javascript - Catching the response of the iFrame once receiving the response -

i posting message iframe. iframe returns response boolean. need catch response when response arrives parent window iframe. code not working. idea onthis?

iframe

<iframe id="opiframe"  src="https://localhost:9443/oauth2/session" >  </iframe> 

i'm sending message iframe periodically

var iframe = document.getelementbyid("opiframe");      setinterval(function(){          message ='test' ;         console.log('request rp: ' + message);          iframe.contentwindow.postmessage(message,"https://localhost:9443/oauth2/session");       },6000); 

what need receive response of iframe periodically. code working. added eventlistener iframe below.

 iframe.addeventlistener("message",test,false);     function test(event){         alert("test");     } 

but not firing periodically

it simple: added listener on iframe (as element of parent window's dom), instead of on iframe's window. fix , works:

iframe.contentwindow.addeventlistener("message",test,false);