Stuff

function dobcheck(){
	var dob = document.input.dob.value;
	var reg1 = /^(0[1-9]|[12][0-9]|3[01])[\- \/\.](0[1-9]|1[012])[\- \/\.](19|20)\d\d$/;
	var out1 = "ouch";
	
	if ( ! reg1.test(dob)){
		 out1 = "Not a date format";
	}
	else {
		var dd = dob.substring(0,2);
		var mm = dob.substring(3,5);
		var yyyy = dob.substring(6,10);
		
		var ok = "Good, " + dd + "/" + mm + "/" + yyyy + " is a real date";
		
		if ( dd == "31"){
			if ( mm == "02" || mm == "04" || mm == "06" || mm == "09" || mm == "11"){
				out1 = "There are not 31 days in the month " + mm;
			}
			else{
				out1 = ok;
			}
		}
		else if ( mm == "02") {
			var month = "Feb";
			
			if (dd == "30"){
				out1 = "There are not 30 days in the month " + month;
			}
			else if ( dd == "29"){
				if ( (yyyy%4) != 0){
					out1 = "This is not a leap year.";
				}
				else if ( ((yyyy%100) == 0)) && ((yyyy%1000) != 0)){
					out1 = "This is not a leap year, it really isn't";
				}
				else {
					out1 = ok;
				}
			}
			else {
				out1 = ok;
			}
		}
		else {
			out1 = ok;
		}
	}
	
	
	
	
	return dob_error.innerHTML = out1;
}