var dtCh= "/";
var minYear=1900;
var maxYear=2100;

function isInteger(s){
	var i;
    for (i = 0; i < s.length; i++){   
        // Check that current character is number.
        var c = s.charAt(i);
        if (((c < "0") || (c > "9"))) return false;
    }
    // All characters are numbers.
    return true;
}

function stripCharsInBag(s, bag){
	var i;
    var returnString = "";
    // Search through string's characters one by one.
    // If character is not in bag, append to returnString.
    for (i = 0; i < s.length; i++){   
        var c = s.charAt(i);
        if (bag.indexOf(c) == -1) returnString += c;
    }
    return returnString;
}

function daysInFebruary (year){
	// February has 29 days in any year evenly divisible by four,
    // EXCEPT for centurial years which are not also divisible by 400.
    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
}

// ******************************************************************

function CheckDate(dateStr) {

var datePat = /^(\d{1,2})(\/|-)(\d{1,2})(\/|-)(\d{4})$/;
var matchArray = dateStr.match(datePat); // is the format ok?

if (matchArray == null) {
alert("Please enter date as either mm/dd/yyyy or mm-dd-yyyy.");
return false;
}

month = matchArray[1]; // p@rse date into variables
day = matchArray[3];
year = matchArray[5];

if (month < 1 || month > 12) { // check month range
alert("Month must be between 1 and 12.");
return false;
}

if (day < 1 || day > 31) {
alert("Day must be between 1 and 31.");
return false;
}

if ((month==4 || month==6 || month==9 || month==11) && day==31) {
alert("Month "+month+" doesn`t have 31 days!")
return false;
}

if (month == 2) { // check for february 29th
var isleap = (year % 4 == 0 && (year % 100 != 0 || year % 400 == 0));
if (day > 29 || (day==29 && !isleap)) {
alert("February " + year + " doesn`t have " + day + " days!");
return false;
}
}

if (year < 1940 || year >= 2100) {
	alert("Invalid year");
	return false;
}

return true; // date is valid
}


function isDate(dtStr,iFormat){


	var daysInMonth = DaysArray(12)
	var pos1=dtStr.indexOf(dtCh)
	var pos2=dtStr.indexOf(dtCh,pos1+1)
/*Interchange the variables strMonth to strDay will effect like dd/mm/yyyy*/
	if (iFormat == "1"){
		var strMonth=dtStr.substring(0,pos1)
		var strDay=dtStr.substring(pos1+1,pos2)
	}else{
		var strDay=dtStr.substring(0,pos1)
		var strMonth=dtStr.substring(pos1+1,pos2)
	}
	var strYear=dtStr.substring(pos2+1)
	strYr=strYear
	if (strDay.charAt(0)=="0" && strDay.length>1) strDay=strDay.substring(1)
	if (strMonth.charAt(0)=="0" && strMonth.length>1) strMonth=strMonth.substring(1)
	for (var i = 1; i <= 3; i++) {
		if (strYr.charAt(0)=="0" && strYr.length>1) strYr=strYr.substring(1)
	}
	month=parseInt(strMonth)
	day=parseInt(strDay)
	year=parseInt(strYr)
	if (pos1==-1 || pos2==-1){
		alert("The date format should be : mm/dd/yyyy")
		return false
	}
	if (strMonth.length<1 || month<1 || month>12){
		alert("Please enter a valid month")
		return false
	}
	if (strDay.length<1 || day<1 || day>31 || (month==2 && day>daysInFebruary(year)) || day > daysInMonth[month]){
		alert("Please enter a valid day")
		return false
	}
	if (strYear.length != 4 || year==0 || year<minYear || year>maxYear){
		alert("Please enter a valid 4 digit year between "+minYear+" and "+maxYear)
		return false
	}
	if (dtStr.indexOf(dtCh,pos2+1)!=-1 || isInteger(stripCharsInBag(dtStr, dtCh))==false){
		alert("Please enter a valid date")
		return false
	}
return true
}

function ValidateForm(idate, DateFormat){
	var dt=idate

	if (isDate(dt.value, DateFormat)==false){
		dt.focus()
		return false
//	}else{
//		alert("no man")
//		return false
	}
    return true
 }