Internet connected or not

[chrisjx2002]

Very interesting. Thanks for the sharing

[PeteWG]

Check Connectivity of Internet based on the result of PING command
You can also use this function to check computer IP in LAN before performing any action to avoid program crash

Interesting code. thanks for sharing!
however I'm a bit sceptical about its reliability, since i got:

"Ping to 0.1.0.1 Succesful"

for xurl := "0.1.0.1"

(needless to say that doing a C:\>ping 0.1.0.1 (in command line)
returns as expected "PING: transmission failed. General failure.")

regards,

---
Pete

[edk]

however I'm a bit sceptical about its reliability, since i got:

"Ping to 0.1.0.1 Succesful"

for xurl := "0.1.0.1"

(needless to say that doing a C:\>ping 0.1.0.1 (in command line)
returns as expected "PING: transmission failed. General failure.")

Strange, I've got message "Internet Connection Not Available" and variable xerrdescription is 1231. Tested on Win10 32b and HMG 3.4.4

[PeteWG]

This is probably the simplest way with PINGing:

Code: Select all

FUNCTION Main()
  // https://msdn.microsoft.com/en-us/library/windows/desktop/aa384346(v=vs.85).aspx
  LOCAL lIsInternet := If(HMG_CallDLL("Wininet.dll", 0, "InternetCheckConnection", "http://www.google.com", 1 /*FLAG_ICC_FORCE_CONNECTION*/, 0) == 1, .T., .F.)

  MsgBox("Is internet: " + HB_ValToStr(lIsInternet))

RETURN NIL

Nice suggestion. Thank you very much!
(Although I didn't understand what you mean by "with PINGing").

Now, as a general remark I'd say that DLL calls is not the preffered method, for me, to exploit windows functionality,
when it's easy to implement relevant functions "natively" in harbour.

f.e.:

Code: Select all

PROCEDURE Main
   LOCAL isInet := InternetCheckConnection( "https://www.google.com" )
  
   ? "=============================="
   ? "Internet " + If ( isInet, "available!", "not available" )
   ? InternetCheckConnection() // -> .T. (it works even without Url, as it's documented)

   RETURN

#pragma BEGINDUMP
#include <hbapi.h>
#include <windows.h>
#include <wininet.h>

HB_FUNC( INTERNETCHECKCONNECTION )
{
   const char * cUrl = hb_parc( 1 );
   hb_retl( (HB_BOOL) InternetCheckConnection( cUrl, FLAG_ICC_FORCE_CONNECTION, 0 ) );
}
#pragma ENDDUMP

I think this approach is much more faster and safer than calling DLLs.
However I'd like to hear different opinions (if any) on that.

regards,

---
Pete

[PeteWG]

Strange, I've got message "Internet Connection Not Available" and variable xerrdescription is 1231. Tested on Win10 32b and HMG 3.4.4

Really? then it's strange indeed...

Please note that I have built/run the sample using HMG-extended with MinGW32 7.1.0 on Windows 7 pro.
Don't know if it's enough to explain the different results, though. (i'm going to build with HMG official and see..)

[huiyi_ch]

Check Connectivity of Internet based on the result of PING command
You can also use this function to check computer IP in LAN before performing any action to avoid program crash

Interesting code. thanks for sharing!
however I'm a bit sceptical about its reliability, since i got:

"Ping to 0.1.0.1 Succesful"

for xurl := "0.1.0.1"

(needless to say that doing a C:\>ping 0.1.0.1 (in command line)
returns as expected "PING: transmission failed. General failure.")

regards,

---
Pete

I've got message "Internet Connection Not Available",too. Tested on WindowsXp 32b and HMG 3.4.4

[PeteWG]

...Tested on Win10 32b and HMG 3.4.4

Nope! On Win 7 and HMG 3.4.2 and 3.4.3 (i have no installed 3.4.4)
it still gives "Ping to 0.1.0.1 Succesful"

It's very probable the culprit be the "usual suspect" (different Win versions).

regards,

---
Pete

[PeteWG]

I've got message "Internet Connection Not Available",too. Tested on WindowsXp 32b and HMG 3.4.4

Well! i attach the executable i have made with HMG 3.4.3.
Could you please test it to see what it returns on your machine/OS?

regards,

---
Pete

[edk]

"Internet Connection Not Available" on Win10 Pro 32 and WinXp on VM and Server2012r2

WinXp on VM.PNG (14.96 KiB) Viewed 5463 times

Win10.png (5.22 KiB) Viewed 5463 times

Serwer2012R2.png (6.38 KiB) Viewed 5461 times

[bpd2000]

I confirm same result as posted by EDK