Sample: Update next birthday using a custom workflow activity

Download the complete sample here Custom workflow activities sample.


Internet connection is required to download the sample project and to restore the NuGet packages used in the sample project.


The following custom field must exist for this custom workflow activity to work:

  • Contact.new_nextbirthday


The following sample workflow activity returns the next birthday. Use this in a workflow that sends a birthday greeting to a customer.


using System;
using System.Activities;
using System.Collections;
using System.Reflection;

using Microsoft.Xrm.Sdk;
using Microsoft.Xrm.Sdk.Messages;
using Microsoft.Xrm.Sdk.Query;
using Microsoft.Xrm.Sdk.Workflow;

namespace Microsoft.Crm.Sdk.Samples
    /// <summary>
    /// Activity will return the next upcoming birthday that has just passed
    /// If this year's birthday has not yet occurred, it will return this year's birthday
    /// Otherwise, it will return the birthday for next year
    /// A workflow can timeout when on this date
    /// </summary>
    public sealed partial class ReleaseScenario_UpdateNextBirthday : CodeActivity
        protected override void Execute(CodeActivityContext executionContext)
            IWorkflowContext context = executionContext.GetExtension<IWorkflowContext>();

            //Create an Organization Service
            IOrganizationServiceFactory serviceFactory = executionContext.GetExtension<IOrganizationServiceFactory>();
            IOrganizationService service = serviceFactory.CreateOrganizationService(context.InitiatingUserId);

            //Retrieve the contact id
            Guid contactId = this.Contact.Get(executionContext).Id;

            //Create the request
            RetrieveRequest request = new RetrieveRequest();
            request.ColumnSet = new ColumnSet(new string[] { "birthdate" });
            request.Target = new EntityReference(EntityName.Contact, contactId);

            //Retrieve the entity to determine what the birthdate is set at
            Entity entity = (Entity)((RetrieveResponse)service.Execute(request)).Entity;

            //Extract the date out of the entity
            DateTime? birthdate;
            if (entity.Contains(ContactAttributes.Birthdate))
                birthdate = (DateTime?)entity[ContactAttributes.Birthdate];
                birthdate = null;

            //Check to see if the current birthday is set. We don't want the activity to fail if the birthdate is not set
            if (birthdate == null)

            //Calculate the next birthdate. Encapsulated in a methdo so that the method can be used in the test case for verification purposes
            DateTime nextBirthdate = CalculateNextBirthday(birthdate.Value);

            //Update the next birthday field on the entity
            Entity updateEntity = new Entity(EntityName.Contact);
            updateEntity.Id = contactId;
            updateEntity["new_nextbirthday"] = nextBirthdate;


        //Define the properties
        [Input("Update Next Birthdate for")]
        public InArgument<EntityReference> Contact { get; set; }

        private DateTime CalculateNextBirthday(DateTime birthdate)
            DateTime nextBirthday = new DateTime(birthdate.Year, birthdate.Month, birthdate.Day);

            //Check to see if this birthday occurred on a leap year
            bool leapYearAdjust = false;
            if (nextBirthday.Month == 2 && nextBirthday.Day == 29)
                //Sanity check, was that year a leap year
                if (DateTime.IsLeapYear(nextBirthday.Year))
                    //Check to see if the current year is a leap year
                    if (!DateTime.IsLeapYear(DateTime.Now.Year))
                        //Push the date to March 1st so that the date arithmetic will function correctly
                        nextBirthday = nextBirthday.AddDays(1);
                        leapYearAdjust = true;
                    throw new Exception("Invalid Birthdate specified", new ArgumentException("Birthdate"));

            //Calculate the year difference
            nextBirthday = nextBirthday.AddYears(DateTime.Now.Year - nextBirthday.Year);

            //Check to see if the date was adjusted
            if (leapYearAdjust && DateTime.IsLeapYear(nextBirthday.Year))
                nextBirthday = nextBirthday.AddDays(-1);

            return nextBirthday;

See also

Workflow extensions
Tutorial: Create workflow extension
Sample: Create a custom workflow activity
Sample: Calculate a credit score with a custom workflow activity