function 

loadScript(url, callback){ 

    

var 

script = document.createElement(

"script"

) 

    

script.type = 

"text/javascript"

; 

    

if 

(script.readyState){ 

//IE 

        

script.onreadystatechange = 

function

(){ 

            

if 

(script.readyState == 

"loaded" 

|| script.readyState == 

"complete"

){ 

                

script.onreadystatechange = 

null

; 

                

callback(); 

            

}}; 

    

}

else

{

        

//Others: Firefox, Safari, Chrome, and Opera 

        

script.onload = 

function

(){ 

            

callback(); 

        

}; 

    

} 

    

script.src = url; 

    

document.body.appendChild(script); 

}