Copy all activities associated with an entity to another entity through Plugin in Dynamics CRM 2011

Copy all activities associated with entity to other entity thru Plugin in MS Dyanmcis

Requirement: Suppose you are copying over a record from an entity to another entity and you wanted to copy over the realted activities as well. Suppose you a custom Prospect entity record which have 2 task activites associated with, if you have to copy both tasks to another entity lets says Lead entity along with data.

Following is the Plugin you can use on Update Event.

if (entity.LogicalName == "new_prospect")

           {

  try

      {

         Entity lead = new Entity("lead");

         ColumnSet cols = new ColumnSet();

         cols.AddColumns(new string[] { "new_pipelinestatus", "new_rating", "new_lastname", "new_firstname", "new_businessphone", "new_addressstreet1", "new_city", "new_stateprovince", "new_zippostalcode", "new_updatecounter" });

entity = service.Retrieve("new_prospect", entity.Id, cols);

Guid Lid=  service.Create(lead);

 // copy activities

 var query = new QueryExpression("task");

query.ColumnSet = new ColumnSet(true);

//regardingobjectid this will get all activities of Prospect entity.

query.Criteria.AddCondition(new ConditionExpression("regardingobjectid", ConditionOperator.Equal, entity.Id));

                                           

                                                                                        

var activities = service.RetrieveMultiple(query).Entities;

foreach (var activity in activities)

{

  activity.Attributes.Remove("activityid");

  activity.Id = Guid.NewGuid();

  string regardingaccountype = "lead";

  activity["regardingobjectid"] = new EntityReference(regardingaccountype, Lid);

  service.Create(activity);

}