gistfile1.txt

using System.Collections.Generic;
using System.Linq;
using System.Web.Mvc;
using Orchard;
using Orchard.Caching;
using Orchard.Environment.Configuration;
using Orchard.Environment.Extensions;
using Orchard.OutputCache.Filters;
using Orchard.OutputCache.Models;
using Orchard.OutputCache.Services;
using Orchard.Services;
using Orchard.Themes;

namespace Patient.Framework.Caching.OutputCache {
    [OrchardFeature("Patient.Framework.Caching.OutputCache")]
    [OrchardSuppressDependency("Orchard.OutputCache.Filters.OutputCacheFilter")]
    public class OutputCacheFilterOverride : OutputCacheFilter {
    
        public OutputCacheFilterOverride(
                ICacheManager cacheManager,
                IOutputCacheStorageProvider cacheStorageProvider,
                ITagCache tagCache,
                IDisplayedContentItemHandler displayedContentItemHandler,
                IWorkContextAccessor workContextAccessor,
                IThemeManager themeManager,
                IClock clock,
                ICacheService cacheService,
                ISignals signals,
                ShellSettings shellSettings) :
                base(
                    cacheManager, cacheStorageProvider, tagCache, displayedContentItemHandler, workContextAccessor,
                    themeManager, clock, cacheService, signals, shellSettings) {
        }

        protected override IDictionary<string, object> GetCacheKeyParameters(System.Web.Mvc.ActionExecutingContext filterContext) {
            var result = base.GetCacheKeyParameters(filterContext);
            
            var ignoreList = new List<string> { "utm1", "utm2" };
            
            // you could remove stuff from the result here which you dont wanna cache by in terms of the querystring
            if (result != null && result.Any()) { 
                foreach(var item in ignoreList { 
                    if (result.ContainsKey(item)) {
                        result.Remove(item);
                    }
                }
            }
            
            return result;
        }
    }
}