Title: "Quiet" online checking
Question:
Answer:
Sometimes it's required to check if a user has an active Internet connection,
but you don't want the DUN dialog box to popup by your code. Well, it was not
easy to find out a method for that, but finally a hint by Henri Fournier in the
Newsgroups gave me the idea for the following 2 powerful lines:
USES
WinInet;
..
..
function InternetConnected: Boolean;
CONST
// local system uses a modem to connect to the Internet.
INTERNET_CONNECTION_MODEM = 1;
// local system uses a local area network to connect to the Internet.
INTERNET_CONNECTION_LAN = 2;
// local system uses a proxy server to connect to the Internet.
INTERNET_CONNECTION_PROXY = 4;
// local system's modem is busy with a non-Internet connection.
INTERNET_CONNECTION_MODEM_BUSY = 8;
VAR
dwConnectionTypes : DWORD;
BEGIN
dwConnectionTypes :=
INTERNET_CONNECTION_MODEM +
INTERNET_CONNECTION_LAN +
INTERNET_CONNECTION_PROXY;
Result := InternetGetConnectedState(@dwConnectionTypes,0);
END;
That's all! Have fun..
Note from 05-Dec-98: I had to find that this solution only works under
Windows 95/98 - Since the required DLL routine doesn't seem to be
implemented by Windows NT, this OS produces an error during program
startup when you refer to Wininet.
If anyone knows a better method to do Online-Checks, please let me know!