Merge pull request #49967 from wesmc7777/master

Update SignalR secret to use (:) with the config API

Author: PRMerger15

articles/azure-signalr/signalr-quickstart-dotnet-core.md

@@ -89,16 +89,21 @@ In this section, you will add the [Secret Manager tool](https://docs.microsoft.c
 
         dotnet restore
 
-3. Add a secret named *Azure__SignalR__ConnectionString* to Secret Manager. This secret is a hierarchical config value, and a colon (:) may not work on all platforms. Double underscore (__), as used by this secret, is supported by all platforms.  This secret will contain the connection string to access your SignalR Service resource. *Azure__SignalR__ConnectionString* is the default configuration key that SignalR looks for in order to establish a connection. Replace the value in the command below with the connection string for your SignalR Service resource.
+3. Add a secret named *Azure:SignalR:ConnectionString* to Secret Manager. 
+
+    This secret will contain the connection string to access your SignalR Service resource. *Azure:SignalR:ConnectionString* is the default configuration key that SignalR looks for in order to establish a connection. Replace the value in the command below with the connection string for your SignalR Service resource.
 
     This command must be executed in the same directory as the *.csproj* file.
 
     ```
-    dotnet user-secrets set Azure__SignalR__ConnectionString "Endpoint=<Your endpoint>;AccessKey=<Your access key>;"    
+    dotnet user-secrets set Azure:SignalR:ConnectionString "Endpoint=<Your endpoint>;AccessKey=<Your access key>;"    
     ```
 
     Secret Manager will only be used for testing the web app while it is hosted locally. In a later tutorial, you will deploy the chat web app to Azure. Once the web app is deployed to Azure, you will use an application setting instead of storing the connection string with Secret Manager.
 
+    This secret is a accessed with the configuration API. A colon (:) works in the configuration name with the configuration API on all supported platforms, see [Configuration by environment](https://docs.microsoft.com/aspnet/core/fundamentals/configuration/index?tabs=basicconfiguration&view=aspnetcore-2.0#configuration-by-environment). 
+
+
 4. Open *Startup.cs* and update the `ConfigureServices` method to use Azure SignalR Service by calling the `services.AddSignalR().AddAzureSignalR()` method:
 
     ```csharp
@@ -109,7 +114,7 @@ In this section, you will add the [Secret Manager tool](https://docs.microsoft.c
     }
     ```
 
-    By not passing a parameter to `AddAzureSignalR()`, this code uses the default configuration key, *Azure__SignalR__ConnectionString*, for the SignalR Service resource connection string.
+    By not passing a parameter to `AddAzureSignalR()`, this code uses the default configuration key, *Azure:SignalR:ConnectionString*, for the SignalR Service resource connection string.
 
 5. Also in *Startup.cs*, update the `Configure` method by replacing the call to `app.UseStaticFiles()` with the following code and save the file.