Allow overriding of serialization of Guid formats

Author: mythz

src/ServiceStack.Text/Json/JsonTypeSerializer.cs

@@ -168,13 +168,17 @@ public void WriteNullableTimeSpan(TextWriter writer, object oTimeSpan)
 
         public void WriteGuid(TextWriter writer, object oValue)
         {
-            WriteRawString(writer, ((Guid)oValue).ToString("N"));
+            WriteRawString(writer, JsConfig<Guid>.RawSerializeFn != null
+                ? JsConfig<Guid>.RawSerializeFn((Guid) oValue)
+                : ((Guid) oValue).ToString("N"));
         }
 
         public void WriteNullableGuid(TextWriter writer, object oValue)
         {
             if (oValue == null) return;
-            WriteRawString(writer, ((Guid)oValue).ToString("N"));
+            WriteRawString(writer, JsConfig<Guid>.RawSerializeFn != null
+                ? JsConfig<Guid>.RawSerializeFn((Guid)oValue)
+                : ((Guid)oValue).ToString("N"));
         }
 
         public void WriteBytes(TextWriter writer, object oByteValue)

src/ServiceStack.Text/Jsv/JsvTypeSerializer.cs

@@ -144,14 +144,18 @@ public void WriteNullableTimeSpan(TextWriter writer, object oTimeSpan)
 
 		public void WriteGuid(TextWriter writer, object oValue)
 		{
-			writer.Write(((Guid)oValue).ToString("N"));
+		    writer.Write(JsConfig<Guid>.RawSerializeFn != null
+		        ? JsConfig<Guid>.RawSerializeFn((Guid) oValue)
+		        : ((Guid) oValue).ToString("N"));
 		}
 
-		public void WriteNullableGuid(TextWriter writer, object oValue)
+        public void WriteNullableGuid(TextWriter writer, object oValue)
 		{
 			if (oValue == null) return;
-			writer.Write(((Guid)oValue).ToString("N"));
-		}
+            writer.Write(JsConfig<Guid>.RawSerializeFn != null
+                ? JsConfig<Guid>.RawSerializeFn((Guid)oValue)
+                : ((Guid)oValue).ToString("N"));
+        }
 
 		public void WriteBytes(TextWriter writer, object oByteValue)
 		{

tests/ServiceStack.Text.Tests/JsonTests/CustomRawSerializerTests.cs

@@ -72,6 +72,20 @@ public void Reset_ShouldClear_JsConfigT_CachedFunctions()
             json = JsonSerializer.SerializeToString(test);
             // Assert:
             Assert.That(json, Is.EquivalentTo("{\"Name\":\"Test\",\"Data\":\"AQIDBAU=\"}"));
-        }        
+        }
+
+        [Test]
+        public void Can_override_Guid_serialization_format()
+        {
+            var guid = new Guid("ADFA988B-01F6-490D-B65B-63750F869496");
+
+            Assert.That(guid.ToJson().Trim('"'), Is.EqualTo("adfa988b01f6490db65b63750f869496"));
+            Assert.That(guid.ToJsv(), Is.EqualTo("adfa988b01f6490db65b63750f869496"));
+
+            JsConfig<Guid>.RawSerializeFn = x => x.ToString();
+
+            Assert.That(guid.ToJson().Trim('"'), Is.EqualTo("adfa988b-01f6-490d-b65b-63750f869496"));
+            Assert.That(guid.ToJsv(), Is.EqualTo("adfa988b-01f6-490d-b65b-63750f869496"));
+        }
     }
 }