added alter queryable service.

Demo/DynamicQueries/ContactQueryableProvider.cs

@@ -6,6 +6,15 @@ using System.Threading.Tasks;
 
 namespace Demo.DynamicQueries
 {
+    public class SearchContactParamsService : IAlterQueryableService<Contact, Contact, SearchContactParams>
+    {
+        public Task<IQueryable<Contact>> AlterQueryableAsync(IQueryable<Contact> query, IDynamicQueryParams<SearchContactParams> dynamicQuery, CancellationToken cancellationToken = default)
+        {
+            var safe = dynamicQuery.GetParams()?.SearchDisplayName;
+            return Task.FromResult(query.Where(t => t.DisplayName.Contains(safe)));
+        }
+    }
+
     public class ContactQueryableProvider : IQueryableProvider<Contact>
     {
         public Task<IQueryable<Contact>> GetQueryableAsync(object query, CancellationToken cancelllationToken = default)

Demo/Startup.cs

@@ -63,7 +63,8 @@ namespace Demo
         {
             services.AddTransient<IQueryableProvider<Contact>, ContactQueryableProvider>();
             services.AddDynamicQuery<Contact>();
-            services.AddDynamicQueryWithParams<Contact, SearchContactParams>(name: "SearchContacts");
+            services.AddDynamicQueryWithParams<Contact, SearchContactParams>(name: "SearchContacts")
+                .AddAlterQueryableWithParams<Contact, SearchContactParams, SearchContactParamsService>();
         }
 
         private void AddCommands(IServiceCollection services)