How can I insert a value to configure Ajax function upon clicking on link?

[mike]

I'm trying to set a function that makes an Ajax call, but I must confess I can't understand what's happening when I set the onclick event. I'm trying to make an Ajax call to get fields from a database and display them to the user. The idea is that the users type a Last Name in an input field, and then, depending on the link they click on, the function I'm trying to build displays the results of a query to the database. I handle the query with a switch statement in PHP on the script that the Ajax function calls, but I can't set the variable that handles this behavior on the Javascript code. I've got the Javascript code like this: \[code\]var ajaxRequest = ajaxFunction();function ajaxFunction(){var ajaxRequest; // The variable that makes Ajax possible!try{ // Opera 8.0+, Firefox, Safari ajaxRequest = new XMLHttpRequest();} catch (e){ // Internet Explorer Browsers try{ ajaxRequest = new ActiveXObject("Msxml2.XMLHTTP"); } catch (e) { try{ ajaxRequest = new ActiveXObject("Microsoft.XMLHTTP"); } catch (e){ // Something went wrong alert("Your browser broke!"); return false; } }} return ajaxRequest;} function process() {id="default";profesional = document.getElementById('profesional');dotal = document.getElementById('dot'); proyecta = document.getElementById('proy');proyecta_A = document.getElementById('proy_af');gastosM = document.getElementById('gastos_med');autos = document.getElementById('aut');polifam = document.getElementById('polif');profesional.onclick=function() {id="prof";return id; }dotal.onclick=function() {id="dotal";return id; }proyecta.onclick=function() {id="proyecta"; return id;}proyecta_A.onclick=function() {id="proyAf";return id; }gastosM.onclick=function() {id="gastos_medicos";return id; }autos.onclick=function() {id="autos"; return id;}polifam.onclick=function() {id="polifam";return id; } if(ajaxRequest.readyState==4 || ajaxRequest.readyState==0) {apellido = encodeURIComponent(document.getElementById('query').value)if (apellido != undefined) {ajaxRequest.open("GET", 'adminsrc.php?buscarregistro=' +apellido +'&id='+id, true)ajaxRequest.send(""); ajaxRequest.onreadystatechange=handleServerResponse;}}else setTimeout('process()',1000);}function handleServerResponse(){{if (ajaxRequest.readyState==4) {if(ajaxRequest.status==200) { respuesta=ajaxRequest.responseXML;respuestadoc = respuesta.documentElement;if (apellido != undefined) {ident = respuesta.getElementsByTagName('identidad')[0];result = ident.firstChild;refrescar = respuesta.getElementsByTagName('identidad')[1];actualizar = refrescar.firstChild;if(result!=undefined) {resultado = result.data;document.getElementById('profesreg').setAttribute('value', resultado);document.getElementById('dotalreg').setAttribute('value', resultado);document.getElementById('gmmreg').setAttribute('value', resultado);document.getElementById('proyectareg').setAttribute('value', resultado);document.getElementById('proyecta2reg').setAttribute('value', resultado);document.getElementById('autosreg').setAttribute('value', resultado);document.getElementById('polifreg').setAttribute('value', resultado);}if(actualizar!=undefined) {actualiza = actualizar.data;document.getElementById('actual_1').setAttribute('value', actualiza);document.getElementById('actual_2').setAttribute('value', actualiza);document.getElementById('actual_3').setAttribute('value', actualiza);document.getElementById('actual_4').setAttribute('value', actualiza);document.getElementById('actual_5').setAttribute('value', actualiza);document.getElementById('actual_6').setAttribute('value', actualiza);document.getElementById('actual_7').setAttribute('value', actualiza);}msje = respuestadoc.firstChild.childNodes[0]; if (msje !=undefined) {mess = msje.data;document.getElementById("res").innerHTML = "<h4>"+ mess +"</h4>";} } setTimeout('process()',1000); } else alert ('hubo un problema al conectarse con el servidor: ' + ajaxRequest.statusText);}}} //-->\[/code\]Where the last part is just to set the value of hidden fields in the form so that PHP recognizes those values (they are set to update some fields in the database). But I must say I'm pretty stuck with the javascript (I've never been good at it). Any suggestions, please?