/// <summary>
/// Creates a <see cref="JsonConverter{T}"/> instance that converts <typeparamref name="T?"/> values.
/// </summary>
/// <typeparam name="T">The generic definition for the underlying nullable type.</typeparam>
/// <param name="options">The <see cref="JsonSerializerOptions"/> to use for serialization and deserialization.</param>
/// <returns>A <see cref="JsonConverter{T}"/> instance that converts <typeparamref name="T?"/> values</returns>
/// <remarks>This API is for use by the output of the System.Text.Json source generator and should not be called directly.</remarks>
public static JsonConverter <T?> GetNullableConverter <T>(JsonSerializerOptions options) where T : struct
{
if (options is null)
{
ThrowHelper.ThrowArgumentNullException(nameof(options));
}
JsonConverter <T> underlyingConverter = GetTypedConverter <T>(options.GetConverterFromTypeInfo(typeof(T)));
return(new NullableConverter <T>(underlyingConverter));
}
internal override void WriteAsPropertyNameCore(Utf8JsonWriter writer, object?value, JsonSerializerOptions options, bool isWritingExtensionDataProperty)
{
// This converter does not handle nulls.
Debug.Assert(value != null);
Type runtimeType = value.GetType();
JsonConverter runtimeConverter = options.GetConverterFromTypeInfo(runtimeType);
if (runtimeConverter == this)
{
ThrowHelper.ThrowNotSupportedException_DictionaryKeyTypeNotSupported(runtimeType, this);
}
runtimeConverter.WriteAsPropertyNameCoreAsObject(writer, value, options, isWritingExtensionDataProperty);
}
public override JsonConverter CreateConverter(Type typeToConvert, JsonSerializerOptions options)
{
Debug.Assert(typeToConvert.GetGenericArguments().Length > 0);
Type valueTypeToConvert = typeToConvert.GetGenericArguments()[0];
JsonConverter valueConverter = options.GetConverterFromTypeInfo(valueTypeToConvert);
Debug.Assert(valueConverter != null);
// If the value type has an interface or object converter, just return that converter directly.
if (!valueConverter.TypeToConvert.IsValueType && valueTypeToConvert.IsValueType)
{
return(valueConverter);
}
return(CreateValueConverter(valueTypeToConvert, valueConverter));
}