<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()"/>