xenadmin/XenCenterLib/EventHandlerExtensions.cs

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 *     following disclaimer. 
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 *     following disclaimer in the documentation and/or other 
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 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
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namespace System
{
    public static class EventHandlerExtensions
    {
        //Raise with no args
        public static void Raise(this EventHandler handler, object sender)
        {
            if (handler != null)
            {
                handler(sender, EventArgs.Empty);
            }
        }
        /// <summary>
        /// Raise with args
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="handler"></param>
        /// <param name="sender"></param>
        /// <param name="args"></param>
        public static void Raise<T>(this EventHandler<T> handler, object sender, T args) 
            where T:EventArgs
        {
            if (handler != null)
            {
                handler(sender, args);
            }
        }
        /// <summary>
        /// Lazy creation of args
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="handler"></param>
        /// <param name="sender"></param>
        /// <param name="args"></param>
        public static void Raise<T>(this EventHandler<T> handler, object sender, Func<T> args)
            where T : EventArgs
        {
            if (handler != null)
            {
                handler(sender, args());
            }
        }
    }
}