web api: 添加数据到 HttpResponseMessage

Question

我的网站 api 中有一个操作正在返回 HttpResponseMessage:

public async Task<HttpResponseMessage> Create([FromBody] AType payload)
{
    if (payload == null)
    {
        throw new ArgumentNullException(nameof(payload));
    }

    await Task.Delay(1);

    var t = new T { Id = 0, Name = payload.tName, Guid = Guid.NewGuid() };

    var response = new MyResponse { T = t };

    var result = new HttpResponseMessage(HttpStatusCode.OK) { Content = new ObjectContent(typeof(MyResponse), response, new JsonMediaTypeFormatter { SerializerSettings = { NullValueHandling = Newtonsoft.Json.NullValueHandling.Ignore } }) };

    return result;
}

现在，我的问题是，如果发出请求并且请求的 Content-Type 是 application/xml，我应该使用 xml formatter.

放置响应正文

有没有办法使用通用 class 并让框架根据请求的内容类型决定在运行时使用什么格式化程序？

Answer 1

在请求上使用 CreateResponse 扩展方法，它将允许基于关联请求进行内容协商。如果您想根据请求的内容类型强制内容类型，请从请求中获取它并将其包含在创建响应重载中。

public class MyApitController : ApiController {
    [HttpPost]
    public async Task<HttpResponseMessage> Create([FromBody] AType payload) {
        if (payload == null) {
            throw new ArgumentNullException(nameof(payload));
        }

        await Task.Delay(1);

        var t = new T { Id = 0, Name = payload.tName, Guid = Guid.NewGuid() };

        var response = new MyResponse { T = t };

        var contentType = Request.Content.Headers.ContentType;

        var result = Request.CreateResponse(HttpStatusCode.OK, response, contentType);

        return result;
    }

}

理想情况下，返回的类型应基于请求表明它想要接受的内容。该框架确实允许在该主题上具有灵活性。

查看此以获取更多信息Content Negotiation in ASP.NET Web API

Answer 2

一个更简单的方法是使用 Web API2 ApiController 中的便捷方法。

[HttpPost]
public async Task<IHttpActionResult> Create([FromBody] AType payload)
{
    if (payload == null) 
    {
        return BadRequest("Must provide payload");
    }

    await Task.Delay(1);

    var t = new T { Id = 0, Name = payload.tName, Guid = Guid.NewGuid() };

    var response = new MyResponse { T = t };

    return Ok(response);
}

web api: 添加数据到 HttpResponseMessage

web api: add data to the HttpResponseMessage

c#

asp.net-web-api2

content-negotiation

mediatypeformatter