DateTimeGMTToHttpStr@TDateTime

Converts a native TDateTime to an RFC 2822-compliant date and time string.

Parameters	Description
GMTValue	Date and time value to convert to an RFC 2822 date and time format.

Returns

String - RFC 2822-compliant date and time value.

Description

DateTimeGMTToHttpStr is a String function used to convert a native TDateTime value to a string in RFC 822-compliant data and time form.

The return value for DateTimeGMTToHttpStr is the string containing the following data and time specification:

ABNF Syntax

Copy Code

date-time   =  [ day "," ]date time          ;  dd mm yy
                                             ;  hh:mm:ss zzz

day         =  "Mon"/"Tue"/"Wed"/"Thu"/"Fri"/"Sat"/"Sun"

date        =  1*2DIGIT month 2DIGIT         ; day month year
                                             ; e.g. 20 Jun 82

month       = "Jan"/"Feb"/"Mar"/"Apr"/"May"/"Jun"/
               "Jul"/"Aug"/"Sep"/"Oct"/"Nov"/"Dec"

time        =  hour zone                    ; ANSI and Military

hour        =  2DIGIT":"2DIGIT[":"2DIGIT]   ; 00:00:00 - 23:59:59

zone        =  "UT"  / "GMT"                ; Universal Time
                                            ; North American : UT
            /  "EST" / "EDT"                ;  Eastern:  - 5/ - 4
            /  "CST" / "CDT"                ;  Central:  - 6/ - 5
            /  "MST" / "MDT"                ;  Mountain: - 7/ - 6
            /  "PST" / "PDT"                ;  Pacific:  - 8/ - 7
            /  1ALPHA                       ; Military: Z = UT;
                                            ;  A:-1; (J not used)
                                            ;  M:-12; N:+1; Y:+12
            / ( ("+" / "-") 4DIGIT )        ; Local differential
                                            ;  hours+min. (HHMM)

Semantics

If included, day-of-week must be the day implied by the date specification.

Time zone may be indicated in several ways. "UT" is Universal Time (formerly called "Greenwich Mean Time"); "GMT" is permitted as a reference to Universal Time.

The military standard uses a single character for each zone. "Z" is Universal Time. "A" indicates one hour earlier, and "M" indicates 12 hours ear lier; "N" is one hour later, and "Y" is 12 hours later. The letter "J" is not used.

The other remaining two forms are taken from ANSI standard X3.51-1975. One allows explicit indication of the amount of offset from UT; the other uses common 3-character strings for indicating time zones in North America.

DateTimeGMTToHttpStr generates the date and time format used in request and response headers for the HTTP protocol.