window1.xaml">
    <Application.Resources>
         <Style x:Key="validationStyle" TargetType="{x:Type Control}">
            <Setter Property="Validation.ErrorTemplate">
                <Setter.Value>
                    <ControlTemplate>
                        <DockPanel LastChildFill="True">
                            <Border BorderBrush="Red" BorderThickness="1">
                                <AdornedElementPlaceholder />
                            </Border>
                        </DockPanel>
                    </ControlTemplate>
                </Setter.Value>
            </Setter>
            <Style.Triggers>
                <Trigger Property="Validation.HasError" Value="true">
                    <Setter Property="ToolTip"
                Value="{Binding RelativeSource={RelativeSource Self}, 
                       Path=(Validation.Errors)[0].ErrorContent}"/>
                </Trigger>
            </Style.Triggers>
        </Style>
        <Style TargetType="{x:Type igEditors:XamComboEditor}" BasedOn="{StaticResource validationStyle}" />  
        <Style TargetType="{x:Type igEditors:XamMaskedEditor}" BasedOn="{StaticResource validationStyle}" />        
    </Application.Resources>
</Application>

Windows1.xaml

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<Window x:Class="WpfApplication_TestValidation.Window1"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:igEditors="http://infragistics.com/Editors"
    xmlns:sys="clr-namespace:System;assembly=mscorlib"
    xmlns:local="clr-namespace:WpfApplication_TestValidation"
    Title="Window1" Height="300" Width="300">
    <Grid>
        <local:ErrorProvider>
            <WrapPanel>
                <Label>First Name</Label>
                <igEditors:XamMaskedEditor Text="{Binding Path=FirstName, UpdateSourceTrigger=PropertyChanged}" ValueType="{x:Type sys:String}" Width="90"/>
                <Label>Last Name</Label>
                <igEditors:XamMaskedEditor Text="{Binding Path=LastName, UpdateSourceTrigger=PropertyChanged}" ValueType="{x:Type sys:String}" Width="90"/>                   
                <Label>Age</Label>
                <igEditors:XamMaskedEditor Text="{Binding Path=Age, UpdateSourceTrigger=PropertyChanged}" ValueType="{x:Type sys:Int32}" Width="90"/>
                <Label >Sens :</Label>
                <igEditors:XamComboEditor  Name="sens" Text="{Binding Path=Sens, UpdateSourceTrigger=PropertyChanged}" ValueType="{x:Type sys:String}"  Width="90"/>
                <Button Click="Button_Click" >Validate</Button>
            </WrapPanel>
        </local:ErrorProvider>
    </Grid>
</Window>

errorprovider.cs trouvé je sais plus trop où...

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using System;
using System.Collections.Generic;
using System.Text;
using System.Windows.Controls;
using System.Windows;
using System.ComponentModel;
using System.Windows.Data;
using System.Reflection;
 
namespace WpfApplication_TestValidation
{
    public class ErrorProvider : Decorator
    {
        private delegate void FoundBindingCallbackDelegate(FrameworkElement element, Binding binding, DependencyProperty dp);
        private FrameworkElement _firstInvalidElement;
        private Dictionary<DependencyObject, Style> _backupStyles = new Dictionary<DependencyObject, Style>();
 
        /// <summary>
        /// Constructor.
        /// </summary>
        public ErrorProvider()
        {
            this.DataContextChanged += new DependencyPropertyChangedEventHandler(ErrorProvider_DataContextChanged);
            this.Loaded += new RoutedEventHandler(ErrorProvider_Loaded);
        }
 
        /// <summary>
        /// Called when this component is loaded. We have a call to Validate here that way errors appear from the very 
        /// moment the page or form is visible.
        /// </summary>
        private void ErrorProvider_Loaded(object sender, RoutedEventArgs e)
        {
            Validate();
        }
 
        /// <summary>
        /// Called when our DataContext changes.
        /// </summary>
        private void ErrorProvider_DataContextChanged(object sender, DependencyPropertyChangedEventArgs e)
        {
            if (e.OldValue != null && e.OldValue is INotifyPropertyChanged)
            {
                ((INotifyPropertyChanged)e.NewValue).PropertyChanged -= new PropertyChangedEventHandler(DataContext_PropertyChanged);
            }
 
            if (e.NewValue != null && e.NewValue is INotifyPropertyChanged)
            {
                ((INotifyPropertyChanged)e.NewValue).PropertyChanged += new PropertyChangedEventHandler(DataContext_PropertyChanged);
            }
 
            Validate();
        }
 
        /// <summary>
        /// Validates all properties on the current data source.
        /// </summary>
        /// <returns>True if there are no errors displayed, otherwise false.</returns>
        /// <remarks>
        /// Note that only errors on properties that are displayed are included. Other errors, such as errors for properties that are not displayed, 
        /// will not be validated by this method.
        /// </remarks>
        public bool Validate()
        {
            bool isValid = true;
            _firstInvalidElement = null;
 
            if (this.DataContext is IDataErrorInfo)
            {
                List<Binding> allKnownBindings = ClearInternal();
 
                // Now show all errors
                foreach (Binding knownBinding in allKnownBindings)
                {
                    string errorMessage = ((IDataErrorInfo)this.DataContext)[knownBinding.Path.Path];
                    if (errorMessage != null && errorMessage.Length > 0)
                    {
                        isValid = false;
 
                        // Display the error on any elements bound to the property
                        FindBindingsRecursively(
                        this.Parent,
                        delegate(FrameworkElement element, Binding binding, DependencyProperty dp)
                        {
                            if (knownBinding.Path.Path == binding.Path.Path)
                            {
 
                                BindingExpression expression = element.GetBindingExpression(dp);
                                ValidationError error = new ValidationError(new ExceptionValidationRule(), expression, errorMessage, null);
                                System.Windows.Controls.Validation.MarkInvalid(expression, error);
 
                                if (_firstInvalidElement == null)
                                {
                                    _firstInvalidElement = element;
                                }
                                return;
 
                            }
                        });
                    }
                }
            }
            return isValid;
        }
 
        /// <summary>
        /// Returns the first element that this error provider has labelled as invalid. This method 
        /// is useful to set the users focus on the first visible error field on a page.
        /// </summary>
        /// <returns></returns>
        public FrameworkElement GetFirstInvalidElement()
        {
            return _firstInvalidElement;
        }
 
        /// <summary>
        /// Clears any error messages.
        /// </summary>
        public void Clear()
        {
            ClearInternal();
        }
 
        /// <summary>
        /// Clears any error messages and returns a list of all bindings on the current form/page. This is simply so 
        /// it can be reused by the Validate method.
        /// </summary>
        /// <returns>A list of all known bindings.</returns>
        private List<Binding> ClearInternal()
        {
            // Clear all errors
            List<Binding> bindings = new List<Binding>();
            FindBindingsRecursively(
                    this.Parent,
                    delegate(FrameworkElement element, Binding binding, DependencyProperty dp)
                    {
                        // Remember this bound element. We'll use this to display error messages for each property.
                        bindings.Add(binding);
                    });
            return bindings;
        }
 
        /// <summary>
        /// Called when the PropertyChanged event is raised from the object we are bound to - that is, our data context.
        /// </summary>
        private void DataContext_PropertyChanged(object sender, PropertyChangedEventArgs e)
        {
            if (e.PropertyName == "IsValid")
            {
                return;
            }
            Validate();
        }
 
        /// <summary>
        /// Recursively goes through the control tree, looking for bindings on the current data context.
        /// </summary>
        /// <param name="element">The root element to start searching at.</param>
        /// <param name="callbackDelegate">A delegate called when a binding if found.</param>
        private void FindBindingsRecursively(DependencyObject element, FoundBindingCallbackDelegate callbackDelegate)
        {
 
            // See if we should display the errors on this element
            MemberInfo[] members = element.GetType().GetMembers(BindingFlags.Static | 
                    BindingFlags.Public |
                    BindingFlags.FlattenHierarchy);
 
            foreach (MemberInfo member in members)
            {
                DependencyProperty dp = null;
 
                // Check to see if the field or property we were given is a dependency property
                if (member.MemberType == MemberTypes.Field)
                {
                    FieldInfo field = (FieldInfo)member;
                    if (typeof(DependencyProperty).IsAssignableFrom(field.FieldType))
                    {
                        dp = (DependencyProperty)field.GetValue(element);
                    }
                }
                else if (member.MemberType == MemberTypes.Property)
                {
                    PropertyInfo prop = (PropertyInfo)member;
                    if (typeof(DependencyProperty).IsAssignableFrom(prop.PropertyType))
                    {
                        dp = (DependencyProperty)prop.GetValue(element, null);
                    }
                }
 
                if (dp != null)
                {
                    // Awesome, we have a dependency property. does it have a binding? If yes, is it bound to the property we're interested in?
                    Binding bb = BindingOperations.GetBinding(element, dp);
                    if (bb != null)
                    {
                        // This element has a DependencyProperty that we know of that is bound to the property we're interested in. 
                        // Now we just tell the callback and the caller will handle it.
                        if (element is FrameworkElement)
                        {
                            if (((FrameworkElement)element).DataContext == this.DataContext)
                            {
                                callbackDelegate((FrameworkElement)element, bb, dp);
                            }
                        }
                    }
                }
            }
 
            // Now, recurse through any child elements
            if (element is FrameworkElement || element is FrameworkContentElement)
            {
                foreach (object childElement in LogicalTreeHelper.GetChildren(element))
                {
                    if (childElement is DependencyObject)
                    {
                        FindBindingsRecursively((DependencyObject)childElement, callbackDelegate);
                    }
                }
            }
        }
    }
}

J'utilise la lib graphique infragistics mais ca marche pareil avc les TextBox wpf de base.