Question

why the NetworkInterface.GetIsNetworkAvailable() method always returns true,when i debug it on my windows phone 7 device?not emulator,is it sure that “NetworkInterface.NetworkInterfaceType==NetworkInterface.None” means a device does’t get network access?how can i detect whether a device connected a network that has intenert access? i tried this link,Zune-Detection-and-Network-Awareness,but the NetworkInterface.GetIsNetworkAvailable() method always returns true,which stumbled me a lot.Thanks for your help.

Answer 1

Read the documentation for the method. Here is what MSDN has to say:

A network connection is considered to be available if any network
interface is marked “up” and is not a loopback or tunnel interface.

There are many cases in which a device or computer is not connected to
a useful network but is still considered available and
GetIsNetworkAvailable will return true. For example, if the device
running the application is connected to a wireless network that
requires a proxy, but the proxy is not set, GetIsNetworkAvailable will
return true. Another example of when GetIsNetworkAvailable will return
true is if the application is running on a computer that is connected
to a hub or router where the hub or router has lost the upstream
connection.

Generally, you could say that this method is generally prone to errors. I would recommend taking the approach of failed requests – have a couple of URLs to test against and check if HTTP/DNS resolve requests go through. If some of them pass – there is a connection. If all fail – chances are you are not connected.

Here is a sample.