c# - Web API 2.0 IHttpActionResult 缓存

Question

我正在使用此代码返回对象内容，但我想缓存添加 Cache-Control header 的响应。

[AllowAnonymous]
[Route("GetPublicContent")]
[HttpGet]
 public IHttpActionResult GetPublicContent([FromUri]UpdateContentDto dto)
        {

            if (dto == null)
                return BadRequest();

            var content = _contentService.GetPublicContent(dto);
            if (content == null)
                return BadRequest();
            return new Ok(content);

        }

就是这样!谢谢!!

Answer 1

创建一个继承自 OkNegotiatedContentResult<T> 的新类:

public class CachedOkResult<T> : OkNegotiatedContentResult<T>
{
    public CachedOkResult(T content, TimeSpan howLong, ApiController controller) : base(content, controller)
    {
        HowLong = howLong;
    }

    public CachedOkResult(T content, IContentNegotiator contentNegotiator, HttpRequestMessage request, IEnumerable<MediaTypeFormatter> formatters) 
    : base(content, contentNegotiator, request, formatters) { }

    public TimeSpan HowLong { get; private set; }


    public override async Task<HttpResponseMessage> ExecuteAsync(CancellationToken cancellationToken)
    {
        var response = await base.ExecuteAsync(cancellationToken);
        response.Headers.CacheControl = new CacheControlHeaderValue() {
            Public = false,
            MaxAge = HowLong
        };

        return response;
    }
}

要在您的 Controller 中使用它，只需返回 CachedOkResult 的一个新实例即可类:

public async Task<IHttpActionResult> GetSomething(string id)
{
    var value = await GetAsyncResult(id);
    // cache result for 60 seconds
    return new CachedOkResult<string>(value, TimeSpan.FromSeconds(60), this);
}

标题将像这样通过电线:

Cache-Control:max-age=60
Content-Length:551
Content-Type:application/json; charset=utf-8
... other headers snipped ...