AutoClose Child Cases whenever a Parent Case is closed

This post is just to expose the way to auto close the child cases, whenever a parent for those child cases are closed, Just some simple workaround to achieve it .

In Case Object, i'm having many closed status vaues, i prefixed it by Closed as per my requirement .
And i dont want to update the already closed unnecesarily.

Code:

1. Trigger AutoCloseChildCases on Case (after update) {
2.   Case[] casesToUpdate = new Case[0];
3. Set<Id>CaseSet = new Set<Id>();
4. for (Integer c=0;c<Trigger.size;c++) {  
5.     if ((Trigger.old[c].Status.contains('Closed')== false) && (Trigger.new[c].Status.contains('Closed')== true)) {
6.   CaseSet.add(Trigger.New[c].Id);
7.   }
8.   }
9.  
10.   If(CaseSet.Size()>0){
11.   Case[] cases = [select Id, Status, ParentId from Case where ParentId in:CaseSet];
12.  
13.   for (Integer i=0;i<Trigger.size;i++) {
14.     if ((Trigger.old[i].Status.contains('Closed')== false) && (Trigger.new[i].Status.contains('Closed')== true)) {
15.       for (Integer j=0;j<cases.size();j++) {
16.         if (cases[j].ParentId == Trigger.new[i].Id) {
17.           if(cases[j].Status.contains('Closed')==false)
18.           {
19.           cases[j].Status = 'Closed';
20.           casesToUpdate.add(cases[j]);
21.           }
22.         } //end if
23.       } //end for
24.     } //end if
25.   } //end for
26. } //update the list
27. if(casesToUpdate.size()>0){
28.   update casesToUpdate;
29.   }
30. } //end trigger

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