<script type="text/javascript" language="javascript">

function ValidateDate()

{

var SDate = document.getElementById('txtStartDate').value;

var EDate = document.getElementById('txtEndDate').value;

var alertReason1 = 'End Date must be greater than or equal to Start Date.';

var alertReason2 = 'End Date can not be less than Current Date.';

var endDate = new Date(EDate);

var startDate= new Date(SDate);

if(SDate != '' && EDate != '' && startDate > endDate)

{

alert(alertReason1);

//document.getElementById('txtEndDate').value = "";

return false;

}

else if(SDate == '')

{

alert("Please enter Start Date");

return false;

}

else if(EDate == '')

{

alert("Please enter End Date");

return false;

}

return true;

}

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 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){

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 ValidateDate(obj){

if (isDate(obj.value)==false){

var CurrentDate = new Date();

obj.value = CurrentDate.getMonth() + 1 + "/" + CurrentDate.getDate() + "/" + CurrentDate.getFullYear()

//dt.focus()

return false;

}

return true

}

</script>

<asp:TextBox ID="txtStartDate" runat="server" Width="80px" onblur="ValidateDate(this)"></asp:TextBox>

<asp:TextBox ID="txtEndDate" runat="server" Width="80px" onblur="ValidateDate(this)"></asp:TextBox>

<asp:Button ID="btnShowReport" runat="server" Text="Show Report" OnClick="btnShowReport_Click" OnClientClick="return ValidateDate()"/>