Action Function Actin Support Action Region Action Poller
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Action Function: –
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Action Function is used in the Visualforce page to call the Service Side method using JavaScript and
does not add the Ajax Request before calling the Controller method.

   <apex:actionFunction name=”myactionfun” action=”{!actionFunctionTest}” reRender=”pgBlock, pbSection” />

Let us talk about above example. In any Javascript Method where the name of ActionFunction
( In our example myactionfun() ) will be invoked, it will call the controller method name
actionFunctionTest. Example myactionfun();

Action Support: –
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As the name indicates action support is used to provide the support to the input field where
we can not get event either manually or external event. It adds the AJAX request to VF page and
then Calls the Controller method. For

For example, if we want to call any server side method when input changes then we will go for
action support because we can not get any event for this.

 <apex:inputText value=”{!dummyString}” >
 <apex:actionSupport event=”onchange” action=”{!actionSupportTest}” reRender=”pgBlock, pbSection” />
 </apex:inputText>

Action Poller: –
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A timer that sends an AJAX request to the server according to a time interval that you specify. Each
request can result in a full or partial page update.

 apex:actionPoller action=”{!incrementCounter}” reRender=”counter” interval=”15″ enabled = “true” />

Enabled attribute is used to make poller as active or inactive by default value is true.
If we provide false then poller will be inactivate.
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VisualForce Page:::------------

<apex:page controller="ActionFuctionSupportDemoController">
    <apex:slds />
  <apex:form >
      <script>
          function javaScriptMethod(){
            alert('Calling Action Function');
            myactionfun();
          }
      </script>
<apex:actionFunction name="myactionfun"  action="{!actionFunctionTest}" reRender="pgBlock, pbSection" />
      <apex:pageBlock title="Test Action Support/Function Test">
          <apex:pageblockSection >
              <apex:inputText value="{!dummyString}" >
                  <apex:actionSupport event="onchange" action="{!actionSupportTest}" reRender="pgBlock, pbSection" />
              </apex:inputText>
             
              <apex:inputcheckbox onclick="javaScriptMethod();" />
             
          </apex:pageblockSection>
      </apex:pageBlock>
      <apex:pageblock title="Output of Action Funtion/Support" id="pgBlock">
          <apex:pageblockSection id="pbSection" >
              {!actionFunTest}
          </apex:pageblockSection>
      </apex:pageblock>
      <apex:pageBlock title="Action Poller Block ">
          <apex:pageBlockSection >
              <apex:outputText value="Watch this counter: {!count}" id="counter"/>
              <apex:actionPoller action="{!incrementCounter}" reRender="counter" interval="10"/>
          </apex:pageBlockSection>
      </apex:pageBlock>
  </apex:form>
</apex:page>
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Apex  Class :---

public class ActionFuctionSupportDemoController{

    public static String actionFunTest { get; set; }
    public static String dummyString { get; set; }
        Integer count = 0;
    public void actionFunctionTest(){
      actionFunTest = 'Value from Action Function';
        }
    public void actionSupportTest(){
      System.debug('#### Action Support Called');
      actionFunTest = 'Value from Action Support '+dummyString;
    }
    public PageReference incrementCounter() {
        count++;
        return null;
    }     
    public Integer getCount() {
        return count;
    }
}
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