function isdate(strDate){
  var strSeparator = "-";
  var strDateArray;
  var intYear;
  var intMonth;
  var intDay;
  var boolLeapYear;
  
  strDateArray = strDate.split(strSeparator);
  
  if(strDateArray.length!=3) return false;
  
  intYear = parseInt(strDateArray[0],10);
  intMonth = parseInt(strDateArray[1],10);
  intDay = parseInt(strDateArray[2],10);
  
  if(isNaN(intYear)||isNaN(intMonth)||isNaN(intDay)) return false;
  
  if(intMonth>12||intMonth<1) return false;
  
  if((intMonth==1||intMonth==3||intMonth==5||intMonth==7||intMonth==8||intMonth==10||intMonth==12)&&
(intDay>31||intDay<1)) return false;
  
  if((intMonth==4||intMonth==6||intMonth==9||intMonth==11)&&(intDay>30||intDay<1)) return false;
  
  if(intMonth==2){
      if(intDay<1) return false;
      
      boolLeapYear = false;
      if((intYear%100)==0){
        if((intYear%400)==0) boolLeapYear = true;
      }
      else{
        if((intYear%4)==0) boolLeapYear = true;
      }
      
      if(boolLeapYear){
        if(intDay>29) return false;
      }
      else{
        if(intDay>28) return false;
      }
  }
  
  return true;
}

function check_num()
{
   if (event.keyCode < 45 || event.keyCode > 57)
   event.returnValue = false;  
} 

function compareDate(strdate1,strdate2) {
  var strSeparator = "-"; 
  var strDateArray;
  var intYear;
  var intMonth;
  var intDay;
  var boolLeapYear;
  
  strDateArray = strdate1.split(strSeparator);
  
  if(strDateArray.length!=3) return false;
  
  intYear = parseInt(strDateArray[0],10);
  intMonth = parseInt(strDateArray[1],10);
  intDay = parseInt(strDateArray[2],10);
  
  date1 = new Date(intYear,intMonth,intDay);

  strDateArray = strdate2.split(strSeparator);
  
  if(strDateArray.length!=3) return false;
  
  intYear = parseInt(strDateArray[0],10);
  intMonth = parseInt(strDateArray[1],10);
  intDay = parseInt(strDateArray[2],10);
  
  date2 = new Date(intYear,intMonth,intDay);
  if (date1 > date2) return false;
  
  return true;
}

function verifyEmail(obj){ 
   var email = obj.value; 
   if(email == "") return true;
   var pattern = /^([a-zA-Z0-9_-])+@([a-zA-Z0-9_-])+(\.[a-zA-Z0-9_-])+/; 
   flag = pattern.test(email); 
   if(flag){
     return true;
   } else { 
     alert("Invalid Email Address!"); 
     return false;
   } 
} 

function replace(str,replace_what,replace_with)
{
	var ndx=str.indexOf(replace_what);
	var delta=replace_with.length - replace_what.length;
	while(ndx >= 0){
		str=str.substring(0,ndx)+replace_with+str.substring(ndx+replace_what.length);
		ndx=str.indexOf(replace_what,ndx+delta+1);
	}
	return str;
}