ASP.NET MVC 4应用程序调用远程WebAPI

Question

我以前创建了几个ASP.NET MVC应用程序,但我以前从未使用过WebAPI.我想知道如何创建一个简单的MVC 4应用程序,通过WebAPI而不是通过普通的MVC控制器来完成简单的CRUD.诀窍是WebAPI应该是一个单独的解决方案(事实上,很可能是在不同的服务器/域上).

我怎么做？我错过了什么？是否只是设置路由指向WebAPI的服务器？我发现的所有示例都展示了如何使用MVC应用程序来使用WebAPI似乎假设WebAPI已经"融入"MVC应用程序,或者至少在同一台服务器上.

哦,澄清一下,我不是在谈论使用jQuery的Ajax调用......我的意思是MVC应用程序的控制器应该使用WebAPI来获取/放置数据.

Answer 1

您应该使用新的HttpClient来使用您的HTTP API.我还可以建议您完全异步调用.由于ASP.NET MVC控制器操作支持基于任务的异步编程模型,因此它非常强大且简单.

这是一个过于简化的例子.以下代码是示例请求的帮助程序类:

public class CarRESTService {

    readonly string uri = "http://localhost:2236/api/cars";

    public async Task<List<Car>> GetCarsAsync() {

        using (HttpClient httpClient = new HttpClient()) {

            return JsonConvert.DeserializeObject<List<Car>>(
                await httpClient.GetStringAsync(uri)    
            );
        }
    }
}

然后,我可以通过我的MVC控制器异步消耗它,如下所示:

public class HomeController : Controller {

    private CarRESTService service = new CarRESTService();

    public async Task<ActionResult> Index() {

        return View("index",
            await service.GetCarsAsync()
        );
    }
}

您可以查看下面的帖子,了解ASP.NET MVC的异步I/O操作的效果:

我在C#5.0和ASP.NET MVC Web应用程序中采用基于任务的异步编程

Answer 2

谢谢大家的回复.我认为@tugberk让我走上了正确的道路.这对我有用......

对于我的CarsRESTService助手:

public class CarsRESTService
{
    readonly string baseUri = "http://localhost:9661/api/cars/";

    public List<Car> GetCars()
    {
        string uri = baseUri;
        using (HttpClient httpClient = new HttpClient())
        {
            Task<String> response = httpClient.GetStringAsync(uri);
            return JsonConvert.DeserializeObjectAsync<List<Car>>(response.Result).Result;
        }
    }

    public Car GetCarById(int id)
    {
        string uri = baseUri + id;
        using (HttpClient httpClient = new HttpClient())
        {
            Task<String> response = httpClient.GetStringAsync(uri);
            return JsonConvert.DeserializeObjectAsync<Car>(response.Result).Result;
        }
    }
}

然后是CarsController.cs:

public class CarsController : Controller
{
    private CarsRESTService carsService = new CarsRESTService();

    //
    // GET: /Cars/

    public ActionResult Index()
    {
        return View(carsService.GetCars());
    }

    //
    // GET: /Cars/Details/5

    public ActionResult Details(int id = 0)
    {
        Car car = carsService.GetCarById(id);

        if (car == null)
        {
            return HttpNotFound();
        }
        return View(car);
    }
}

Answer 3

You can use WCF to consume the service. Like so:

[ServiceContract]
public interface IDogService
{
    [OperationContract]
    [WebGet(UriTemplate = "/api/dog")]
    IEnumerable<Dog> List();
}

public class DogServiceClient : ClientBase<IDogService>, IDogService
{
    public DogServiceClient(string endpointConfigurationName) : base(endpointConfigurationName)
    {
    }

    public IEnumerable<Dog> List()
    {
        return Channel.List();
    }
}

And then you can consume it in your controller:

public class HomeController : Controller
{
    public HomeController()
    {
    }

    public ActionResult List()
    {
        var service = new DogServiceClient("YourEndpoint");
        var dogs = service.List();
        return View(dogs);
    }
}

And in your web.config you place the configuration for your endpoint:

<system.serviceModel>
  <client>
    <endpoint address="http://localhost/DogService" binding="webHttpBinding"
    bindingConfiguration="" behaviorConfiguration="DogServiceConfig" 
    contract="IDogService" name="YourEndpoint" />
  </client>
  <behaviors>
    <endpointBehaviors>
      <behavior name="DogServiceConfig">
        <webHttp/>
      </behavior>
    </endpointBehaviors>
  </behaviors>
</system.serviceModel>