WPF: जब कोई प्रॉपर्टी बाइंडिंग का समर्थन नहीं करती है तो क्या करें

 using System; using System.Diagnostics; using System.Linq; using System.Linq.Expressions; using System.Reflection; using System.Windows; using System.Windows.Interactivity; using Expression = System.Linq.Expressions.Expression; namespace DependecyPropertyBehaviorNamesapce { public class DependecyPropertyBehavior : Behavior<DependencyObject> { private Delegate _handler; private EventInfo _eventInfo; private PropertyInfo _propertyInfo; public static readonly DependencyProperty BindingProperty = DependencyProperty.RegisterAttached( "Binding", typeof(object), typeof(DependecyPropertyBehavior), new FrameworkPropertyMetadata { BindsTwoWayByDefault = true } ); public object Binding { get { return GetValue(BindingProperty); } set { SetValue(BindingProperty, value); } } public string Property { get; set; } public string UpdateEvent { get; set; } protected override void OnAttached() { Type elementType = AssociatedObject.GetType(); _propertyInfo = elementType.GetProperty(Property, BindingFlags.Instance | BindingFlags.Public); _eventInfo = elementType.GetEvent(UpdateEvent); _handler = CreateDelegateForEvent(_eventInfo, EventFired); _eventInfo.AddEventHandler(AssociatedObject, _handler); } protected override void OnDetaching() { _eventInfo.RemoveEventHandler(AssociatedObject, _handler); } protected override void OnPropertyChanged(DependencyPropertyChangedEventArgs e) { if (e.Property.Name != "Binding") return; object oldValue = _propertyInfo.GetValue(AssociatedObject, null); if (oldValue.Equals(e.NewValue)) return; if (_propertyInfo.CanWrite) _propertyInfo.SetValue(AssociatedObject, e.NewValue, null); base.OnPropertyChanged(e); } private static Delegate CreateDelegateForEvent(EventInfo eventInfo, Action action) { ParameterExpression[] parameters = eventInfo .EventHandlerType .GetMethod("Invoke") .GetParameters() .Select(parameter => Expression.Parameter(parameter.ParameterType)) .ToArray(); return Expression.Lambda( eventInfo.EventHandlerType, Expression.Call(Expression.Constant(action), "Invoke", Type.EmptyTypes), parameters ) .Compile(); } private void EventFired() { Binding = _propertyInfo.GetValue(AssociatedObject, null); } } } 

 using System; using System.Diagnostics; using System.Linq; using System.Linq.Expressions; using System.Reflection; using System.Windows; using System.Windows.Interactivity; using Expression = System.Linq.Expressions.Expression; namespace DependecyPropertyBehaviorNamesapce { public class DependecyPropertyBehavior : Behavior<DependencyObject> { private Delegate _handler; private EventInfo _eventInfo; private PropertyInfo _propertyInfo; public static readonly DependencyProperty BindingProperty = DependencyProperty.RegisterAttached( "Binding", typeof(object), typeof(DependecyPropertyBehavior), new FrameworkPropertyMetadata { BindsTwoWayByDefault = true } ); public object Binding { get { return GetValue(BindingProperty); } set { SetValue(BindingProperty, value); } } public string Property { get; set; } public string UpdateEvent { get; set; } protected override void OnAttached() { Type elementType = AssociatedObject.GetType(); // Getting property. if (Property == null) { PresentationTraceSources.DependencyPropertySource.TraceData( TraceEventType.Error, 1, "Target property not defined." ); return; } _propertyInfo = elementType.GetProperty(Property, BindingFlags.Instance | BindingFlags.Public); if (_propertyInfo == null) { PresentationTraceSources.DependencyPropertySource.TraceData( TraceEventType.Error, 2, string.Format("Property \"{0}\" not found.", Property) ); return; } // Getting event. if (UpdateEvent == null) return; _eventInfo = elementType.GetEvent(UpdateEvent); if (_eventInfo == null) { PresentationTraceSources.MarkupSource.TraceData( TraceEventType.Error, 3, string.Format("Event \"{0}\" not found.", UpdateEvent) ); return; } _handler = CreateDelegateForEvent(_eventInfo, EventFired); _eventInfo.AddEventHandler(AssociatedObject, _handler); } protected override void OnDetaching() { if (_eventInfo == null) return; if (_handler == null) return; _eventInfo.RemoveEventHandler(AssociatedObject, _handler); } protected override void OnPropertyChanged(DependencyPropertyChangedEventArgs e) { if (e.Property.Name != "Binding") return; if (AssociatedObject == null) return; if (_propertyInfo == null) return; object oldValue = _propertyInfo.GetValue(AssociatedObject, null); if (oldValue.Equals(e.NewValue)) return; if (_propertyInfo.CanWrite) _propertyInfo.SetValue(AssociatedObject, e.NewValue, null); base.OnPropertyChanged(e); } private static Delegate CreateDelegateForEvent(EventInfo eventInfo, Action action) { ParameterExpression[] parameters = eventInfo .EventHandlerType .GetMethod("Invoke") .GetParameters() .Select(parameter => Expression.Parameter(parameter.ParameterType)) .ToArray(); return Expression.Lambda( eventInfo.EventHandlerType, Expression.Call(Expression.Constant(action), "Invoke", Type.EmptyTypes), parameters ) .Compile(); } private void EventFired() { if (AssociatedObject == null) return; if (_propertyInfo == null) return; Binding = _propertyInfo.GetValue(AssociatedObject, null); } } }