function trim(inputString) {
   // Removes leading and trailing spaces from the passed string. Also removes
   // consecutive spaces and replaces it with one space. If something besides
   // a string is passed in (null, custom object, etc.) then return the input.
   if (typeof inputString != "string") { return inputString; }
   var retValue = inputString;
   var ch = retValue.substring(0, 1);
   while (ch == " ") { // Check for spaces at the beginning of the string
      retValue = retValue.substring(1, retValue.length);
      ch = retValue.substring(0, 1);
   }
   ch = retValue.substring(retValue.length-1, retValue.length);
   while (ch == " ") { // Check for spaces at the end of the string
      retValue = retValue.substring(0, retValue.length-1);
      ch = retValue.substring(retValue.length-1, retValue.length);
   }
   while (retValue.indexOf("  ") != -1) { // Note that there are two spaces in the string - look for multiple spaces within the string
      retValue = retValue.substring(0, retValue.indexOf("  ")) + retValue.substring(retValue.indexOf("  ")+1, retValue.length); // Again, there are two spaces in each of the strings
   }
   return retValue; // Return the trimmed string back to the user
}



function valid(){
	var nick = document.dati.innick.value;
	var pass = document.dati.inpass.value;
	var pass2 = document.dati.inpass2.value;
	var nk = trim(nick);
	var ps = trim(pass);
	if(nk==""||nk==null) alert("Il nickname è obbligatorio!!! Prego inserirlo!");
	else if(ps==""||ps==null) alert("La password è obbligatoria!!! Prego inserirla!");
	else if(pass==pass2) document.dati.submit();
	else alert("Le password non coincidono! Prego controllarle!");
}