Trigger to Prevent Deleting a Record based on Record Type

Fresh off of a full week of Development Classes in Washington D.C. it was time to put that knowledge to work! Here's the scenario:

We need to prevent a user from deleting a contact when they are a particular record type. I put this together in my developer account so it is a rather contrived example but it can be altered to fit the needs of anyone...

Trigger:

/*
If a user attempts to delete under these conditions,
prevent the delete and display this message at the top of the Contact page layout:
“You are not permitted to delete a Contact with a recrod type of 'Other'.”.
*/

trigger TestContactBeforeDeleteTrigger on Contact (before delete) {


List<RecordType> recType = [select id from RecordType where name = 'Record Type A' AND sobjecttype = 'Contact' AND IsActive = TRUE limit 1];

 if(!recType.isempty()){
String RecordTypeAid = rectype[0].id;

  for(Contact con: trigger.old){

       if(con.RecordTypeId == RecordTypeAid){
         con.addError('You are not permitted to delete an account with a record type of "Other"');
             }
        }
}
}


Test Class:

/*
Test class for TestContactBeforeDeleteTrigger
*/

@isTest
private class TestBeforeDelete {

    static testMethod void myUnitTest() {
     
List<RecordType> recType = [select id from RecordType where name = 'Record Type A' AND sobjecttype = 'Contact' AND IsActive = TRUE limit 1];

  if(!recType.isempty()){
String RecordTypeAid = rectype[0].id;
   
Contact c1 = new ContCt();
c1.LastName = 'Test Last Name for Trigger';
c1.RecordTypeID = RecordTypeAid;

        insert c1;
   
        try{
         delete c1;
        }
        catch (dmlexception e){
       
         system.assert(e.getMessage().contains('You are not permitted to delete an account with a record type of "Other"'),
         e.getMessage() );
      }
    }
    }
}

A special thanks to Peter Gruhl who taught the DEV501 class. The class was quite a bit to handle and he taught it VERY well. Thanks Peter!

This code was updated on 6/26/2013 to remove any references to hard coded Record Type IDs. I have included a SOQL line that pulls the RecordTypeID from the system dynamically so this will work from Sandbox to Production where the record type ids are different.