How to concatenate fields from two standard objects?

Question

I've create a function that pulls Id to a set, and a Map to contact that pulls id and in the SOQL statement compare the whoId from Task to Contact.ID then concatenate(Task.subject, Task.Type, Contact.Name) 3 fields to one custom field. I'm not sure how to proceed from here?

 public void ListOfTaskIds(list<Task> TaskEventList) {
        Set<ID> whoIdSet = new Set<ID>();
        for(Task e: TaskEventList){
            if(e.whoId != null){
                whoIdSet.add(e.WhoId);
            }
        }
        System.Debug('>>>>>>> the value of:' + whoIdSet);
        Map<ID, Contact> contactMap = new Map<ID, Contact>([select id, name from contact where id in :whoIdSet]);

    }

Answer 1

I don't know what you mean by a "slandered" object. I'll assume you meant to say "Standard" object.

I don't know which sobject your custom field belongs to either. So I'll assume it's in the Task sobject (ie., Task.Your_Custom_Field__c).

I also don't understand your description of the code. But from reading it, I'll assume you're asking the community how to concatenate Task.Subject, Task.Type, and Contact.Name now that you've compiled your WhoId's and have a map of Contacts.

Here's the next block of code that I think you're looking for:

// Concatenate to Task.Your_Custom_Field__c
for (Task e : TaskEventList) {
    Contact c = contactMap.get(e.whoId);

    if (c != null) { 
        e.your_custom_field__c = e.subject + ' ' + e.type + ' ' + c.name;
    }
}

Hope that helps!

Answer 2

You can do this for concatenating more than one Id.

String matrixId = '' + Account.Id + Contact.Id;

or

String matrixId = String.valueof(Account.Id) + String.valueof(Contact.Id)