var send_form_cfg={
  url: '',
  onReadyState: null,
  divResult: '',
  formId: ''
}


function objetoAjax()
{
	var xmlhttp=false;
	try {
	  xmlhttp = new ActiveXObject("Msxml2.XMLHTTP");
	} catch (e) {
		try {
		  xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
		} catch (E) {
		  xmlhttp = false;
  		}
	}
	
	if (!xmlhttp && typeof XMLHttpRequest!='undefined') 
	{
		xmlhttp = new XMLHttpRequest();
	}
	return xmlhttp;
}



function ajaxEnviarFormulario(json_cfg)
{

var params = '';
var name='';
var value='';
var req = objetoAjax();

var f = document.getElementById( json_cfg.formId );
if(!f)
 return false;
 
 var i=0;
 for( i=0; i<f.elements.length; i++)
 {
    name = f.elements[i].name;
	value =  f.elements[i].value;
	params += name + "=" + encodeURI(value);
	
	if( i<f.elements.length-1  )
       params +=  '&';   
 }

 
req.onreadystate = function()
{
        if( json_cfg.divResult !='' )
		{
	         var e = document.getElementById( json_cfg.divResult );
		     if(e) 			 
			    e.innerHTML = req.responseText;
			else
			  alert("Formulario enviado.");
		}else{
		   alert("Enviado.");
		}
}

if( json_cfg.onReadyState != null ){
    req.onreadystate = json_cfg.onReadyState
}	 
   
   req.open('POST', json_cfg.url, true); 
   req.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded; charset=ISO-8859-1');         
   req.send(params);   
}