EventArgs{T}

namespace App1
{
    public class EventArgs<T> : EventArgs
    {
        /// <summary>
        /// Initializes a new instance of the <see cref="EventArgs"/> class.
        /// </summary>
        /// <param name="value">Value of the argument</param>
        public EventArgs(T value)
        {
            this.Value = value;
        }

        /// <summary>
        /// Gets the value of the event argument
        /// </summary>
        public T Value { get; private set; }
    }
}