function CheckDate(obj) {
	if(obj.value == "") {
		alert("Please input date range.");
		return false;
	}

	if(obj.value.length != 10){
		alert("From date length is invalid!");
		return false;
	}
	
	if (obj.value.substring(4,5) != "/" || obj.value.substring(7,8) != "/") {
	    alert ("The value of date range format is YYYY/MM/DD .");
	    return false;
	} 

	if(!isDateFormat(obj.value)){
	    return false;
	}
	
	return true;
}

function search_word(obj1, obj2) {
var i, s_leng;
var string;

	string = obj1.value.toUpperCase();
	s_leng = obj1.value.length;
	
	if (s_leng  == 0) return;

	for(i = 0; i < obj2.length; i++) {
		if (obj2.options[i].text.indexOf(string) == 0) {
			obj2.options[i].selected = true;
			break;
		} else {
			obj2.options[i].selected = false;
		}
	}
}

function chk_word(obj,type, version) {
	if (version == "ENG") {
		if (obj.value == "") {
			if (type == "port") {
				obj.value = "--- Type leading name of port ---";
			} else {
				obj.value = "--- Type leading name of vessel name ---";
			}
		}
	} else {
		if (obj.value == "") {
			obj.value = "--- ½Ð¿é¤J¬d¸ß¦r¦ê ---";
		}
	}		
}

function isDateFormat(sdate){
var strMonth = "";
var strYear = "";
var strDay = "";
var daysInMonth = DaysArray(12);

	strYear = sdate.substring(0,4);
	if(!isInteger(strYear)){
		alert("Year is invalid !");
		return false;
	}
	strMonth = sdate.substring(5,7);
	if (strMonth.charAt(0)=="0" && strMonth.length>1) 
		strMonth=strMonth.substring(1);
      
	if(!isInteger(strMonth)){
		alert("Month is invalid !");
		return false;
	}
	strDay = sdate.substring(8,10);
    if (strDay.charAt(0)=="0" && strDay.length>1) 
        strDay=strDay.substring(1);
       
	if(!isInteger(strDay)){
		alert("Day is invalid !");
		return false;
	}

	year = parseInt(strYear);
	month = parseInt(strMonth);
	day = parseInt(strDay);

	if (month < 1 || month > 12){
		alert("Please enter a valid month.");
		return false;
	}

	if (day < 1 || day > 31 || (month == 2 && day > daysInFebruary(year)) || day > daysInMonth[month]){
		alert("Please enter a valid day.");
		return false;
	}
       
	return true;
}

function isInteger(s){
var i;
    for (i = 0; i < s.length; i++){   
        var c = s.charAt(i);
        if (((c < "0") || (c > "9")))
           return false;
    }
    return true;
}
function daysInFebruary (year){
    return (((year % 4 == 0) && ( (!(year % 100 == 0)) || (year % 400 == 0))) ? 29 : 28 );
}
function DaysArray(n) {
   for (var i = 1; i <= n; i++) {
        this[i] = 31;
        if (i == 4 || i == 6 || i == 9 || i == 11) {
           this[i] = 30;
        }
        if (i == 2) {
           this[i] = 29;
       }
   } 
   return this;
}