File: Core\CSharp\System\Windows\Input\KeyEventHandler.cs
Project: wpf\src\PresentationCore.csproj (PresentationCore)

using System;
namespace System.Windows.Input 
{
    /// <summary>
    ///     The delegate to use for handlers that receive KeyEventArgs.
    /// </summary>
    /// <ExternalAPI Inherit="true"/>
    public delegate void KeyEventHandler(object sender, KeyEventArgs e);
}