Check Internet Connection by
http://www.c-sharpcorner.com/Code/2003/Aug/CheckInternetConnection.asp
How to Detect a Dialup Connection?
http://www.c-sharpcorner.com/Code/2003/May/DetectingDialUpConnection.asp
http://www.c-sharpcorner.com/Code/2003/Aug/CheckInternetConnection.asp
How to Detect a Dialup Connection?
http://www.c-sharpcorner.com/Code/2003/May/DetectingDialUpConnection.asp
解决方案 »
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