A more general INotifyPropertyChangedHandler extension method for strongly typed reflection

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  1. static class ExtensionMethods
  2. {
  3.     public static void Raise<TValue>(this PropertyChangedEventHandler handler, Expression<Func<TValue>> propertySelector)
  4.     {
  5.         var memberExpression = propertySelector.Body as MemberExpression;
  6.  
  7.         if (handler == null || memberExpression == null)
  8.         {
  9.             return;
  10.         }
  11.  
  12.         var sender = ((ConstantExpression)memberExpression.Expression).Value;
  13.         handler(sender, new PropertyChangedEventArgs(memberExpression.Member.Name));
  14.     }
  15. }

Use this as an extension method like this on a class that implements INotifyPropertyChanged

  1. class SomeClass : INotifyPropertyChanged
  2. {
  3.     private string _someProperty;
  4.  
  5.     public string SomeProperty
  6.     {
  7.         get
  8.         {
  9.             return this._someProperty;
  10.         }
  11.         set
  12.         {
  13.             if (value != this._someProperty)
  14.             {
  15.                 this._someProperty = value;
  16.                 this.PropertyChanged.Raise(() => this.SomeProperty);
  17.             }
  18.         }
  19.     }
  20.  
  21.     public event PropertyChangedEventHandler PropertyChanged;
  22. }

Good luck :)

-Kristof

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