How to convert DATE to a HTTP string date in ASP

DateToHTTPDate and DateFromHTTP functions (source). Enables conversion between OLE datetime (8byte VARIANT-DATE) and http datetime (plain text). Useful for If-Modified-Since and Last-Modified headers.
Using :

Response.AddHeader "Last-Modified", DateToHTTPDate(Now()-1)

Source :

'Converts date (19991022 11:08:38)
'to http form (Fri, 22 Oct 1999 12:08:38 GMT)
function DateToHTTPDate(ByVal OleDATE)
  Const GMTdiff = #01:00:00#
  OleDATE = OleDATE + GMTdiff
	DateToHTTPDate = engWeekDayName(OleDATE) & _
	", " & Right("0" & Day(OleDATE),2) & " " & engMonthName(OleDATE) & _
	" " & Year(OleDATE) & " " & Right("0" & Hour(OleDATE),2) & _
	":" & Right("0" & Minute(OleDATE),2) & ":" & Right("0" & Second(OleDATE),2) & " GMT"
End Function 

Function engWeekDayName(dt)
	Dim Out
	Select Case WeekDay(dt,1)
		Case 1:Out="Sun"
		Case 2:Out="Mon"
		Case 3:Out="Tue"
		Case 4:Out="Wed"
		Case 5:Out="Thu"
		Case 6:Out="Fri"
		Case 7:Out="Sat"
	End Select
	engWeekDayName = Out
End Function

Function engMonthName(dt)
	Dim Out
	Select Case Month(dt)
		Case 1:Out="Jan"
		Case 2:Out="Feb"
		Case 3:Out="Mar"
		Case 4:Out="Apr"
		Case 5:Out="May"
		Case 6:Out="Jun"
		Case 7:Out="Jul"
		Case 8:Out="Aug"
		Case 9:Out="Sep"
		Case 10:Out="Oct"
		Case 11:Out="Nov"
		Case 12:Out="Dec"
	End Select
	engMonthName = Out
End Function

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<A
 Href="https://www.motobit.com/tips/detpg_DateToHTTPDate/"
 Title="ASP (VBS) function converting DATE data
	type to http string date
	(like Fri, 22 Oct 1999
	12:08:38 GMT)."
>How to convert DATE to a HTTP string date in ASP</A>

How to convert DATE to a HTTP string date in ASPMOTOBIT.COM

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Copyright and use this code