how to return variable from the function called by onreadystatechange=function() [duplicate]

Answer 1

To make your code work you can use closures and pass functions as parameters.
2 properties javascript is very good at.

snappyajaxfunction(url, fn)
{
   var request...

   request.onreadystatechange=function() 
    { 
        if (request.readyState==4)
        {   
           fn(request.responseText);     
        }           
    };             
   request.open("GET",url,true); 
   request.send(null);
}

to use it you can build a function like

var doSomething = function(response){
  alert(response);
};
snappyajaxfunction('/country/code/32', doSomething);

The closure allows 'request' to be available within the function that handles the onreadystatechange. The function 'fn' is passed as a parameter of snappyajaxfunction.