Enable nullable annotations for Volo.Abp.Json.Newtonsoft

framework/src/Volo.Abp.Json.Newtonsoft/Volo.Abp.Json.Newtonsoft.csproj

@@ -5,6 +5,8 @@
 
     <PropertyGroup>
         <TargetFrameworks>netstandard2.0;netstandard2.1;net7.0</TargetFrameworks>
+        <Nullable>enable</Nullable>
+        <WarningsAsErrors>Nullable</WarningsAsErrors>
         <AssemblyName>Volo.Abp.Json.Newtonsoft</AssemblyName>
         <PackageId>Volo.Abp.Json.Newtonsoft</PackageId>
         <AssetTargetFallback>$(AssetTargetFallback);portable-net45+win8+wp8+wpa81;</AssetTargetFallback>

framework/src/Volo.Abp.Json.Newtonsoft/Volo/Abp/Json/Newtonsoft/AbpDateTimeConverter.cs

@@ -31,7 +31,7 @@ public class AbpDateTimeConverter : DateTimeConverterBase, ITransientDependency
         return objectType == typeof(DateTime) || objectType == typeof(DateTime?);
     }
 
-    public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
+    public override object? ReadJson(JsonReader reader, Type objectType, object? existingValue, JsonSerializer serializer)
     {
         var nullable = Nullable.GetUnderlyingType(objectType) != null;
         if (reader.TokenType == JsonToken.Null)
@@ -46,7 +46,7 @@ public class AbpDateTimeConverter : DateTimeConverterBase, ITransientDependency
 
         if (reader.TokenType == JsonToken.Date)
         {
-            return _clock.Normalize(reader.Value.To<DateTime>());
+            return _clock.Normalize(reader.Value!.To<DateTime>());
         }
 
         if (reader.TokenType != JsonToken.String)
@@ -72,11 +72,11 @@ public class AbpDateTimeConverter : DateTimeConverterBase, ITransientDependency
             }
         }
 
-        var date = DateTime.Parse(dateText, _culture, _dateTimeStyles);
+        var date = DateTime.Parse(dateText!, _culture, _dateTimeStyles);
         return _clock.Normalize(date);
     }
 
-    public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
+    public override void WriteJson(JsonWriter writer, object? value, JsonSerializer serializer)
     {
         if (value != null)
         {
@@ -97,7 +97,7 @@ public class AbpDateTimeConverter : DateTimeConverterBase, ITransientDependency
         }
         else
         {
-            throw new JsonSerializationException($"Unexpected value when converting date. Expected DateTime or DateTimeOffset, got {value.GetType()}.");
+            throw new JsonSerializationException($"Unexpected value when converting date. Expected DateTime or DateTimeOffset, got {value?.GetType()}.");
         }
     }
 

framework/src/Volo.Abp.Json.Newtonsoft/Volo/Abp/Json/Newtonsoft/AbpNewtonsoftJsonSerializer.cs

@@ -26,12 +26,12 @@ public class AbpNewtonsoftJsonSerializer : IJsonSerializer, ITransientDependency
 
     public T Deserialize<T>(string jsonString, bool camelCase = true)
     {
-        return JsonConvert.DeserializeObject<T>(jsonString, CreateJsonSerializerOptions(camelCase));
+        return JsonConvert.DeserializeObject<T>(jsonString, CreateJsonSerializerOptions(camelCase))!;
     }
 
     public object Deserialize(Type type, string jsonString, bool camelCase = true)
     {
-        return JsonConvert.DeserializeObject(jsonString, type, CreateJsonSerializerOptions(camelCase));
+        return JsonConvert.DeserializeObject(jsonString, type, CreateJsonSerializerOptions(camelCase))!;
     }
 
     private readonly static ConcurrentDictionary<object, JsonSerializerSettings> JsonSerializerOptionsCache =