Override of Sitecore.Analytics.Pipelines.StartTracking.ProcessQueryStringCampaign to prevent campaign triggering when the end date has passed.

ProcessQueryStringCampaignEx.cs

using System;
using Sitecore.Abstractions;
using Sitecore.Analytics.Pipelines.StartTracking;
using Sitecore.Data;

namespace YOURNAMESPACE.Analytics.Pipelines.StartTracking
{
    public class ProcessQueryStringCampaignEx : ProcessQueryStringCampaign
    {
        public ProcessQueryStringCampaignEx() : base() { }

        public ProcessQueryStringCampaignEx(BaseLog logger, string campaignQueryStringKey) : base(logger, campaignQueryStringKey) { }

        protected override void TriggerCampaign(string campaign)
        {
            var campaignDefinition = !ShortID.IsShortID(campaign) ? (!ID.IsID(campaign) ? FindCampaignByName(campaign) : FindCampaignById(new ID(campaign))) : FindCampaignById(ShortID.DecodeID(campaign));
            if (campaignDefinition == null)
            {
                Logger.Error("Campaign not found: " + campaign, typeof(ProcessQueryStringCampaign));
            }
            else
            {
                // Don't trigger the campaign if it's expired.
                // NEW
                if (DateTime.UtcNow >= campaignDefinition.EndDate)
                {
                    return;
                }
                // END NEW

                var campaignId1 = CurrentTracker.Session.Interaction.CampaignId;
                var trafficType1 = CurrentTracker.Session.Interaction.TrafficType;
                CurrentTracker.CurrentPage.TriggerCampaign(campaignDefinition);
                var campaignId2 = CurrentTracker.Session.Interaction.CampaignId;
                var trafficType2 = CurrentTracker.Session.Interaction.TrafficType;
                var nullable = campaignId1;
                var campaignId3 = CurrentTracker.Session.Interaction.CampaignId;
                if ((nullable.HasValue == campaignId3.HasValue ? (nullable.HasValue ? (nullable.GetValueOrDefault() != campaignId3.GetValueOrDefault() ? 1 : 0) : 0) : 1) != 0)
                    SubscribeCampaignIdRollbackToOnCurrentPageCancelled(campaignId2);
                if (trafficType1 == trafficType2)
                    return;
                SubscribeTrafficTypeRollbackToOnCurrentPageCancelled(trafficType2);
            }
        }
    }
}