/// <summary>
/// Extends BeginInvoke so that when a state object is not needed, null does not need to be passed.
/// <example>
/// propertychangingeventhandler.BeginInvoke(sender, e, callback);
/// </example>
/// </summary>
public static IAsyncResult BeginInvoke(this PropertyChangingEventHandler propertychangingeventhandler, Object sender, PropertyChangingEventArgs e, AsyncCallback callback)
{
if (propertychangingeventhandler == null)
{
throw new ArgumentNullException("propertychangingeventhandler");
}
return(propertychangingeventhandler.BeginInvoke(sender, e, callback, null));
}
