/*****************************************************/
function ajaxFunction() {
  var xmlHttp;
  try {
    xmlHttp=new XMLHttpRequest();
    return xmlHttp;
  } catch (e) {
    
    try {
      xmlHttp=new ActiveXObject("Msxml2.XMLHTTP");
      return xmlHttp;
    } catch (e) {
      
      try {
        xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");
        return xmlHttp;
      } catch (e) {
        alert("Tu navegador no soporta AJAX!");
        return false;
      }}}
}
 
function Carga(_pagina,capa) {
    var ajax;
    ajax = ajaxFunction();
    ajax.open("POST", _pagina, true);
    ajax.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
    ajax.onreadystatechange = function() {
        if (ajax.readyState==1){
            document.getElementById(capa).innerHTML = " Cargando...";
                 }
        if (ajax.readyState == 4) {
                document.getElementById(capa).innerHTML=ajax.responseText; 
             }}
     ajax.send(null);
}