Synchronous browser operation

[Kerry Farmer]

I just discovered this piece of code posted by Cliff Nicholls in 2014

 #COMPILE EXE
#DIM ALL
#INCLUDE ONCE "Win32Api.inc"  
SUB OpenWebPage(PageToOpen AS STRING)    
ShellExecute(BYVAL %NULL, "open", PageToOpen + CHR$(0), BYVAL %NULL, BYVAL %NULL,%SW_SHOWNORMAL)
END SUB  
FUNCTION PBMAIN () AS LONG      
OpenWebPage "http://www.powerbasic.com/support/pbforums/"
END FUNCTION

It does just what I want to do. Namely open a web page when I may not know the default browser.

However, it operates asynchronously ie hands control back to the program immediately.

Is there any easy way that I can change this to acting synchronously? ie not handing control back to the program until the browser program terminates?

I use PBCC, Windows 10

Thanks

Kerry

[Juergen Kuehlwein]

Hi Kerry,


"SHELL" (as a statement) should do what you want.


JK

[Kerry Farmer]

"SHELL" (as a statement) should do what you want.

Nope, but thanks for trying

Shell gets me error 53

FUNCTION PBMAIN () AS LONG
     SHELL "http://www.powerbasic.com/support/pbforums/"
     PRINT ERR
     PRINT "zz"
     WAITKEY$
END FUNCTION

You can SHELL 'browser_name (including path) url' and that works. But I want to do it where I do not know the browser name. Actually, I want to do it on lots of computers where the browser could be any browser.

[Dale Yarker]

Looks to me like you had SHELL Statement in post 3. So that's not it.

What is the default program (on your PC) for file type .htm, .html. etc (web types)? For example on my PC opening a .htm file or URL opens it in IE without specifying IE first. Opening a .txt uses NotePad, etc, etc.

Cheers,

[Dale Yarker]

Just realized your URL is incomplete. A browser (or the server) might add index.htm invisibly, Windows won't.

Cheers,

[Michael Mattias]

Is there any easy way that I can change this to acting synchronously? ie not handing control back to the program until the browser program terminates?

Easy? Define 'Easy!' And how about asking for a "good" way? Or an "accepted" way? Or maybe even "a way which offers more control?"

Sheesh, everyone wants either "easy", "fast" or "cheap."

Whatever happened to those who wanted to do things The Right Way?

That said (off my chest) .... instead of ShellExecute, use ShellExecuteEx() as per this demo: Win 32: Monitor Process with ShellExecuteEx June 22, 2001 (That's pretty new, so you may have missed it). You will have to detect when the launched program ends (WaitForSingleObject()) but at least you will be doing that under full control of your program.

FWIW, that's a replacement for SHELL, so a properly-constructed SHELL statement or function can be made to work.

[Bud Durland]

Sheesh, everyone wants either "easy", "fast" or "cheap."

I always tell my customers (users at work) -- "you can have Good, Fast, Cheap. Pick two"

[Stuart McLachlan]

One way is to use FindExecutable to locate the default application for the file type and then SHELL to it. Here's one way to do that:

FUNCTION GetStandardProgram(fileext AS WSTRING) AS WSTRING
   LOCAL wszExecName AS WSTRINGZ * %MAX_PATH
   LOCAL wszFName AS WSTRINGZ * %MAX_PATH
   LOCAL wszPath AS WSTRINGZ * %MAX_PATH

   LOCAL lngRet AS LONG
   lngRet = gettemppathW(BYVAL %MAX_PATH,wszPath)
   wszFName = wszPath & "testfile." & fileext
   OPEN wszFName FOR OUTPUT AS #1
   CLOSE #1
   lngRet =  FindExecutableW(wszFName, BYVAL 0, wszExecName)
   KILL wszFName
   SELECT CASE lngRet
     CASE 2
         FUNCTION = "Error in GetStandardProgram: " & wszFName & " not found"
    CASE 3
         FUNCTION = "Error in GetStandardProgram: Invalid path in " & wszFName
    CASE 5
         FUNCTION = "Error in GetStandardProgram: " & wszFName & " cannot be accessed"
    CASE 8
         FUNCTION = "Error in GetStandardProgram: Out of memory or Resources"
    CASE 31
         FUNCTION = "Error in GetStandardProgram: There is no default executable for " & wszFName
    CASE ELSE
         FUNCTION = wszExecName
    END SELECT
END FUNCTION

But see https://blogs.msdn.microsoft.com/old...08-00/?p=93274..

With that cautionary note, GetStandardProgram("html") does return the correct browser executable for me.

[Mikael T]

To get the system default browser you could use AssocQueryString and then start the browser with the desirered link.

#COMPILE EXE
#DIM ALL
#INCLUDE ONCE "Shlwapi.inc"

FUNCTION PBMAIN
  ? GetAssociatedExe(".html")
  WAITKEY$
END FUNCTION

FUNCTION GetAssociatedExe(fileExt AS STRINGZ) AS STRING
  LOCAL resultBuffer AS ASCIIZ * %MAX_PATH

  IF AssocQueryString(%ASSOCF_INIT_IGNOREUNKNOWN, _
                      %ASSOCSTR_EXECUTABLE, _
                      fileExt, _
                      "", _
                      resultBuffer, _
                      SIZEOF(resultBuffer)) = %S_OK THEN FUNCTION = resultBuffer
END FUNCTION

Mikael