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 MostrarConsulta(datos){
        divResultado = document.getElementById('resultado');
        ajax=objetoAjax();

		var query_string = "entrada="+ encodeURIComponent(document.getElementById('entrada').value);


        ajax.open("POST", datos,true);
		
		ajax.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded;charset=ISO-8859-1');
		ajax.setRequestHeader("Content-length", query_string.length);
		ajax.setRequestHeader("Connection", "close");
		
        ajax.onreadystatechange=function() {
			
			    if (ajax.readyState==1) {
                        divResultado.innerHTML = '<div align="center"><img src="http://tiendasonline.eu/ajaxphp/loading.gif" align="\'center\'" /></div>' ;               }
                if (ajax.readyState==4) {
                        divResultado.innerHTML = ajax.responseText;
                }
        }
        ajax.send(query_string);
}