Question: how to check network connection?

[HppZ]

NetworkHelper.Instance.ConnectionInformation.IsInternetAvailable
NetworkInterface.GetIsNetworkAvailable()
are True
even when WLAN switch is off for my app, and my app can't access network. so I need a way to check network connection.

[mrlacey]

It all depends on what you mean by "check network connection"

System.Net.NetworkInformation.NetworkInterface.GetIsNetworkAvailable() only checks if there is a local network that your machine can connect to.
Similarly, Microsoft.Toolkit.Uwp.Connectivity.NetworkHelper.Instance.ConnectionInformation.IsInternetAvailable is a wrapper the types of network settings available on the machine.

If you want to know about physical hardware and switches available, keep looking at the namespaces and types where you already are.

If you want to check if you can connect to a specific location on the internet or other network, your best option is to actually make a request to that location.

There are lots of potential variables that can influence whether a connection to a remote resource can be made and successful communication can occur (even if that's only requesting and returning some data).
Your app may need to handle the following differently. There is no single "is a connection available" test that will work for all apps and scenarios.

• What if you can access some internet resources but not others?
• What if the server you want to connect to is down, but you can connect to any other service on the internet?
• What if you can reach the desired endpoint but there's a security/certificate problem with the connection?
• What if you can reach the desired endpoint but there's an authorization issue?
• What if you can reach the host but some endpoints are throttling requests or returning errors?
• What if the URL you want is up but recent DNS changes haven't fully propagated to all servers? (So it looks up to some users but not others.)
• What if some routers or ISPs are blocking or modifying requests to this endpoint?
• What if some routers or ISPs are caching requests to the server you're trying to connect to?
• What if you're downloading a large amount of data and it puts the connection beyond what's allowed partway through the download process?
• What if you lose connection partway through?

Asking "can I connect to the internet, or even a specific endpoint" is never the full story and even if you can it doesn't guarantee you'll be able to make successful requests.
Yes, you can improve the user experience by how you handle failures, device configurations issues, or other scenarios that prevents a connection from being made, but don't rely on this.
If you do have specific questions about specific connectivity scenarios, please be explicit about your specific scenario and requirements.

[HppZ]

THANKS!

not physical hardware and switches, it is in Windows Settings:

Network & Internet > Wi-Fi > Choose apps that can use your Wi-Fi data.

actually I want to detect if this switch is on or off for my app, but found no way.

[andrewleader]

Hey HppZ, thanks for asking this question! And Matt, thanks for the super detailed answers 😊

@HppZ, so your ask is for an API that tells you if the toggle switch in Network & Internet > Wi-Fi > Choose apps that can use your Wi-Fi data. is on or off on your app, correct? I can check with the team to see if an API for that exists, and if not, see whether it's been considered.

Alternatively, if NetworkInterface.GetIsNetworkAvailable() returned false when that switch is disabled for your app, would that be an acceptable solution too?

[andrewleader]

Actually @HppZ I can't even find that setting on my computers, I checked both a Windows 10 and Windows 11 PC. Can you send me a screenshot of that settings page and where you found it?

[riverar]

This feature requires CTA policy to be enabled (China). @HppZ Try using AppCapability.Create("wifiData").CheckAccess() to check if your app is being limited.

[riverar]

@andrewleader If you're curious, the feature looks like this. It's actually really neat, wish it was generally available to all of us!

[HppZ]

THANK YOU ALL.

This feature requires CTA policy to be enabled (China). @HppZ Try using AppCapability.Create("wifiData").CheckAccess() to check if your app is being limited.

Do you have any doc about CTA policy and AppCapability wifiData? I found nothing on google.

[riverar]

@HppZ Did it work?

There's not a lot of documentation in the public, I'm afraid.

https://docs.microsoft.com/bs-latn-ba/windows-hardware/customize/desktop/unattend/microsoft-windows-deviceaccess-setregionspecificprivacyaccesspolicy is how OEMs/device manufacturers turn it on. There's no real documentation on what it affects, sorry.

@andrewleader might be able to get more info from the team!

[HppZ]

@riverar it does not work.

AppCapability.Create("wifiData").CheckAccess() always return Allowed whether that switch is on or off.

[riverar]

@HppZ Is it a runFullTrust desktop app? UWP app? Or?

[HppZ]

pure UWP app.

[riverar]

@HppZ OK, I'll try building a sample. One more question, can you screenshot "winver" please and paste it here?