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How to check an Internet connection

Title: How to check an Internet connection Question: Often in an App that works with Internet you need to know is user connected to Internet or not? I think below is most flexible sotution Answer: To make sure in this point you need to import InetIsOffline function from URL.DLL: function InetIsOffline(Flag: Integer): Boolean; stdcall; external 'URL.DLL'; and then simply call this function in place you want to check connection status: if InetIsOffline(0) then ShowMessage('This computer is not connected to Internet!') else ShowMessage(You are connected to Internet!'); This function return TRUE if the local system isn't connected to Internet, or FALSE if it's connected or no attempt has been yet made to connect. Notes: Variable Flag is ignored, so always use zero. This DLL is usual installed on most computers. It is always installed on Win98 or comes with Internet Explorer 4 or later, Office 97 etc. Read more on MSDN. Original: http://msdn.microsoft.com/library/psdk/shellcc/shell/Functions/InetIsOffline.htm