Install-Package Microsoft.AspNetCore.Mvc.Versioning 

public class Startup
{
  public Startup(IConfiguration configuration)
  {
    Configuration = configuration;
  }
  public IConfiguration Configuration { get; }

  // This method gets called by the runtime. Use this method to add services to the container.
  public void ConfigureServices(IServiceCollection services)
  {
    //根据需要设置，以下内容
    services.AddApiVersioning(apiOtions =>
    {
      //返回响应标头中支持的版本信息
      apiOtions.ReportApiVersions = true;
      //此选项将用于不提供版本的请求。默认情况下, 假定的 API 版本为1.0
      apiOtions.AssumeDefaultVersionWhenUnspecified = true;
      //缺省api版本号，支持时间或数字版本号
      apiOtions.DefaultApiVersion = new ApiVersion(1, 0);
      //支持MediaType、Header、QueryString 设置版本号;缺省为QueryString、UrlSegment设置版本号;后面会详细说明对于作用
      apiOtions.ApiVersionReader = ApiVersionReader.Combine(
        new MediaTypeApiVersionReader("api-version"),
        new HeaderApiVersionReader("api-version"),
        new QueryStringApiVersionReader("api-version"),
        new UrlSegmentApiVersionReader());
    });
    services.AddControllers();
  }

  // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
  public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
  {
    if (env.IsDevelopment())
    {
      app.UseDeveloperExceptionPage();
    }
    app.UseHttpsRedirection();

    //使用ApiVersioning
    app.UseApiVersioning();
    app.UseRouting();
    app.UseAuthorization();
    app.UseEndpoints(endpoints =>
    {
      endpoints.MapControllers();
    });
  }
}

namespace WebAPIVersionDemo.Controllers
{
  [ApiController]
  [Route("[controller]")]
  //Deprecated=true:表示v1即将弃用，响应头中返回
  [ApiVersion("1.0", Deprecated = true)]
  [ApiVersion("2.0")]public class WeatherForecastController : ControllerBase
  {
    private static readonly string[] Summaries = new[]{"Freezing", "Bracing", "Chilly", "Cool", "Mild", "Warm", "Balmy", "Hot", "Sweltering", "Scorching"};
 
    [HttpGet]
    public IEnumerable<WeatherForecast> Get()
    {
      var rng = new Random();
      return Enumerable.Range(1, 5).Select(index => new WeatherForecast
      {
        Date = DateTime.Now.AddDays(index),
        TemperatureC = rng.Next(-20, 55),
        Summary = $"v1:{Summaries[rng.Next(Summaries.Length)]}"
      })
      .ToArray();
    }    
  }
}

[Route("/api/v{version:apiVersion}/[controller]")]

apiOtions.ApiVersionReader = ApiVersionReader.Combine(
        new MediaTypeApiVersionReader("api-version"),
        new HeaderApiVersionReader("api-version"));

[HttpGet]
[MapToApiVersion("3.0")]
public IEnumerable<WeatherForecast> GetV3()
{
  //获取版本
  string v = HttpContext.GetRequestedApiVersion().ToString();
  var rng = new Random();
  return Enumerable.Range(1, 1).Select(index => new WeatherForecast
  {
    Date = DateTime.Now.AddDays(index),
    TemperatureC = rng.Next(-20, 55),
    Summary = $"v{v}:{Summaries[rng.Next(Summaries.Length)]}"
  })
  .ToArray();
}

//swaggerui 包
Install-Package Swashbuckle.AspNetCore
//api版本
Install-Package Microsoft.AspNetCore.Mvc.Versioning.ApiExplorer 

public class Startup
{
  /// <summary>
  /// Api版本提者信息
  /// </summary>
  private IApiVersionDescriptionProvider provider;

  // This method gets called by the runtime. Use this method to add services to the container.
  public void ConfigureServices(IServiceCollection services)
  {
    services.AddControllers();
     
    //根据需要设置，以下内容
    services.AddApiVersioning(apiOtions =>
    {
      //返回响应标头中支持的版本信息
      apiOtions.ReportApiVersions = true;
      //此选项将用于不提供版本的请求。默认情况下, 假定的 API 版本为1.0
      apiOtions.AssumeDefaultVersionWhenUnspecified = true;
      //缺省api版本号，支持时间或数字版本号
      apiOtions.DefaultApiVersion = new ApiVersion(1, 0);
      //支持MediaType、Header、QueryString 设置版本号;缺省为QueryString设置版本号
      apiOtions.ApiVersionReader = ApiVersionReader.Combine(
          new MediaTypeApiVersionReader("api-version"),
          new HeaderApiVersionReader("api-version"),
          new QueryStringApiVersionReader("api-version"),
          new UrlSegmentApiVersionReader());
    });


    services.AddVersionedApiExplorer(option =>
    {
      option.GroupNameFormat = "接口：'v'VVV";
      option.AssumeDefaultVersionWhenUnspecified = true;
    });

    this.provider = services.BuildServiceProvider().GetRequiredService<IApiVersionDescriptionProvider>();
    services.AddSwaggerGen(options =>
    {
      foreach (var description in provider.ApiVersionDescriptions)
      {
        options.SwaggerDoc(description.GroupName,
            new Microsoft.OpenApi.Models.OpenApiInfo()
            {
              Title = $"接口 v{description.ApiVersion}",
              Version = description.ApiVersion.ToString(),
              Description = "切换版本请点右上角版本切换"
            }
        );
      }
      options.IncludeXmlComments(this.GetType().Assembly.Location.Replace(".dll", ".xml"), true);
    });

  }

  // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
  public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
  {
    //……  
  
    //使用ApiVersioning
    app.UseApiVersioning();

    //启用swaggerui，绑定api版本信息
    app.UseSwagger();
    app.UseSwaggerUI(c =>
    {
      foreach (var description in provider.ApiVersionDescriptions)
      {
        c.SwaggerEndpoint($"/swagger/{description.GroupName}/swagger.json", description.GroupName.ToUpperInvariant());
      }
    });

    //……  
  }
}