Hi eveyone. I'm writing a VF page with a controller exstention and i have 2 problems. In my page when you fill the field Merge To Case and click Merge all the attachments of one case need to be reparented.
First Problem Am I passing Merge_To_Case in the right way between VF and CaseControllerExstention.
Second When i click on merge button , it's seems to do nothing and I don't understand why.
I hope you can help me.Here my code:
VF page:
<apex:page standardController="Case" extensions="CaseMergeExtension" showHeader="true" sidebar="false">
<apex:form >

<apex:actionfunction name="MergeCase" action="MergeCase" >
<apex:param name="Casetomerge" value="" assignTo="{!Case.Merge_To_Case__c}" />
</apex:actionFunction>

<apex:sectionHeader description="Case Merging Page" title="Case">
</apex:sectionHeader>
  <apex:pageBlock title="Case To BE Merged {!Case.CaseNumber}">
      <apex:pageBlockButtons location="top">
       <apex:commandButton value="Merge" onClick="MergeCase('{!Case.Merge_To_Case__c}')" />    
      </apex:pageBlockButtons>
       <apex:pageBlockSection >
      <apex:pageBlockSectionItem >
               <apex:outputLabel for="FondereCasi">Merge To Case</apex:outputLabel>
               <apex:inputField id="FondereCasi" value="{!Case.Merge_To_Case__c}"/>
      </apex:pageBlockSectionItem> 
      </apex:pageBlockSection> 
      <br/><br/><h1>ATTENTION !</h1>
      <p><b>When you click Merge button the case {!Case.CaseNumber} will be merge with {!Case.Merge_To_Case__c}</b></p> 
  </apex:pageBlock>
</apex:form>
  <!-- End Default Content REMOVE THIS -->
</apex:page>

and here the Apex Exstension Controller:
public class CaseMergeExtension {
    // ApexPages.StandardSetController must be instantiated
    // for standard list controllers
    public Case caso{get;set;}
    public CaseMergeExtension(ApexPages.StandardController stdcontroller) {
          this.caso = (Case)stdController.getRecord();
    }
    
    //pass Merge_To_Case__c from VF page in Casetomerge variable
    public String Casetomerge{get;set;}
    
    //function used to merge Case and case referenced by Merge_To_Case__c field 
    
    public void MergeCase(){
         //take the ID of Case referende By Merge_To_Case__c field and put it in CaseIDF variable
          Map<Id, Case> CaseMap = new Map<Id, Case>([
                           SELECT Id
                           FROM case
                           where CaseNumber=: 'Casetomerge']);
         List<Id> CaseId= new List<Id>(CaseMap.keySet());
         Id CaseIDF=CaseId.get(0);
        
        //Create a List of all Attachment from caso Object, that need to be reparented
         Map<id,List<Attachment>> AttachMap=new Map<Id,List<Attachment>>();
            for(Case cs:[select id, (select id from attachments) from case where ID=:caso.Id]){
                    AttachMap.put(cs.id,cs.attachments);
            }
        List<Attachment> attach= AttachMap.get(caso.Id);
        
        //reparent all the Attachemnts fro caso to the Case referenced by Merge_To_Case__c field
        for(Attachment a:attach ){
           a.parentid=CaseIDF;
        }
        update caso;
      }
}