MVVM模式应用 之NotificationObject类

public abstract class NotificationObject : INotifyPropertyChanged
{
    public event PropertyChangedEventHandler PropertyChanged;
 
    protected virtual void RaisePropertyChanged(string propertyName)
    {
        PropertyChangedEventHandler handler = this.PropertyChanged;
        if (handler != null)
        {
            handler(this, new PropertyChangedEventArgs(propertyName));
        }
    }
 
    protected void RaisePropertyChanged(params string[] propertyNames)
    {
        if (propertyNames == null) throw new ArgumentNullException("propertyNames");
 
        foreach (var name in propertyNames)
        {
            this.RaisePropertyChanged(name);
        }
    }
 
    protected void RaisePropertyChanged<T>(Expression<Func<T>> propertyExpression)
    {
        var propertyName = ExtractPropertyName(propertyExpression);
        this.RaisePropertyChanged(propertyName);
    }
 
    public static string ExtractPropertyName<T>(Expression<Func<T>> propertyExpression)
    {
        if (propertyExpression == null)
        {
            throw new ArgumentNullException("propertyExpression");
        }
 
        var memberExpression = propertyExpression.Body as MemberExpression;
        if (memberExpression == null)
        {
            throw new ArgumentException("PropertySupport_NotMemberAccessExpression_Exception", "propertyExpression");
        }
 
        var property = memberExpression.Member as PropertyInfo;
        if (property == null)
        {
            throw new ArgumentException("PropertySupport_ExpressionNotProperty_Exception", "propertyExpression");
        }
 
        var getMethod = property.GetGetMethod(true);
        if (getMethod.IsStatic)
        {
            throw new ArgumentException("PropertySupport_StaticExpression_Exception", "propertyExpression");
        }
 
        return memberExpression.Member.Name;
    }
}