Check the network connection status

The following sectionCodeReturns the network connection status of the current computer.
 

[Dllimport (" Wininet. dll ")]
 Private   Static   Extern   Bool Internetgetconnectedstate ( Ref   Uint Connected, Uint Reserved );

 Static   Uint Uconnection = 0x20;

 /// <Summary> 
 /// Returns true if it have detected an active Internet connection. 
 /// </Summary> 
 Public   Static   Bool Hasinternetconnection
{
 Get { Return Internetgetconnectedstate ( Ref Uconnection, 0 );}
}

In addition:

To check for
Internet connection in. net, we can use getisnetworkavailable Method
Defined in the system. net. Network-Information namespace. But it returns
A boolean value that denotes whether any network connection is
Available and does not say about Internet connectivity. To make sure we
Also have Internet access, the reliable method is to attempt to ping
Host

...
UsingSystem. net. networkinformation;
...
Public BoolIsconnectedtointernet ()
{
StringHost =Http://www.c-sharpcorner.com;
BoolResult =False;
PingP =New Ping();
Try
{
PingreplyReply = P. Send (host, 3000 );
If(Reply. Status =Ipstatus. Success)
Return True;
}
Catch{}
ReturnResult;
}

Or we can use a simple API function internetgetconnectedstate. This function takes two arguments:

TheFirst oneIs an integer usedOut
Keyword, which means that after calling the function, the variable will
Contain an integer that describes the connection state.

TheSecond oneIs a reserved variable that must be set to 0.

Using System;
Using System. runtime;
Using System. runtime. interopservices;
Public Class Internetcs
{
// Creating the extern function...
[Dllimport ("wininet. dll")]
Private Extern Static Bool Internetgetconnectedstate ( Out Int Description, Int Reservedvalue );
// Creating a function that uses the API function...
Public Static Bool Isconnectedtointernet ()
{
Int DESC;
Return Internetgetconnectedstate ( Out DESC, 0 );
}
}