Ask .NET Which Proxy It Would Use for a URL
Inspect default proxy selection for an exact destination, including bypass decisions and explicit HttpClient overrides.
Ask the default policy about the exact URL that fails:
var destination = new Uri("https://example.com/");
var proxy = HttpClient.DefaultProxy;
Console.WriteLine(proxy.IsBypassed(destination));
Console.WriteLine(proxy.GetProxy(destination));Use the System and System.Net.Http namespaces. Keep private returned endpoint information out of public logs.
| Observation | Meaning |
|---|---|
IsBypassed(destination) | Whether this policy selects direct routing for that URL. |
GetProxy(destination) | A policy result; WebProxy can return the original destination when bypassed. |
| A real request through the failing client | Evidence about whether its selected route was usable. |
| A destination-side source-address report | The exit observed for that request. |
HttpClient.DefaultProxy supplies default routing when the handler has no explicit proxy configuration, and its initialization depends on the platform. Another assigned proxy or disabled proxy use can choose differently. Inspect the actual handler, not just a fresh diagnostic client.
A service may also run with another user environment. Keep selected proxy, bypass decision and request result separate when comparing it with an interactive application. This code opens no destination connection and measures no exit IP; collect such evidence through the same client and route if needed.