ASP.NET Core Newtonsoft.Json设置全局输出风格

ASP.NET Core 2.x

在Startup.cs中设置

/// <summary>
/// This method gets called by the runtime. Use this method to add services to the container.
/// </summary>
/// <param name="services"></param>
public void ConfigureServices(IServiceCollection services)
{
    services.AddMvc().AddJsonOptions(options =>
      {
          //设置输出snake_case风格
          options.SerializerSettings.ContractResolver = new DefaultContractResolver() { NamingStrategy = new SnakeCaseNamingStrategy() };
          //设置输出camelCase风格
          // options.SerializerSettings.ContractResolver = new DefaultContractResolver() { NamingStrategy = new CamelCaseNamingStrategy() };
          //默认为PascalCase风格
          //options.SerializerSettings.ContractResolver = new DefaultContractResolver() { NamingStrategy = new DefaultNamingStrategy() };
          //包含时区信息
          options.SerializerSettings.DateTimeZoneHandling = DateTimeZoneHandling.Local;
          //包含Null值的序列化
          options.SerializerSettings.NullValueHandling = NullValueHandling.Include;
      });
}

ASP.NET Core 3.x

在Startup.cs中设置

/// <summary>
/// This method gets called by the runtime. Use this method to add services to the container.
/// </summary>
/// <param name="services"></param>
public void ConfigureServices(IServiceCollection services)
{
    services.AddControllers()
    .AddNewtonsoftJson(options =>
    {
          //设置输出snake_case风格
          options.SerializerSettings.ContractResolver = new DefaultContractResolver() { NamingStrategy = new SnakeCaseNamingStrategy() };
          //设置输出camelCase风格
          // options.SerializerSettings.ContractResolver = new DefaultContractResolver() { NamingStrategy = new CamelCaseNamingStrategy() };
          //默认为PascalCase风格
          //options.SerializerSettings.ContractResolver = new DefaultContractResolver() { NamingStrategy = new DefaultNamingStrategy() };
          //包含时区信息
          options.SerializerSettings.DateTimeZoneHandling = DateTimeZoneHandling.Local;
          //包含Null值的序列化
          options.SerializerSettings.NullValueHandling = NullValueHandling.Include;
    });
}

另外需要说一下Swagger的支持，在ASP.NET Core 3.0之前，Swagger默认的序列化工具使用Newtonsoft.Json，所以配置了Newtonsoft.Json的全局输出风格后Swagger界面的输出也会一致。但是在ASP.NET Core 3.0时，由于ASP.NET Core 3.x内置了System.Text.Json，Swagger(Swashbuckle>=5.0.0) 默认使用System.Text.Json进行序列化操作，所以如果想使Swagger继续使用Newtonsoft.Json需要额外配置

• 引入Swashbuckle.AspNetCore.Newtonsoft
  在Startup.cs中

/// <summary>
/// This method gets called by the runtime. Use this method to add services to the container.
/// </summary>
/// <param name="services"></param>
public void ConfigureServices(IServiceCollection services)
{
    //Swagger序列化操作使用Newtonsoft.Json
    services.AddSwaggerGenNewtonsoftSupport();
}

Reference

• Swashbuckle.AspNetCore