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Simple HTML calendar feed from Users Free/Busy data

A while ago I posted this about creating a simple html calendar like the ones you see in OWA. I was looking though some OWA captures today and noticed the following command is called when you manipulate the calender object in OWA.

?Cmd=monthfreebusy&start=2004-07-25T00:00:00+10:00&end=2004-09-05T00:00:00+10:00

(the +10:00 at the end I believe refers to the time zone offset which you need to adjust to your own timezone or put some code in that does it)

What this does is return a single string of numbers with each day in-between the &start and &end variables represented by a 0 if there are no appointments that day, a 1 if there is and a 2 is no freebusy data has been published.

I took this function and combined it with some WebDAV in a ASP page and was able to feed the simple html calendar and make it bold all the dates in the calendar that there where appointments on, I also created a few functions so you could change months back and forth.

The limitations of this method is that it only works for the months where free-busy information has been published and it doesn't work for public folder calendars because no free busy information is maintained for these. It should however come in handy for things like resource mailboxes where having a simple calendar comes in handy.

I've posted up a copy of the ASP page and button images here http://msgdev.mvps.org/exdevblog/showcalendar.zip (don't forget to change the timezone unless you live on the East coast of Aus)

The code itself look like


<table border="0" id="table1" cellpadding="2" width="147">
<tr><b>
<%
sdate = request.querystring("sdate")
if sdate = "" then
wdate = now()
mmonth = monthname(month(now())) & " " & Year(now())
else
wdate = dateserial(mid(sdate,1,4),mid(sdate,6,2),mid(sdate,9,2))
mmonth = monthname(month(wdate)) & " " & Year(wdate)
end if
pmonth = condate(dateadd("m",-1,wdate))
stime = condate(wdate)
etime = condate(dateadd("m",1,wdate))
response.write "<td style=""padding: 0"" width=""147"" align=""center"" colspan=""7""><b><font
face=""Arial Narrow"" size=2 color=""#000080"">"
response.write "<a href=""showcalendar.asp?sdate=" & etime & """><img
border=""0"" src=""pg-next.gif"" width=""16"" height=""16""
align=""right""></a>"
response.write "<a href=""showcalendar.asp?sdate=" & pmonth & """><img
border=""0"" src=""pg-prev.gif"" width=""16"" height=""16""
align=""left""></a><B>" & mmonth & "</b></td>"
%>
</font></b> </tr>
<tr>
<td style="border-bottom-style: solid; padding: 0" width="16" align="center">
M</td>
<td style="border-bottom-style: solid; padding: 0" width="16" align="center">
T</td>
<td style="border-bottom-style: solid; padding: 0" width="16" align="center">
W</td>
<td style="border-bottom-style: solid; padding: 0" width="16" align="center">
T</td>
<td style="border-bottom-style: solid; padding: 0" width="16" align="center">
F</td>
<td style="border-bottom-style: solid; padding: 0" width="16" align="center">
S</td>
<td style="border-bottom-style: solid; padding: 0" width="16" align="center">
S</td>
</tr>
<%

urlstr = "http://servername/exchange/mailbox/calendar/?Cmd=monthfreebusy&start="
& stime & "T00:00:00+10:00&end=" & etime & "T00:00:00+10:00"
Set Objxml = Server.CreateObject("Microsoft.XMLhttp")
Objxml.Open "Get", urlstr, False, "", ""
Objxml.setRequestHeader "Accept-Language:", "en-us"
Objxml.setRequestHeader "Content-type:", "application/x-www-UTF8-encoded"
Objxml.setRequestHeader "Content-Length:", Len(szXml)
Objxml.Send szXml
set oResponseDoc = Objxml.responseXML
set oNodeList = oResponseDoc.getElementsByTagName("fbdata")
For i = 0 To (oNodeList.length -1)
set oNode = oNodeList.nextNode
caldata = oNode.text
next
cdatefday = cdate(dateserial(year(wdate),month(wdate),"1"))
sday = weekday(cdatefday,2)
cmonth = month(wdate)
for x = 1 to 6
response.write "<tr>"
for i = 1 to 7
if cmonth = month(cdatefday) then
if sday =< i then
sday = 0
if mid(caldata,day(cdatefday),1) = 1 then
response.write "<td style=""padding: 0"" width=""16"" align=""center""><b>" &
day(cdatefday) & "</b></td>"
else
response.write "<td style=""padding: 0"" width=""16"" align=""center"">" &
day(cdatefday) & "</td>"
end if
cdatefday = dateadd("d",1,cdatefday)
else
response.write "<td style=""padding: 0"" width=""16"" align=""center""> </td>"

end if
else
response.write "<td style=""padding: 0"" width=""16"" align=""center""> </td>"

end if
next
response.write "</tr>"
next


function condate(date2con)
dtcon = date2con
if month(dtcon) < 10 then
if day(dtcon) < 10 then
qdat = year(dtcon) & "-" & "0" & month(dtcon) & "-" & "01"
else
qdat = year(dtcon) & "-" & "0" & month(dtcon) & "-" & "01"
end if
else
if day(dtcon) < 10 then
qdat = year(dtcon) & "-" & month(dtcon) & "-" & "01"
else
qdat = year(dtcon) & "-" & month(dtcon) & "-" & "01"
end if
end if
condate = qdat
end function
%>

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All sample scripts and source code is provided by for illustrative purposes only. All examples are untested in different environments and therefore, I cannot guarantee or imply reliability, serviceability, or function of these programs.

All code contained herein is provided to you "AS IS" without any warranties of any kind. The implied warranties of non-infringement, merchantability and fitness for a particular purpose are expressly disclaimed.