<select name="pais_l" onchange="makeRequest('comboEstado','../inc/arrest.php?pa='+this.value);">
function makeRequest(campo,url){
http_request = false;
if(window.XMLHttpRequest){ // mozilla, netscape, opera...
http_request = new XMLHttpRequest();
if(http_request.overrideMimeType){
http_request.overrideMimeType('text/xml');
}
}else if(window.ActiveXObject){ // IE
try{
http_request = new ActiveXObject("Msxml2.XMLHTTP");
}catch(e){
try{
http_request = new ActiveXObject("Microsoft.XMLHTTP");
}catch(e){
}
}
}
if(!http_request){
alert('Falla :( No es posible crear una instancia XMLHTTP');
return false;
}
if(campo == 'comboEstado')
http_request.onreadystatechange = comboEstado;
if(campo == 'comboEstado1')
http_request.onreadystatechange = comboEstado1;
http_request.open('GET', url, true);
http_request.send(null);
}
function comboEstado(){
if(http_request.readyState == 4){
if(http_request.status == 200){
var opciones=http_request.responseText.split('|');
document.forms.form1.estado_l.options.length=0;
for(var i=0; i<opciones.length; i++){
var par=opciones[i].split('#');
document.forms.form1.estado_l.options[i]=new Option(par[1],par[0]);
}
document.forms.form1.estado_l.options.length--;
}else{
alert('Hubo problemas con la petición.');
}
}
}