﻿// JScript File
var dtCh= "/";
var minYear=1900;
var maxYear=2100;

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 stripCharsInBag(s, bag)
{
	var i;
    var 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 isDate(dtStr)
{
	var daysInMonth = DaysArray(12);
	var pos1=dtStr.indexOf(dtCh);
	var pos2=dtStr.indexOf(dtCh,pos1+1);
	var strMonth=dtStr.substring(0,pos1);
	var strDay=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){return false;}
	
	if (strMonth.length<1 || month<1 || month>12){return false;	}
	
	if (strDay.length<1 || day<1 || day>31 || (month==2 && day>daysInFebruary(year)) || day > daysInMonth[month]){return false;}
	
	if (strYear.length != 4 || year==0 || year<minYear || year>maxYear)	{return false;}
	
	if (dtStr.indexOf(dtCh,pos2+1)!=-1 || isInteger(stripCharsInBag(dtStr, dtCh))==false){return false;}
    
    return true;
}


function ValidateForm()
{
	var dt=document.frmSample.txtDate;
	if (isDate(dt.value)==false)	{return false;}
    return true
 }

