function focusoncat(txt) { 
var str=document.getElementById('id_cat').value;
var str_s1='Sélectionner';
var str_s2='Select';
var str_s3='Sélectionner';
var str_s4='Selectionner';
document.getElementById('id_cat').value = str.replace(str_s1, "");
document.getElementById('id_cat').value = str.replace(str_s2, "");
document.getElementById('id_cat').value = str.replace(str_s3, "");
var patt=new RegExp(txt);
if(patt.exec(str)==txt){document.getElementById('id_cat').value = str.replace(txt+', ', ""); }
else{document.getElementById('id_cat').value += txt+', ' ; }
} 

function cachediv(iddiv){
	document.getElementById(iddiv).style.display = "none";
	/*document.getElementById('id_cat').style.value = "";*/
	document.getElementById('ct').style.display = "none";
}
function cachealldivs(){document.getElementById('ct').style.display = "none";document.getElementById('tabcat_acheter').style.display = "none";document.getElementById('tabcat_louer').style.display = "none";document.getElementById('tabcat_vacances').style.display = "none";constructions_ct();}

function videcat(){
var cbs1 = document.forms[0].elements['c_acheter'];
var cbs2 = document.forms[0].elements['c_louer'];
var cbs3 = document.forms[0].elements['c_louervacances'];
for(var i=0; i<cbs1.length; i++){cbs1[i].checked = false;}
for(var e=0; e<cbs2.length; e++){cbs2[e].checked = false;}
for(var r=0; r<cbs3.length; r++){cbs3[r].checked = false;}	
document.getElementById('id_cat').value = '';
document.getElementById('reqtypeFINI').value = '';
/*alert(document.getElementById('reqtypeFINI').value);*/
}
function affichdiv_tb(vide) {
if (document.getElementById('acheter').checked) {
	document.getElementById('tabcat_acheter').style.display = "";document.getElementById('ct').style.display = "";} 
	else {
	document.getElementById('tabcat_acheter').style.display = "none";}
if (document.getElementById('louer').checked) {
	document.getElementById('tabcat_louer').style.display = "";document.getElementById('ct').style.display = "";} 
	else {
	document.getElementById('tabcat_louer').style.display = "none";}
if (document.getElementById('vacances').checked) {
	document.getElementById('tabcat_vacances').style.display = "";document.getElementById('ct').style.display = "";} 
	else {
	document.getElementById('tabcat_vacances').style.display = "none";}
	if(vide=='1'){videcat();}
}

<!-- Begin
redirTime = "6000";
function redirTimer(iddiv) { setTimeout(cachediv(iddiv),redirTime); }
//  End -->

function constructions_ct() {
var listdescats='';var listdescats1='';var listdescats2='';var listdescats3='';
var cbs1 = document.forms[0].elements['c_acheter'];
var cbs2 = document.forms[0].elements['c_louer'];
var cbs3 = document.forms[0].elements['c_louervacances'];
for(var i=0; i<cbs1.length; i++){if(cbs1[i].checked){listdescats1 += cbs1[i].value;}}
for(var e=0; e<cbs2.length; e++){if(cbs2[e].checked){listdescats2 += cbs2[e].value;}}
for(var r=0; r<cbs3.length; r++){if(cbs3[r].checked){listdescats3 += cbs3[r].value;}}	
listdescats = listdescats1+listdescats2+listdescats3;
listdescats = listdescats.replace('undefined', '');listdescats = listdescats.replace('undefinedundefined', '');
listdescats = listdescats.replace('NaN', '');listdescats = listdescats.replace('undefined undefined', '');
/*alert(listdescats);*/
document.getElementById('reqtypeFINI').value  = "(1=0 "+listdescats+")";
//alert (document.getElementById('reqtypeFINI').value);

}