Formatting Dates in Classic ASP

During my internship at RPM, we used classic ASP for server side scripting rather than the PHP I’m more used to. Classic ASP is missing functions for formatting dates, like PHP and *NIX shell have, for instance. SQL Server has the CONVERT function, but only has a limited number of output formats, at least for the older SQL Server version we had: Otherwise, it would be more efficient to format the data as it is coming from the database . I built two functions for date formatting based on the PHP and *NIX “date” formats for use on the HSGA site, where I had to format dates a certain way for a project. I don’t remember if I used it on other projects, but I think so.

Both functions take two parameters. The first is a date, as would come from a SQL Server “datetime” field. The second is a string that defines the output format. The first function uses a format string like the php date function. The long function is as follows (tabs are double spaces due to the width and length of the content):

Function PHPFormatDateTime(strDateTime, strFormatString)
    Dim intI, strOutput, strTemp, bolEscape
    bolEscape = 0

    For intI = 1 to Len(strFormatString)
        If bolEscape = 0 then
            Select Case Mid(strFormatString, intI, 1)
                ' day
                Case "d"
                    If DatePart("d", strDateTime) < 10 Then
                        strOutput = strOutput & "0" & DatePart("d", strDateTime)  
                    Else
                        strOutput = strOutput & DatePart("d", strDateTime)
                    End If
                Case "j"
                    strOutput = strOutput & DatePart("d", strDateTime)
                Case "D"
                    Select Case DatePart("w", strDateTime)
                        Case 1
                            strOutput = strOutput &  "Mon"
                        Case 2
                            strOutput = strOutput &  "Tue"
                        Case 3
                            strOutput = strOutput &  "Wed"
                        Case 4
                            strOutput = strOutput &  "Thu"
                        Case 5
                            strOutput = strOutput &  "Fri"
                        Case 6
                            strOutput = strOutput &  "Sat"
                        Case 7
                            strOutput = strOutput &  "Sun"
                    End Select
                Case "l"
                    Select Case DatePart("w", strDateTime)
                        Case 1
                            strOutput = strOutput &  "Monday"
                        Case 2
                            strOutput = strOutput &  "Tuesday"
                        Case 3
                            strOutput = strOutput &  "Wednesday"
                        Case 4
                            strOutput = strOutput &  "Thursday"
                        Case 5
                            strOutput = strOutput &  "Friday"
                        Case 6
                            strOutput = strOutput &  "Saturday"
                        Case 7
                            strOutput = strOutput &  "Sunday"
                    End Select
                Case "S"
                    strTemp = DatePart("d", strDateTime)
                    If strTemp < 10 Then
                        strTemp = "0" & strTemp
                    End If
                    Select Case Left(strTemp, 1)
                        Case 1
                            strOutput = strOutput & "th"
                        Case Else
                            Select Case Right(strTemp, 1)
                                Case 1
                                    strOutput = strOutput & "st"
                                Case 2
                                    strOutput = strOutput & "cnd"
                                Case 3
                                    strOutput = strOutput & "rd"
                                Case Else
                                    strOutput = strOutput & "th"
                            End Select
                    End Select
                Case "w"
                    strOutput = strOutput & (DatePart("w", strDateTime) - 1)
                Case "Z"
                    strOutput = strOutput & DatePart("y", strDateTime)
                ' week
                Case "W"
                    strOutput = strOutput & DatePart("ww", strDateTime)
                ' month
                Case "B"
                    Select Case DatePart("m", strDateTime)
                        Case 1
                            strOutput = strOutput & "January"
                        Case 2
                            strOutput = strOutput & "February"
                        Case 3
                            strOutput = strOutput & "March"
                        Case 4
                            strOutput = strOutput & "April"
                        Case 5
                            strOutput = strOutput & "May"
                        Case 6
                            strOutput = strOutput & "June"
                        Case 7
                            strOutput = strOutput & "July"
                        Case 8
                            strOutput = strOutput & "August"
                        Case 9
                            strOutput = strOutput & "September"
                        Case 10
                            strOutput = strOutput & "October"
                        Case 11
                            strOutput = strOutput & "November"
                        Case 12
                            strOutput = strOutput & "December"
                    End Select
                Case "m"
                    If DatePart("m", strDateTime) < 10 Then
                        strOutput = strOutput & "0" & DatePart("m", strDateTime)  
                    Else
                        strOutput = strOutput & DatePart("m", strDateTime)
                    End If
                Case "M"
                    Select Case DatePart("m", strDateTime)
                        Case 1
                            strOutput = strOutput & "Jan"
                        Case 2
                            strOutput = strOutput & "Feb"
                        Case 3
                            strOutput = strOutput & "Mar"
                        Case 4
                            strOutput = strOutput & "Apr"
                        Case 5
                            strOutput = strOutput & "May"
                        Case 6
                            strOutput = strOutput & "Jun"
                        Case 7
                            strOutput = strOutput & "Jul"
                        Case 8
                            strOutput = strOutput & "Aug"
                        Case 9
                            strOutput = strOutput & "Sep"
                        Case 10
                            strOutput = strOutput & "Oct"
                        Case 11
                            strOutput = strOutput & "Nov"
                        Case 12
                            strOutput = strOutput & "Dec"
                    End Select
                Case "n"
                    strOutput = strOutput & DatePart("m", strDateTime)
                ' Case "t" ' number of days in given month
                ' year
                ' Case "L" ' whether it's a leap year
                ' Case "o"
                Case "Y"
                    strOutput = strOutput & DatePart("yyyy", strDateTime)
                Case "y"
                    strOutput = strOutput & Right(DatePart("yyyy", strDateTime), 2)
                ' time
                Case "a"
                    If DatePart("h", strDateTime) < 12 Then
                        strOutput = strOutput & "am"
                    Else 
                        strOutput = strOutput & "pm"
                    End If
                Case "A"
                    If DatePart("h", strDateTime) < 12 Then
                        strOutput = strOutput & "AM"
                    Else 
                        strOutput = strOutput & "PM"
                    End If
                ' Case "B" ' swatch
                Case "g"
                    If DatePart("h", strDateTime) = 0 Then
                        strOutput = strOutput & 12
                    ElseIf DatePart("h", strDateTime) <= 12 Then
                        strOutput = strOutput & DatePart("h", strDateTime)
                    Else
                        strOutput = strOutput & (DatePart("h", strDateTime) - 12)
                    End If
                Case "G"
                    strOutput = strOutput & DatePart("h", strDateTime)
                Case "h"
                    If DatePart("h", strDateTime) = 0 Then
                        strTemp = 12
                    ElseIf DatePart("h", strDateTime) <= 12 Then
                        strTemp = DatePart("h", strDateTime)
                    Else
                        strTemp = (DatePart("h", strDateTime) - 12)
                    End If
                    If strTemp < 10 Then
                        strOutput = strOutput & 0 & strTemp
                    Else
                        strOutput = strOutput & strTemp
                    End If
                Case "H"
                    If DatePart("h", strDateTime) < 10 Then
                        strOutput = strOutput & 0 & (DatePart("h", strDateTime))
                    Else
                        strOutput = strOutput & (DatePart("h", strDateTime))
                    End If
                Case "i"
                    If DatePart("n", strDateTime) < 10 Then
                        strOutput = strOutput & 0 & (DatePart("n", strDateTime))
                    Else
                        strOutput = strOutput & (DatePart("n", strDateTime))
                    End If
                Case "s"
                    If DatePart("s", strDateTime) < 10 Then
                        strOutput = strOutput & 0 & (DatePart("s", strDateTime))
                    Else
                        strOutput = strOutput & (DatePart("s", strDateTime))
                    End If
                ' Case "u" ' microseconds
                ' timezone
                ' Case "e" ' timezone identifier
                ' Case "I" ' daylight savings time boolean
                ' Case "O" ' difference to GMT (0x00)
                'Case "P" ' differenct to GMT (0x:00)
                ' Case "T" ' timezone abbreviation
                ' Case "Z" ' timezone offset in seconds
                ' full
                ' Case "c" ' IS0 8601
                ' Case "r" ' RFC 2822
                ' Case "U" ' seconds since Unix epoch
                Case ""
                    bolEscape = 1
                Case Else
                    strOutput = strOutput & Mid(strFormatString, intI, 1)
            End Select
        Else
            strOutput = strOutput & Mid(strFormatString, intI, 1)
            bolEscape = 0
        End If
    Next

    PHPFormatDateTime = strOutput
End Function

The second function uses a format string like with the standard *NIX date command. This is one of the many sites with information about this format. The similarly long function follows:

Function BASHFormatDateTime(strDateTime, strFormatString)
    Dim intI, strOutput, strTemp, bolEscape
    bolEscape = 0

    For intI = 1 to Len(strFormatString)
        If bolEscape = 1 then
            Select Case Mid(strFormatString, intI, 1)
                ' day
                Case "d" ' day of month (e.g, 01)
                    If DatePart("d", strDateTime) < 10 Then
                        strOutput = strOutput & "0" & DatePart("d", strDateTime)  
                    Else
                        strOutput = strOutput & DatePart("d", strDateTime)
                    End If
                Case "e" ' day of month, space padded; same as %_d
                    strOutput = strOutput & " " & DatePart("d", strDateTime)  
                Case "a" ' locale's abbreviated weekday name (e.g., Sun)
                    Select Case DatePart("w", strDateTime)
                        Case 1
                            strOutput = strOutput &  "Mon"
                        Case 2
                            strOutput = strOutput &  "Tue"
                        Case 3
                            strOutput = strOutput &  "Wed"
                        Case 4
                            strOutput = strOutput &  "Thu"
                        Case 5
                            strOutput = strOutput &  "Fri"
                        Case 6
                            strOutput = strOutput &  "Sat"
                        Case 7
                            strOutput = strOutput &  "Sun"
                    End Select
                Case "A" ' locale's full weekday name (e.g., Sunday)
                    Select Case DatePart("w", strDateTime)
                        Case 1
                            strOutput = strOutput &  "Monday"
                        Case 2
                            strOutput = strOutput &  "Tuesday"
                        Case 3
                            strOutput = strOutput &  "Wednesday"
                        Case 4
                            strOutput = strOutput &  "Thursday"
                        Case 5
                            strOutput = strOutput &  "Friday"
                        Case 6
                            strOutput = strOutput &  "Saturday"
                        Case 7
                            strOutput = strOutput &  "Sunday"
                    End Select
                Case "u" ' day of week (1..7); 1 is Monday
                    strOutput = strOutput & (DatePart("w", strDateTime))
                Case "w" '  day of week (0..6); 0 is Sunday
                    strOutput = strOutput & (DatePart("w", strDateTime, vbSaturday) - 1)
                Case "j" ' day of year (001..366)
                    strTemp = DatePart("y", strDateTime)
                    If strTemp < 10 Then
                        strOutput = strOutput & "00" & strTemp
                    ElseIf strTemp < 100 Then
                        strOutput = strOutput & "0" & strTemp
                    Else
                        strOutput = strOutput  & strTemp
                    End If
                ' week
                Case "U" ' week number of year, with Sunday as first day of week (00..53)
                    strTemp = DatePart("ww", strDateTime, vbSunday, vbSunday)
                    If strTemp < 10 Then
                        strOutput = strOutput & "0" & (strTemp)
                    Else
                        strOutput = strOutput  & (strTemp)
                    End If
                Case "W" ' week number of year, with Monday as first day of week (00..53)
                    strTemp = DatePart("ww", strDateTime, vbMonday, vbMonday)
                    If strTemp < 10 Then
                        strOutput = strOutput & "0" & (strTemp)
                    Else
                        strOutput = strOutput  & (strTemp)
                    End If
                'Case "g" ' last two digits of year of ISO week number
                '  strOutput = strOutput & DatePart("ww", strDateTime)
                ' Case "G" ' year of ISO week number (see %V); normally useful only with %V
                ' Case "V" ' ISO week number, with Monday as first day of week (01..53)
                ' month
                Case "m" ' month (01..12)
                    If DatePart("m", strDateTime) < 10 Then
                        strOutput = strOutput & "0" & DatePart("m", strDateTime)  
                    Else
                        strOutput = strOutput & DatePart("m", strDateTime)
                    End If
                Case "b", "h" ' locale's abbreviated month name (e.g., Jan)
                    Select Case DatePart("m", strDateTime)
                        Case 1
                            strOutput = strOutput & "Jan"
                        Case 2
                            strOutput = strOutput & "Feb"
                        Case 3
                            strOutput = strOutput & "Mar"
                        Case 4
                            strOutput = strOutput & "Apr"
                        Case 5
                            strOutput = strOutput & "May"
                        Case 6
                            strOutput = strOutput & "Jun"
                        Case 7
                            strOutput = strOutput & "Jul"
                        Case 8
                            strOutput = strOutput & "Aug"
                        Case 9
                            strOutput = strOutput & "Sep"
                        Case 10
                            strOutput = strOutput & "Oct"
                        Case 11
                            strOutput = strOutput & "Nov"
                        Case 12
                            strOutput = strOutput & "Dec"
                    End Select
                ' year
                Case "C" ' century; like %Y, except omit last two digits (e.g., 21)
                    strOutput = strOutput & Left(DatePart("yyyy", strDateTime), 2)
                Case "y" ' last two digits of year (00..99)
                    strOutput = strOutput & Right(DatePart("yyyy", strDateTime), 2)
                Case "Y" ' full year
                    strOutput = strOutput & DatePart("yyyy", strDateTime)
                ' time
                Case "P" ' like %p, but lower case
                    If DatePart("h", strDateTime) < 12 Then
                        strOutput = strOutput & "am"
                    Else 
                        strOutput = strOutput & "pm"
                    End If
                Case "p" ' locale's equivalent of either AM or PM; blank if not known
                    If DatePart("h", strDateTime) < 12 Then
                        strOutput = strOutput & "AM"
                    Else 
                        strOutput = strOutput & "PM"
                    End If
                Case "l" ' hour ( 1..12)
                    If DatePart("h", strDateTime) = 0 Then
                        strOutput = strOutput & 12
                    ElseIf DatePart("h", strDateTime) <= 12 Then
                        strOutput = strOutput & DatePart("h", strDateTime)
                    Else
                        strOutput = strOutput & (DatePart("h", strDateTime) - 12)
                    End If
                Case "k" ' hour ( 0..23)
                    strOutput = strOutput & DatePart("h", strDateTime)
                Case "I" ' hour (01..12)
                    If DatePart("h", strDateTime) = 0 Then
                        strTemp = 12
                    ElseIf DatePart("h", strDateTime) <= 12 Then
                        strTemp = DatePart("h", strDateTime)
                    Else
                        strTemp = (DatePart("h", strDateTime) - 12)
                    End If
                    If strTemp < 10 Then
                        strOutput = strOutput & 0 & strTemp
                    Else
                        strOutput = strOutput & strTemp
                    End If
                Case "H" ' hour (00..23)
                    If DatePart("h", strDateTime) < 10 Then
                        strOutput = strOutput & 0 & (DatePart("h", strDateTime))
                    Else
                        strOutput = strOutput & (DatePart("h", strDateTime))
                    End If
                Case "M" ' minute (00..59)
                    If DatePart("n", strDateTime) < 10 Then
                        strOutput = strOutput & 0 & (DatePart("n", strDateTime))
                    Else
                        strOutput = strOutput & (DatePart("n", strDateTime))
                    End If
                Case "S" ' second (00..60)
                    If DatePart("s", strDateTime) < 10 Then
                        strOutput = strOutput & 0 & (DatePart("s", strDateTime))
                    Else
                        strOutput = strOutput & (DatePart("s", strDateTime))
                    End If
                ' Case "N" ' nanoseconds
                ' Case "s" ' seconds since unix epoch
                ' Case "z", ":z" ..., "Z" all for timezone
                ' formatted
                Case "c"
                    strOutput = strOutput & BASHFormatDateTime(strDateTime, "%a %b %e %T %Y")
                Case "D"
                    strOutput = strOutput & BASHFormatDateTime(strDateTime, "%m/%d/%y")
                Case "F"
                    strOutput = strOutput & BASHFormatDateTime(strDateTime, "%Y-%m-%d")
                Case "r"
                    strOutput = strOutput & BASHFormatDateTime(strDateTime, "%I:%M:%S %p")
                Case "R"
                    strOutput = strOutput & BASHFormatDateTime(strDateTime, "%H:%M")
                Case "T"
                    strOutput = strOutput & BASHFormatDateTime(strDateTime, "%H:%M:%S")
                ' Case "x" ' locales date representation
                ' Case "X" ' locales time representation
                ' etc
                Case "n"
                    strOutput = strOutput & "<br />" ' or vbcrlf
                Case "t"
                    strOutput = strOutput & "    " ' or vbtab
                Case Else
                    strOutput = strOutput & Mid(strFormatString, intI, 1)
            End Select
            bolEscape = 0
        Else
            If Mid(strFormatString, intI, 1) = "%" Then
                bolEscape = 1
            Else
                strOutput = strOutput & Mid(strFormatString, intI, 1)
            End If
        End If
    Next

    BASHFormatDateTime = strOutput
End Function

For testing purposes, I stuck those in a file with this form and processor for testing:

If Request.Item("format") & "" <> "" Then
    Dim i, varDate, varOutput
    Dim varDatePart

    For i = 1 to  31
        'set date
        If i <= 24 then
            varDatePart = i - 1
        Else 
            varDatePart = 1
        End If

        'varDate = varDatePart & "/" & i
         If i < 10 Then
            varDate = "2009-01-0" & i & " " & varDatePart & ":" & (varDatePart + 10) & ":" & (varDatePart + 23)
        Else
            varDate = "2009-01-" & i & " " & varDatePart & ":" & (varDatePart + 10) & ":" & (varDatePart + 23)
        End If

        'Response.Write(PHPFormatDateTime(varDate, "F jS, Y") & "<br />")
        'Response.Write("Date: " & PHPFormatDateTime(varDate, "w d l the jS M(F) Z W m/d y(Y) g:i:s a G:i:s h:i:s A H:i:s") & "<br />")
        'Response.Write(DatePart("w", varDate) & "<br />")
        Select Case Request.Form("type")
            Case "PHP"
                Response.Write(PHPFormatDateTime(varDate, Request.Form("format"))&"<br />")
            Case "BASH"
                Response.Write(BASHFormatDateTime(varDate, Request.Form("format"))&"<br />")
        End Select
    Next
End If

I don’t code in classic ASP at all anymore, and I think .NET is taking over that segment of development, but hopefully this will help someone stuck with old servers anyway.

Published by

Toby

I am a quiet person from Northeast Ohio. I work as a web developer. I like computers, music, and many other things.

2 thoughts on “Formatting Dates in Classic ASP”

    1. I forget if that’s the one, but I know there was a date function I found that wasn’t available on our older server version. Looks like that one only has like 5 formatting possibilities anyway, so if we did have that available, it might wouldn’t have been capable enough.

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