Add utility method for allowing .NET Standard 2.0 libraries using the SDK to know whether they are using the .NET Framework version of the SDK. (#3934)

Author: normj

generator/.DevConfigs/91bbaabd-8a52-43d9-ae0b-410bfb215318.json

@@ -0,0 +1,9 @@
+{
+  "core": {
+    "updateMinimum": false,
+    "type": "patch",
+    "changeLogMessages": [
+      "Add utility method for allowing .NET Standard 2.0 libraries using the SDK to know whether they are using the .NET Framework version of the SDK."
+    ]
+  }
+}

sdk/src/Core/Amazon.Util/AWSSDKUtils.cs

@@ -946,6 +946,21 @@ private static bool IsWindows()
 #endif
         }
 
+        /// <summary>
+        /// This method returns true if the variant of the SDK being used is the .NET Framework target. This allows
+        /// libraries using .NET Standard 2.0 like AWSSDK.Extensions.NETCore.Setup to know at runtime if they are
+        /// using the .NET Framework version and if so make decisions on what APIs it should call.
+        /// </summary>
+        /// <returns>True if the version of the SDK is .NET Framework variant.</returns>
+        public static bool IsNETFramework()
+        {
+#if NETFRAMEWORK
+            return true;
+#else
+            return false;
+#endif
+        }
+
         #region The code in this region has been minimally adapted from Microsoft's PathInternal.Windows.cs class as of 11/19/2019.  The logic remains the same.
         /// <summary>
         /// Returns true if the path specified is relative to the current drive or working directory.
@@ -1018,7 +1033,7 @@ public static string UrlEncode(string data, bool path)
         /// URL encodes a string per the specified RFC. If the path property is specified,
         /// the accepted path characters {/+:} are not encoded.
         /// </summary>
-        /// <param name="rfcNumber">RFC number determing safe characters</param>
+        /// <param name="rfcNumber">RFC number determining safe characters</param>
         /// <param name="data">The string to encode</param>
         /// <param name="path">Whether the string is a URL path or not</param>
         /// <returns>The encoded string</returns>