function keytest (check, condition) {
  if (check==condition) {
    event.returnValue = false;
  }
}

function colorspopup(itemname) {
	var popupleft = (window.screen.width - 305) / 2;
	var popuptop =  (window.screen.height - 100) / 2;
	window.open("selcolor.html','colors','toolbar=no,location=no,directories=no,status=no,menubar=no,scrollbars=no,resizable=no,width=305,height=100,top='+popuptop+',left='+popupleft");
}

function length_guard(area, max) {
	if (area.value.length > max) {
		area.value = area.value.substr(0, max);
	}
}

function getanswer(question) {
  if (confirm(question)){
  	return true ;
  }else{
  	return false ;
  }
}

function check_date(field){ // this opgeven als object
  var checkstr = "0123456789";
  var DateField = field;
  var Datevalue = "";
  var DateTemp = "";
  var seperator = "-";
  var day;
  var month;
  var year;
  var leap = 0;
  var err = 0;
  var i;
   err = 0;
   DateValue = DateField.value;
   /* Delete all chars except 0..9 */
   for (i = 0; i < DateValue.length; i++) {
	  if (checkstr.indexOf(DateValue.substr(i,1)) >= 0) {
	     DateTemp = DateTemp + DateValue.substr(i,1);
	  }
   }
   DateValue = DateTemp;
   /* Always change date to 8 digits - string*/
   /* if year is entered as 2-digit / always assume 20xx */
   if (DateValue.length == 6) {
      DateValue = DateValue.substr(0,4) + '20' + DateValue.substr(4,2); }
   if (DateValue.length != 8) {
      err = 19;}
   /* year is wrong if year = 0000 */
   year = DateValue.substr(4,4);
   if (year == 0) {
      err = 20;
   }
   /* Validation of month*/
   month = DateValue.substr(2,2);
   if ((month < 1) || (month > 12)) {
      err = 21;
   }
   /* Validation of day*/
   day = DateValue.substr(0,2);
   if (day < 1) {
     err = 22;
   }
   /* Validation leap-year / february / day */
   if ((year % 4 == 0) || (year % 100 == 0) || (year % 400 == 0)) {
      leap = 1;
   }
   if ((month == 2) && (leap == 1) && (day > 29)) {
      err = 23;
   }
   if ((month == 2) && (leap != 1) && (day > 28)) {
      err = 24;
   }
   /* Validation of other months */
   if ((day > 31) && ((month == "01") || (month == "03") || (month == "05") || (month == "07") || (month == "08") || (month == "10") || (month == "12"))) {
      err = 25;
   }
   if ((day > 30) && ((month == "04") || (month == "06") || (month == "09") || (month == "11"))) {
      err = 26;
   }
   /* if 00 ist entered, no error, deleting the entry */
   if ((day == 0) && (month == 0) && (year == 00)) {
      err = 0; day = ""; month = ""; year = ""; seperator = "";
   }
   /* if no error, write the completed date to Input-Field (e.g. 13.12.2001) */
   if (err == 0) {
      DateField.value = day + seperator + month + seperator + year;
   }
   /* Error-message if err != 0 */
   else {
      alert("Vul een geldige datum in het formaat dd-mm-yy in");
  	  DateField.focus();
   }
}