Outputlink vs Commandlink

Outputlink vs Commandlink Apex:outputLink – A link to a URL. This component is rendered in HTML as an anchor tag with an href attribute. Like its HTML equivalent, the body of an <apex:outputLink> is the text or image that displays as the link. To add query string parameters to a link, use nested <apex:param> components. <apex:outputlink value="https://www.google.co.in"> Google </apex:outputlink> <apex:outputlink value="/{!r.Id}"> {!r.Name} </apex:outputlink> apex:commandLink – A link that executes an action defined by a controller, and then either refreshes the current page, or navigates to a different page based on the PageReference variable that is returned by the action.  An <apex:commandLink> component must always be a child of an <apex:form> component. To add request parameters to an <apex:commandLink>, use nested <apex:param> components. <apex:commandLink value="Google" action="https://www.google.co.in"/> <apex:commandLink value="Delete" action="{!dodelete}">       <apex:param name="eid" value="{!E.Id}" assignTo="{!rId}"/> </apex:commandLink> public pagereference doDelete(){  delete [select id from Employee__c where id =: rid];  return(new pagereference ('/apex/commandlink1').setredirect(true));     } <apex:commandLink value="Show Data" action="{!doShow}">    <apex:param name="aid" value="{!A.Id}" assignTo="{!rId}"/> </apex:commandLink> public PageReference doShow() { //return(new pagereference('/apex/showPage?id='+rId).Setredirect(true));     pagereference ref = new pagereference('/apex/showPage?id='+rId);     ref.setredirect(true);     return ref;     }

Outputlink with parameters

1. <apex:page standardController="Contact">
2.     <apex:outputLink value="http://google.com/search">
3.         Search Google
4.         <apex:param name="q" value="{!contact.name}"/>
5.     </apex:outputLink>
6. </apex:page>

  

Example 2:

1. <apex:page standardController="Account" recordSetVar="records">
2.   <apex:form >
3.       <apex:pageBlock >
4.           <apex:pageBlockTable value="{!records}" var="r">
5.               <apex:column headerValue="Account Name" >
6.                   <apex:outputlink value="/{!r.Id}"> {!r.Name} </apex:outputlink>
7.               </apex:column>
8.               <apex:column headerValue="Account Phone" value="{!r.Phone}"/> 
9.           </apex:pageBlockTable>
10.       </apex:pageBlock>
11.   </apex:form>
12. </apex:page>

On clicking the account name the account detail page will open as the account name is hyper linked with its record id in apex:outputlink statement in vf page

Delete record using commandlink

1. <apex:page controller="CommandLinkCls">
2.  <apex:form >
3.      <apex:pagemessages ></apex:pagemessages>
4.      <apex:pageBlock rendered="{!IF(lstE.size ==0,false,true)}">
5.      
6.          <apex:pageBlockTable value="{!lstE}" var="E">
7.              <apex:column headerValue="Action">
8.                  
9.       <apex:commandLink value="Delete" action="{!dodelete}">
10.    <apex:param name="eid" value="{!E.Id}" assignTo="{!rId}"/>
11.       </apex:commandLink>
12.              
13.              </apex:column>
14.              <apex:column headerValue="Employee ID" value="{!E.Name}"/>
15.              
16.          </apex:pageBlockTable>
17.      </apex:pageBlock>
18.      
19.  </apex:form>
20. </apex:page>

1. public with sharing class CommandLinkCls {
2. 
   
3.     public PageReference doshow() {
4.         return null;
5.     }
6. 
   
7. 
   
8.     public List<Employee__c> lstE{get;set;}
9.    
10.     public CommandLinkCls(){
11.     lstE = new List<Employee__c>();
12.     lstE = [select id,name,Email_Address__c,Employee_Name__c from Employee__c];
13.                                 
14.     if(lstE.size() == 0){
15.     ApexPages.Message myMsg = new ApexPages.Message(ApexPages.Severity.FATAL, 'Data not found.............');
16.                                     apexpages.addMessage(myMsg);
17.                                 }
18.                                 
19.                             }
20.     
21.     public String rId{get;set;}
22.     
23.     public pagereference doDelete(){
24.         delete [select id from Employee__c where id =: rid];
25.         return (new pagereference('/apex/commandlink1').setredirect(true));
26.     }
27. }

Redirecting to other page using commandlink 

1. <apex:page showHeader="false" controller="ShowDataclass">
2.  <apex:form >
3.      <apex:pageBlock >
4.          <apex:pageBlockTable value="{!lstA}" var="A">
5.              <apex:column headerValue="Action">
6.                  <apex:commandLink value="{!A.Name}" action="{!doShow}">
7.                      <apex:param name="aid" value="{!A.Id}" assignTo="{!rId}"/>
8.                  </apex:commandLink>
9.              </apex:column>
10.              <apex:column headerValue="Account Name" value="{!A.Name}"/>
11.          </apex:pageBlockTable>
12.      </apex:pageBlock>
13.  </apex:form>
14. </apex:page>

1. public with sharing class ShowDataclass {
2.      public String rId{get;set;}
3.      public List<Account> lstA{get;set;}
4.       public ShowDataclass(){
5.         lstA = new List<Account>();
6.         lstA = [select id,name,phone from Account];
7.        }
8.     public PageReference doShow() {
9.         //return (new pagereference('/apex/showPage?id='+rId).setredirect(true));
10.         pagereference ref = new pagereference('/apex/showPage?id='+rId);
11.         ref.setredirect(true);
12.         return ref;
13.     }  
14. }

showPage

1. <apex:page showHeader="false" controller="ShowDataDisplayCls">
2.   <apex:form >
3.       <apex:pageBlock >
4.           <apex:pageblocktable value="{!lstA}" var="A">
5.               <apex:column headerValue="Account Name" value="{!A.Name}"/>
6.               <apex:column headerValue="Account Phone" value="{!A.Phone}"/>
7.           </apex:pageblocktable>
8.       </apex:pageBlock>
9.   </apex:form>
10. </apex:page>

1. public with sharing class ShowDataDisplayCls {
2. 
   
3.     public List<Account> lstA{get;set;}
4.     public ShowDataDisplayCls(){                        //Constructor 
5.         lstA = new List<Account>();
6.         
7.         lstA = [select id, name, phone from Account where id = :apexpages.currentpage().getparameters().get('id')];
8.     }
9. }