Fix WiFi helper retry/reset behavior and test API usage

README.md

@@ -121,6 +121,59 @@ var success = WaitForValidIPAndDate(true, NetworkInterfaceType.Ethernet, cs.Toke
 // if success is true then you are connected
 ```
 
+### Retry and reconfiguration
+
+#### Retry after timeout
+
+Token-based methods (`ConnectDhcp`, `ScanAndConnectDhcp`, `ConnectFixAddress`) are retryable. If a connection attempt times out, call the method again:
+
+```csharp
+bool connected = false;
+while (!connected)
+{
+    CancellationTokenSource cs = new(30000);
+    connected = WifiNetworkHelper.ConnectDhcp(Ssid, Password, requiresDateTime: true, token: cs.Token);
+    if (!connected)
+    {
+        Debug.WriteLine($"Not ready, status: {WifiNetworkHelper.Status}");
+        Thread.Sleep(5000);
+    }
+}
+```
+
+#### Switching networks or restarting
+
+To switch to a different SSID or restart the event-based helper, call `Reset()` first:
+
+```csharp
+// Disconnect from current network if needed
+WifiNetworkHelper.Disconnect();
+
+// Reset the helper so it can be reconfigured
+WifiNetworkHelper.Reset();
+
+// Connect to a different SSID
+CancellationTokenSource cs = new(30000);
+WifiNetworkHelper.ConnectDhcp("NewSSID", "NewPassword", token: cs.Token);
+```
+
+The same applies to the event-based `SetupNetworkHelper`:
+
+```csharp
+WifiNetworkHelper.Reset();
+WifiNetworkHelper.SetupNetworkHelper("NewSSID", "NewPassword");
+```
+
+#### `Reconnect()` vs. `ConnectDhcp()`
+
+`Reconnect()` does **not** actively send join credentials. It only waits for the platform's automatic reconnection (configured via `WifiReconnectionKind.Automatic`) to produce a valid IP address. Use it only when credentials are already stored on the device and the platform is expected to reconnect automatically.
+
+If you need an explicit reconnect with credentials, use `ConnectDhcp()` instead.
+
+#### `NetworkReady` behaviour
+
+When using `SetupNetworkHelper()`, `NetworkReady` is reset when the connection is lost and re-signaled when it is restored, accurately reflecting live network state. Code that previously assumed `NetworkReady` would remain set permanently after first connect should be updated to handle transient disconnects.
+
 ## Feedback and documentation
 
 For documentation, providing feedback, issues and finding out how to contribute please refer to the [Home repo](https://github.com/nanoframework/Home).

System.Device.Wifi/Properties/AssemblyInfo.cs

@@ -12,7 +12,7 @@
 
 ////////////////////////////////////////////////////////////////
 // update this whenever the native assembly signature changes //
-[assembly: AssemblyNativeVersion("100.2.0.0")]
+[assembly: AssemblyNativeVersion("100.2.0.1")]
 ////////////////////////////////////////////////////////////////
 
 // Setting ComVisible to false makes the types in this assembly not visible 

Tests/NFUnitTestWifiConnection/ConnectToWifiFixIPAddressTests.cs

@@ -46,7 +46,7 @@ public void TestFixIPAddress_01()
             Assert.IsNull(WifiNetworkHelper.HelperException);
 
             // need to reset this internal flag to allow calling the NetworkHelper again
-            WifiNetworkHelper.ResetInstance();
+            WifiNetworkHelper.Reset();
         }
 
         [TestMethod]
@@ -62,7 +62,7 @@ public void TestFixedIPAddress_02()
             Assert.IsTrue(WifiNetworkHelper.NetworkReady.WaitOne(10000, true));
 
             // need to reset this internal flag to allow calling the NetworkHelper again
-            WifiNetworkHelper.ResetInstance();
+            WifiNetworkHelper.Reset();
         }
     }
 }

Tests/NFUnitTestWifiConnection/ConnectToWifiWithCredentialsScanTests.cs

@@ -42,7 +42,7 @@ public void TestNormalConnectionScanAndConnect()
             Assert.IsNull(WifiNetworkHelper.HelperException);
 
             // need to reset this internal flag to allow calling the NetworkHelper again
-            WifiNetworkHelper.ResetInstance();
+            WifiNetworkHelper.Reset();
         }
 
         [TestMethod]
@@ -58,7 +58,7 @@ public void TestDhcp_01()
             Assert.IsNull(WifiNetworkHelper.HelperException);
 
             // need to reset this internal flag to allow calling the NetworkHelper again
-            WifiNetworkHelper.ResetInstance();
+            WifiNetworkHelper.Reset();
         }
 
         [TestMethod]
@@ -70,7 +70,7 @@ public void TestDhcp_02()
             Assert.IsTrue(WifiNetworkHelper.NetworkReady.WaitOne(10000, true));
 
             // need to reset this internal flag to allow calling the NetworkHelper again
-            WifiNetworkHelper.ResetInstance();
+            WifiNetworkHelper.Reset();
         }
 
         [TestMethod]
@@ -84,6 +84,9 @@ public void TestSingleUsage()
                 // call twice, it's a NO NO and should throw an exception
                 WifiNetworkHelper.SetupNetworkHelper();
             });
+
+            // clear static state so this test doesn't affect later tests
+            WifiNetworkHelper.Reset();
         }
     }
 }

Tests/NFUnitTestWifiConnection/ConnectToWifiWithCredentialsTests.cs

@@ -57,8 +57,67 @@ public void TestNormalConnection()
             Assert.IsTrue(success);
             Assert.IsNull(WifiNetworkHelper.HelperException);
 
-            // need to reset this internal flag to allow calling the NetworkHelper again
-            WifiNetworkHelper.ResetInstance();
+            WifiNetworkHelper.Reset();
+        }
+
+        [TestMethod]
+        public void TestRetryAfterTimeout()
+        {
+            // First attempt: very short timeout so it expires
+            CancellationTokenSource cs1 = new(1000);
+            var firstResult = WifiNetworkHelper.ConnectDhcp(
+                Ssid,
+                Password,
+                token: cs1.Token);
+
+            Assert.IsFalse(firstResult, "First call should have timed out");
+
+            // Second attempt with a longer timeout — must not throw InvalidOperationException
+            CancellationTokenSource cs2 = new(15000);
+            var secondResult = WifiNetworkHelper.ConnectDhcp(
+                Ssid,
+                Password,
+                requiresDateTime: true,
+                token: cs2.Token);
+
+            DisplayLastError(secondResult);
+            Assert.IsTrue(secondResult, "Second attempt should succeed after retry");
+
+            WifiNetworkHelper.Reset();
+        }
+
+        [TestMethod]
+        public void TestResetAllowsEventBasedRestart()
+        {
+            // Use event-based helper once
+            WifiNetworkHelper.SetupNetworkHelper(Ssid, Password);
+
+            bool connected = WifiNetworkHelper.NetworkReady.WaitOne(15000, true);
+            Assert.IsTrue(connected, "Expected to connect on first event-based attempt");
+
+            // Reset and restart with same credentials
+            WifiNetworkHelper.Reset();
+            WifiNetworkHelper.SetupNetworkHelper(Ssid, Password);
+
+            connected = WifiNetworkHelper.NetworkReady.WaitOne(15000, true);
+            Assert.IsTrue(connected, "Expected to connect after Reset + SetupNetworkHelper restart");
+
+            WifiNetworkHelper.Reset();
+        }
+
+        [TestMethod]
+        public void TestSingleUsageEventBased()
+        {
+            Assert.ThrowsException(typeof(System.InvalidOperationException), () =>
+            {
+                // First call is OK
+                WifiNetworkHelper.SetupNetworkHelper(Ssid, Password);
+
+                // Second call without Reset must throw
+                WifiNetworkHelper.SetupNetworkHelper(Ssid, Password);
+            });
+
+            WifiNetworkHelper.Reset();
         }
     }
 }

Tests/NFUnitTestWifiConnection/ConnectToWifiWithoutCredentialsTests.cs

@@ -34,7 +34,7 @@ public void TestReconnection()
             Assert.IsNull(WifiNetworkHelper.HelperException);
 
             // need to reset this internal flag to allow calling the NetworkHelper again
-            WifiNetworkHelper.ResetInstance();
+            WifiNetworkHelper.Reset();
         }
     }
 }