Populating field automatically

Question

My requirement is once any user creates a new task, and the Related to value is "sales", the field Campaign will be updated automatically with the value from Related To field.

The data type of both Campaign and Related to are lookup.how would I accomplish this?

Answer 1

Since the Related to (What) field on the Task object is a polymorphic field, first you need to check what kind of record the task record has been created for. and then you can assign the Campaign field on a before trigger based on your requirements, just like this:

trigger TaskTrigger on Task (before insert) {
    
    for (Task t : Trigger.new) {
        // replace 'Sales' with your Object API Name
        if (t.WhatId.getSobjectType().getDescribe().getName() == 'Sales') {
            // update below field with your Campaign API Field name
            t.Campaign__c = t.WhatId;
        }
    }
}

useful links to look at:

• Trigger Context Variables
• ID Class
• DescribeSObjectResult

Hope this helps with your question.