Initial

BrightSharp/Mvvm/ViewModelBase.cs

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+using System;
+using System.Collections.Generic;
+using System.ComponentModel;
+using System.Linq.Expressions;
+using System.Reflection;
+using System.Windows;
+
+namespace BrightSharp.Mvvm
+{
+    public class ObservableObject : INotifyPropertyChanged
+    {
+        static readonly DependencyObject designTimeObject = new DependencyObject();
+        public static bool IsInDesignTime
+        {
+            get
+            {
+                try
+                {
+                    return DesignerProperties.GetIsInDesignMode(designTimeObject);
+                }
+                catch(Exception)
+                {
+                    return true;
+                }
+
+            }
+        }
+
+        protected PropertyChangedEventHandler PropertyChangedHandler
+        {
+            get
+            {
+                return PropertyChanged;
+            }
+        }
+
+        public ObservableObject()
+        {
+        }
+
+        protected static string GetPropertyName<T>(Expression<Func<T>> propertyExpression)
+        {
+            if(propertyExpression == null)
+            {
+                throw new ArgumentNullException("propertyExpression");
+            }
+            MemberExpression body = propertyExpression.Body as MemberExpression;
+            if(body == null)
+            {
+                throw new ArgumentException("Invalid argument", "propertyExpression");
+            }
+            PropertyInfo property = body.Member as PropertyInfo;
+            if(property == null)
+            {
+                throw new ArgumentException("Argument is not a property", "propertyExpression");
+            }
+            return property.Name;
+        }
+
+        protected virtual void RaisePropertyChanged<T>(Expression<Func<T>> propertyExpression)
+        {
+            PropertyChangedEventHandler handler = PropertyChanged;
+            if(handler != null)
+            {
+                handler(this, new PropertyChangedEventArgs(GetPropertyName(propertyExpression)));
+            }
+        }
+
+        protected Boolean Set<T>(Expression<Func<T>> propertyExpression, ref T field, T newValue)
+        {
+            if(EqualityComparer<T>.Default.Equals(field, newValue))
+            {
+                return false;
+            }
+            field = newValue;
+            this.RaisePropertyChanged(propertyExpression);
+            return true;
+        }
+
+        protected bool Set<T>(string propertyName, ref T field, T newValue)
+        {
+            if(EqualityComparer<T>.Default.Equals(field, newValue))
+            {
+                return false;
+            }
+            field = newValue;
+            RaisePropertyChanged(propertyName);
+            return true;
+        }
+
+        protected void RaisePropertyChanged(string propertyName)
+        {
+            PropertyChangedEventHandler handler = PropertyChanged;
+            if(handler != null)
+            {
+                handler(this, new PropertyChangedEventArgs(propertyName));
+            }
+        }
+
+        public event PropertyChangedEventHandler PropertyChanged;
+    }
+}