Add PlatformApis.IsUnityIOS

src/csharp/Grpc.Core/Internal/PlatformApis.cs

@@ -42,6 +42,7 @@ namespace Grpc.Core.Internal
         static readonly bool isMono;
         static readonly bool isNetCore;
         static readonly bool isUnity;
+        static readonly bool isUnityIOS;
         static readonly bool isXamarin;
         static readonly bool isXamarinIOS;
         static readonly bool isXamarinAndroid;
@@ -63,7 +64,25 @@ namespace Grpc.Core.Internal
             isNetCore = false;
 #endif
             isMono = Type.GetType("Mono.Runtime") != null;
-            isUnity = Type.GetType(UnityEngineApplicationClassName) != null;
+
+            // Unity
+            var unityApplicationClass = Type.GetType(UnityEngineApplicationClassName);
+            if (unityApplicationClass != null)
+            {
+                isUnity = true;
+                // Consult value of Application.platform via reflection
+                // https://docs.unity3d.com/ScriptReference/Application-platform.html
+                var platformProperty = unityApplicationClass.GetTypeInfo().GetProperty("platform");
+                var unityRuntimePlatform = platformProperty?.GetValue(null)?.ToString();
+                isUnityIOS = (unityRuntimePlatform == "IPhonePlayer");
+            }
+            else
+            {
+                isUnity = false;
+                isUnityIOS = false;
+            }
+
+            // Xamarin
             isXamarinIOS = Type.GetType(XamarinIOSObjectClassName) != null;
             isXamarinAndroid = Type.GetType(XamarinAndroidObjectClassName) != null;
             isXamarin = isXamarinIOS || isXamarinAndroid;
@@ -97,6 +116,14 @@ namespace Grpc.Core.Internal
             get { return isUnity; }
         }
 
+        /// <summary>
+        /// true if running on Unity iOS, false otherwise.
+        /// </summary>
+        public static bool IsUnityIOS
+        {
+            get { return isUnityIOS; }
+        }
+
         /// <summary>
         /// true if running on a Xamarin platform (either Xamarin.Android or Xamarin.iOS),
         /// false otherwise.