function creaAjax(){
	var objetoAjax=false;
	try {
		/*Para navegadores distintos a internet explorer*/
		objetoAjax = new ActiveXObject("Msxml2.XMLHTTP");
	} catch (e) {
		try {
			/*Para explorer*/
			objetoAjax = new ActiveXObject("Microsoft.XMLHTTP");
		} 
		catch (E) {
		objetoAjax = false;
		}
	}
	if (!objetoAjax && typeof XMLHttpRequest!='undefined') {
		objetoAjax = new XMLHttpRequest();
	}
	return objetoAjax;
}

function FAjax (url,capa,valores,metodo, modo)
{
   var ajax=creaAjax();
   var capaContenedora = document.getElementById(capa);
	/*instancia si el metodo elegido es POST*/
	 if(metodo.toUpperCase()=='POST'){
		document.write="instance right";
		ajax.open ('POST', url, true);
	    ajax.onreadystatechange = function() {
											if (ajax.readyState==1) {
												capaContenedora.innerHTML="<div style='text-align:center;'>Cargando.......</div>";
											}
											else if (ajax.readyState==4){
												if(ajax.status==200){
													document.getElementById(capa).innerHTML=ajax.responseText; 
													if(modo){
														onEditionMode();
													}
												}
												else if(ajax.status==404){
													capaContenedora.innerHTML = "La Url no existe";
												}
												else{
													capaContenedora.innerHTML = "Error: ".ajax.status;
												}
											}
										}
		ajax.setRequestHeader('Content-Type','application/x-www-form-urlencoded');
		ajax.send(valores);
		return;
	}
	/*instancia si el metodo elegido es GET*/
	if (metodo.toUpperCase()=='GET'){
	
		ajax.open ('GET', url, true);
		ajax.onreadystatechange = function() {
										if (ajax.readyState==1 || ajax.readyState==2 || ajax.readyState==3) {
										
											capaContenedora.innerHTML="<div style='text-align:center;'>Cargando.......</div>";
										}
										else if (ajax.readyState==4){
											if(ajax.status==200){ 
												document.getElementById(capa).innerHTML=ajax.responseText; 
												if(modo){
													onEditionMode();
												}
											}
											else if(ajax.status==404){
												capaContenedora.innerHTML = "La url no existe";
											}
											else{
												capaContenedora.innerHTML = "Error: ".ajax.status;
											}
										}
									}
		ajax.setRequestHeader('Content-Type','application/x-www-form-urlencoded');
		ajax.send(null);
		return
	}
}