function isEmpty(objInput) {
	if (objInput == null || objInput == "") {
		return true
	}
	return false
}

function isEmailAddress (string) {
  var addressPattern = 
    /^\w+((-\w+)|(\.\w+))*\@[A-Za-z0-9]+((\.|-)[A-Za-z0-9]+)*\.[A-Za-z0-9]+$/;
  return addressPattern.test(string);
}


function isNum (argvalue) {
	argvalue = argvalue.toString();
	if (!argvalue.length) return false;
	for (var n=0; n<argvalue.length; n++)
		if (argvalue.substring(n, n+1) < "0" || argvalue.substring(n, n+1) > "9")
			return false;
	return true;
}


function isFloat (string) {
  var pattern = 
    /^(\+?((([0-9]+(\.)?)|([0-9]*\.[0-9]+))([eE][+-]?[0-9]+)?))$/;
  return pattern.test(string);
}


function isMobile (string) {
  var addressPattern = 
    /^06(-{0,1})[1-9][0-9]{7}$/;
  return addressPattern.test(string);
}


function isTelefoon (string) {
  var addressPattern = 
    /^0[1-9][0-9]{1,2}(-{0,1})[1-9][0-9]{5,6}$/;
  return addressPattern.test(string);
}


function isTel (string){
	if(string.length!=10) return false;
	return isTelefoon(string) || isMobile(string);
}


function isPostcode (string) {
	if(isPostcodeBE(string) || isPostcodeNL(string)) return true;
	return false;
}


function isPostcodeBE (string) {
	if(!isNum(string)) return false;
	if(string>999 && string<10000) return true;
	return false;
}


function isPostcodeNL (string) {
    var addressPattern = 
      /^[1-9][0-9]{3}[A-Za-z]{2}$/;
    return addressPattern.test(string);
}


function valiDate(day,month,year){
	if(!isNum(day)||!isNum(month)||!isNum(year)) return false;
	if ((month < 1 || month > 12) || (day < 1 || day > 31)) return false;
	if ((month==4 || month==6 || month==9 || month==11) && day==31) return false;
	if (month == 2) {
		var isleap = (year % 4 == 0 && (year % 100 != 0 || year % 400 == 0)); 
		if (day>29 || (day==29 && !isleap)) return false;
	} 
	if(year<1850 || year>2050)  return false;
	return true;
}