/// <summary>
/// Initializes a new instance of the <see cref="AuditInfo{T}"/> class.
/// </summary>
/// <param name="requestContext"> The request context to extract user and action information. </param>
public AuditInfo(RequestContext requestContext)
{
requestContext
.ArgumentMustNotBeNull("requestContext")
.ArgumentPropertyMustNotBeNull("requestContext", "RouteData", x => x.RouteData)
.ArgumentPropertyMustNotBeNull("requestContext", "RouteData.Values", x => x.RouteData.Values)
.ArgumentPropertyMustNotBeNull("requestContext", "HttpContext", x => x.HttpContext)
.ArgumentPropertyMustNotBeNull("requestContext", "HttpContext.User", x => x.HttpContext.User);
this.Action = requestContext.RouteData.Values.Aggregate(string.Empty, (c, x) => c + "=>" + x.Value);
this.User = requestContext.HttpContext.User.Identity.Name;
}