Programtically Submit Form And Read Results

[Steve Bouffe]

Been digging around the forums but cant find anything.

I'm using UrlDownLoadToFile to read web pages. Is it possible to simulate a form submit and read the result in the same way? I cant use the following method as the form contents are too large.

ie. http://myserver/cgi-bin/app.cgi?name...address=street ........ etc

The form is as follows.

<form name="input" action="app.cgi" method="get">
<input type="hidden" name="name" value="steve">
<input type="hidden" name="address" value="street">

...... etc
</form>

[Adam J. Drake]

This may work:

#INCLUDE "WININET.INC"
%HTTP_BUFFER_LENGTH=16000

FUNCTION WEBREQUEST(sURL AS STRING, FormData AS STRING) EXPORT AS STRING

    LOCAL iReturn       AS LONG
    LOCAL iRead         AS LONG
    LOCAL hInternet     AS DWORD
    LOCAL hConn         AS DWORD
    LOCAL hRequest      AS DWORD
    LOCAL sHeaders      AS ASCIIZ*1200
    LOCAL sData         AS STRING
    LOCAL sBuffer       AS STRING
    LOCAL ErrMsg        AS STRING
    LOCAL sReturnData   AS STRING
    LOCAL myurl         AS ASCIIZ*%MAX_PATH
    LOCAL fd            AS STRING
    LOCAL sMethod       AS ASCIIZ*%MAX_PATH
    LOCAL ws            AS ASCIIZ*%MAX_PATH

    fd=FormData

    ws=sURL
    ws = REMAIN$(ws,"://")
    ws = MID$(ws,INSTR(ws,"/")+1)

    hInternet = InternetOpen(BYVAL %NULL, %INTERNET_OPEN_TYPE_PRECONFIG, BYVAL %NULL, BYVAL %NULL, 0)
    IF hInternet = 0 THEN
        ErrMsg = "InternetOpen failed"
        GOTO Finish
    END IF

    myurl=EXTRACT$(REMAIN$(sURL, "://"),"/")

    hConn = InternetConnect(hInternet, myurl, 80, "", "", %INTERNET_SERVICE_HTTP, 0, 0)
    IF hConn = 0 THEN
        ErrMsg = "InternetConnect failed"
        GOTO Finish
    END IF

    sMethod="POST"
    hRequest = httpOpenRequest(hConn, sMethod, ws, "HTTP/1.1", BYVAL %NULL, BYVAL %NULL, %INTERNET_FLAG_RELOAD OR %INTERNET_FLAG_NO_CACHE_WRITE OR %INTERNET_FLAG_PRAGMA_NOCACHE, %NULL)
    IF hRequest = 0 THEN
        ErrMsg = "httpOpenRequest failed."
        GOTO Finish
    END IF

    sHeaders = "Content-Type: application/x-www-form-urlencoded"+$CRLF+_
               "Content-Length: "+FORMAT$(LEN(fd))+$CRLF+_
               "Connection: Keep-Alive "+$CRLF+$CRLF

    sData=fd

    IF httpSendRequest(hRequest, sHeaders, LEN(sHeaders), BYVAL STRPTR(sData), LEN(sData)) = 0 THEN
        ErrMsg = "httpSendRequest failed."
        GOTO Finish
    END IF

    iRead = 0
    sReturnData = ""
    sBuffer = SPACE$(%HTTP_BUFFER_LENGTH)
    iReturn = InternetReadFile(hRequest, BYVAL STRPTR(sBuffer), %HTTP_BUFFER_LENGTH, iRead)

    DO
        
        IF iRead = 0 THEN
            IF iReturn <> 0 THEN
                EXIT DO
            END IF
        END IF

        sReturnData = sReturnData + LEFT$(sBuffer, iRead)
        iRead = 0
        sBuffer = SPACE$(%HTTP_BUFFER_LENGTH)
        iReturn = InternetReadFile(hRequest, BYVAL STRPTR(sBuffer), %HTTP_BUFFER_LENGTH, iRead)

    LOOP

Finish:

   IF hRequest<>0 THEN
       InternetCloseHandle hRequest
   END IF
   
   IF hConn<>0 THEN
       InternetCloseHandle hConn
   END IF
   
   IF hInternet<>0 THEN
       InternetCloseHandle hInternet
   END IF
   
   FUNCTION = IIF$(TRIM$(ErrMsg)="",sReturnData,ErrMsg)

END FUNCTION

[Steve Bouffe]

This works really well, just call with the url and the formdata as "user=john&pass=secret&session=10234" etc.

I think that this will be of good use to lots of us!

[Steve Bouffe]

Some time ago I was trying to get URLDownloadToFile to work in a pbcc cgi app with no success.

I can get the function here WEBREQUEST to work with no problems.

Although some URLs I can download using WEBREQUEST with no form data, some servers will not work properly.

Is there any way to modify the code to download just URL's that I can add to my cgi app?

At the moment I've got a pbcc app running on the server's desktop that monitors a directory. The cgi app dumps a request file and the program running on the server reads the file, performs a URLDownLoadToFile and writes the result in the results directory which the cgi app wait for. Bit of a hack but it deos work.