PhantomJS - onCallback()

The onCallback method is used to pass values from a webpage to a webpage object and it is done using the window.callPhantom() method. This method internally invokes the onCallback function.

Syntax

Its syntax is as follows −

var wpage = require('webpage').create(); 
wpage.onCallback = function(data) {}

Example

The following example shows the use of onCallback() method.

var wpage = require('webpage').create(); 
wpage.onCallback = function(str) { 
   console.log(str + " phantomJs"); 
} 
wpage.open('http://localhost/tasks/callback.html', function(status) { 
   console.log(status);  
   phantom.exit(); 
});

callback.html

<html> 
   <head></head> 
   <body> 
      <script type = "text/javascript"> 
         var a = window.callPhantom("Welcome to "); 
      </script> 
   </body> 
</html>

The above program generates the following output.

Welcome to phantomJs 
Success

phantomjs_webpage_module_events_callbacks.htm