Fix QueryString serializer of top-level string values

Author: mythz

src/ServiceStack.Text/QueryStringSerializer.cs

@@ -165,7 +165,8 @@ public static void WriteIDictionary(TextWriter writer, object oMap)
                 foreach (var key in map.Keys)
                 {
                     var dictionaryValue = map[key];
-                    if (dictionaryValue == null) continue;
+                    if (dictionaryValue == null) 
+                        continue;
 
                     if (writeKeyFn == null)
                     {
@@ -174,7 +175,11 @@ public static void WriteIDictionary(TextWriter writer, object oMap)
                     }
 
                     if (writeValueFn == null || isObjectDictionary)
-                        writeValueFn = Serializer.GetWriteFn(dictionaryValue.GetType());
+                    {
+                        writeValueFn = dictionaryValue is string
+                            ? (w,x) => w.Write(((string)x).UrlEncode())
+                            : Serializer.GetWriteFn(dictionaryValue.GetType());
+                    }
 
                     if (ranOnce)
                         writer.Write("&");

tests/ServiceStack.Text.Tests/QueryStringSerializerTests.cs

@@ -48,6 +48,17 @@ public void Can_Serialize_Unicode_Query_String()
                 Is.EqualTo("A=%e5%b4%91%e2%a8%b9%e5%a0%a1%ea%81%80%e1%a2%96%e3%a4%b9%c3%ac%e3%ad%a1%ec%a4%aa%e9%8a%ac"));
         }
 
+        [Test]
+        public void Does_serialize_Poco_and_string_dictionary_with_encoded_data()
+        {
+            var msg = "Field with comma, to demo. ";
+            Assert.That(QueryStringSerializer.SerializeToString(new D { A = msg }),
+                Is.EqualTo("A=Field+with+comma,+to+demo.+"));
+
+            Assert.That(QueryStringSerializer.SerializeToString(new D { A = msg }.ToStringDictionary()),
+                Is.EqualTo("A=Field+with+comma,+to+demo.+"));
+        }
+
         class Empty { }
 
         [Test]