function changeLangDropdown(lang){
	url = window.location.href;
	
	if(url.search("/en") != -1){
		url = url.replace("/en", "/th");
	}else if(url.search("/th") != -1){
		url = url.replace("/th", "/en");
	}else{
		if(document.getElementById("homepage") == "en"){
			url = url+"th";	
		}else{
			url = url+"en";	
		}
	}
	
	location = url; 
}