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lang: ja-jp
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# MessagePack の `MessagePackSerializer` で DateTime型をシリアライズすると 世界標準時の時間となる C# 2021-09-17

> http://neue.cc/category/programming/page/3

## `NativeDateTimeResolver` を使用すると解決する

public class MessagePackSerializerOption
{
    public static MessagePackSerializerOptions Option;

    static MessagePackSerializerOption()
    {
        // StandardResolverによる解決の前にNativeDateTimeResolverで解決させる
        IFormatterResolver datetimeResolver = MessagePack.Resolvers.CompositeResolver.Create(
            NativeDateTimeResolver.Instance,
            ContractlessStandardResolverAllowPrivate.Instance
            );

        Option = ContractlessStandardResolverAllowPrivate.Options
            .WithCompression(MessagePackCompression.Lz4Block)
            .WithResolver(datetimeResolver);
            ;
    }
}

public class MessagePackSerializerOption
{
    public static MessagePackSerializerOptions Option;

    static MessagePackSerializerOption()
    {
        // StandardResolverによる解決の前にNativeDateTimeResolverで解決させる
        IFormatterResolver datetimeResolver = MessagePack.Resolvers.CompositeResolver.Create(
            NativeDateTimeResolver.Instance,
            ContractlessStandardResolver.Instance
            );

        Option = ContractlessStandardResolver.Options
            .WithCompression(MessagePackCompression.Lz4Block)
            .WithResolver(datetimeResolver);
            ;
    }
}

###### tags: `MessagePack` `MagicOnion` `gRPC` `シリアライズ` `C#`