var myString = new String(document.location);
var lang = myString.slice(myString.lastIndexOf(".php")-2,(myString.lastIndexOf(".php")));

function switch_language(){
	if (lang == "fr"){
		var debut = myString.slice(0,myString.lastIndexOf(".php")-2)
		var fin = myString.slice((myString.lastIndexOf(".php")),myString.length);
		
		document.location = debut + "en" + fin;
	}
	
	if (lang == "en"){
		var debut = myString.slice(0,myString.lastIndexOf(".php")-2)
		var fin = myString.slice((myString.lastIndexOf(".php")),myString.length);
		
		document.location = debut + "fr" + fin;
	}
}