Originariamente inviato da rollowin
il codice che mi hai postato non funziona, non mi fa ne il controllo ne mi apre la pagina random
avrai sbagliato qualcosaltro
ho appena fatto una prova
presumo che nel form ci siamo 25 gruppi di radio (o di checkbox)
codice:
<HTML>
<HEAD>
<script type="text/JavaScript">
function verifica() {
  ritorno = true;
  msg = "";
  for (var k=1;k<=25;k++) {
    c = document.domanda.elements["cred"+k];
    r = false;
    for (var i=0;i<c.length;i++) {r=(r||c[i].checked)};
    if (!r) msg+="devi ancora rispondere alla affermazione n° "+k+"\n"; 
    ritorno = ritorno&&r;
  }
  if (!ritorno) alert(msg);
  return ritorno;
}

sites = new Array()
sites [0] = "dom21.php"
sites [1] = "dom21b.php"
sites [2] = "dom21c.php"
sites [3] = "dom21d.php"
sites [4] = "dom21e.php"

</script>
</HEAD>
<BODY>
<FORM action="" method="post" NAME="domanda" id="domanda" onsubmit="if(verifica()){this.action=sites[parseInt(Math.random()*sites.length)];return true}else{return false}">

	1)1<input type="radio" name="cred1" value="1"> 2<input type="radio" name="cred1" value="2"> 3<input type="radio" name="cred1" value="3"> 

	2)1<input type="radio" name="cred2" value="1"> 2<input type="radio" name="cred2" value="2"> 3<input type="radio" name="cred2" value="3"> 

	3)1<input type="radio" name="cred3" value="1"> 2<input type="radio" name="cred3" value="2"> 3<input type="radio" name="cred3" value="3"> 

	4)1<input type="radio" name="cred4" value="1"> 2<input type="radio" name="cred4" value="2"> 3<input type="radio" name="cred4" value="3"> 

	5)1<input type="radio" name="cred5" value="1"> 2<input type="radio" name="cred5" value="2"> 3<input type="radio" name="cred5" value="3"> 

	6)1<input type="radio" name="cred6" value="1"> 2<input type="radio" name="cred6" value="2"> 3<input type="radio" name="cred6" value="3"> 

	7)1<input type="radio" name="cred7" value="1"> 2<input type="radio" name="cred7" value="2"> 3<input type="radio" name="cred7" value="3"> 

	8)1<input type="radio" name="cred8" value="1"> 2<input type="radio" name="cred8" value="2"> 3<input type="radio" name="cred8" value="3"> 

	9)1<input type="radio" name="cred9" value="1"> 2<input type="radio" name="cred9" value="2"> 3<input type="radio" name="cred9" value="3"> 

	10)1<input type="radio" name="cred10" value="1"> 2<input type="radio" name="cred10" value="2"> 3<input type="radio" name="cred10" value="3"> 

	11)1<input type="radio" name="cred11" value="1"> 2<input type="radio" name="cred11" value="2"> 3<input type="radio" name="cred11" value="3"> 

	12)1<input type="radio" name="cred12" value="1"> 2<input type="radio" name="cred12" value="2"> 3<input type="radio" name="cred12" value="3"> 

	13)1<input type="radio" name="cred13" value="1"> 2<input type="radio" name="cred13" value="2"> 3<input type="radio" name="cred13" value="3"> 

	14)1<input type="radio" name="cred14" value="1"> 2<input type="radio" name="cred14" value="2"> 3<input type="radio" name="cred14" value="3"> 

	15)1<input type="radio" name="cred15" value="1"> 2<input type="radio" name="cred15" value="2"> 3<input type="radio" name="cred15" value="3"> 

	16)1<input type="radio" name="cred16" value="1"> 2<input type="radio" name="cred16" value="2"> 3<input type="radio" name="cred16" value="3"> 

	17)1<input type="radio" name="cred17" value="1"> 2<input type="radio" name="cred17" value="2"> 3<input type="radio" name="cred17" value="3"> 

	18)1<input type="radio" name="cred18" value="1"> 2<input type="radio" name="cred18" value="2"> 3<input type="radio" name="cred18" value="3"> 

	19)1<input type="radio" name="cred19" value="1"> 2<input type="radio" name="cred19" value="2"> 3<input type="radio" name="cred19" value="3"> 

	20)1<input type="radio" name="cred20" value="1"> 2<input type="radio" name="cred20" value="2"> 3<input type="radio" name="cred20" value="3"> 

	21)1<input type="radio" name="cred21" value="1"> 2<input type="radio" name="cred21" value="2"> 3<input type="radio" name="cred21" value="3"> 

	22)1<input type="radio" name="cred22" value="1"> 2<input type="radio" name="cred22" value="2"> 3<input type="radio" name="cred22" value="3"> 

	23)1<input type="radio" name="cred23" value="1"> 2<input type="radio" name="cred23" value="2"> 3<input type="radio" name="cred23" value="3"> 

	24)1<input type="radio" name="cred24" value="1"> 2<input type="radio" name="cred24" value="2"> 3<input type="radio" name="cred24" value="3"> 

	25)1<input type="radio" name="cred25" value="1"> 2<input type="radio" name="cred25" value="2"> 3<input type="radio" name="cred25" value="3"> 

<input type="submit" value="sub" id=submit1 name=submit1>
</form>
</BODY>
</HTML>