如何在C#UWP应用程序中使用ASP.NET Core WebAPI？

Question

我试图了解如何在UWP/UAP应用程序中使用ASP.NET Core WebAPI.我以为我可以使用类似于使用WCF服务的WebAPI,但我还没有找到任何相关内容.

此外,我尝试安装Microsoft.AspNet.WebApi.Core但没有成功,因为它与UAP(版本= V10.0)不兼容.

我现在有点迷失了.也许有人可以告诉我如何在UWP应用程序中使用WebApi.

Answer 1

这与使用任何API调用相同.只需使用HttpClient该类调用端点并处理响应,预期行为没有区别.

想象一下,您有一个如下定义的ASP.NET Core Web API端点:

public class StackoverflowController : Controller
{    
    // I wanted to exemplify async capabilities.
    // You'd use async/await for getting database values, etc.
    [
        HttpGet,
        AllowAnonymous,
        Route("api/greeting")
    ]
    public Task<GreetingResult> Greeting() =>
        Task.FromResult(new GreetingResult { Message = "Hello world!" });
}

public class GreetingResult
{
    public string Message { get; set; }
}

假设它托管在`localhost:5000'上,您可以执行以下操作:

public class Consumer
{
    public async Task<string> GetGreetingAsync()
    {
        using (var client = new HttpClient())
        {
            var response = 
                await client.GetStringAsync("http://localhost:5000/api/greeting");
            // The response object is a string that looks like this:
            // "{ message: 'Hello world!' }"
        }
    }
}

此外,您可以将此反序列化为强类型对象使用Newtonsoft.Json.我有一个我的UWP应用程序在这里做这件事的例子.

Answer 2

我将添加更多信息:

在UWP中使用Web Api的最佳方法是使用前面提到的HttpClient.

以下是我认为可能有用的一些示例.

最好的做法是创建MobileServiceClient类,您可以在其中收集可在Web Api级别执行的所有操作:

public class MobileServiceClient
{
    //access token if you use authentication:
    private string _accessToken;
    //address of your Web Api:
    private string _serviceAddress;

    //Constructor:
    public MobileServiceClient(string accessToken, string serviceAddress)
    {
        _accessToken = accessToken;
        _serviceAddress = serviceAddress;
    }

//Now you can implement methods that you will invoke to perform selected operation related with Web Api:

#region Methods

//You can perform "Get" to retrieve object from the Web Api and then deserialize it (using Json .NET):

public async Task<SampleClass> GetSampleClass()
    {
        SampleClass sampleClass= null;
        try
        {
            using (HttpClient client = new HttpClient())
            {
                client.DefaultRequestHeaders.Add("Authorization", "Bearer " + _accessToken);
                var data = await client.GetAsync(string.Concat(_serviceAddress, "routeName"));
                var jsonResponse = await data.Content.ReadAsStringAsync();
                if (jsonResponse != null)
                    sampleClass= JsonConvert.DeserializeObject<SampleClass>(jsonResponse);
                return sampleClass;
            }
        }

        catch (WebException exception)
        {
            throw new WebException("An error has occurred while calling GetSampleClass method: " + exception.Message);
        }
    }

//You can perform "Get" to retrieve list of objects and then deserialize it:

public async Task<List<SampleClass>> GetSampleClassObjects()
    {
        List<SampleClass> SampleClassObjectsList = null;
        try
        {
            using (HttpClient client = new HttpClient())
            {
                client.DefaultRequestHeaders.Add("Authorization", "Bearer " + _accessToken);
                var data = await client.GetAsync(string.Concat(_serviceAddress, "routeName"));
                var jsonResponse = await data.Content.ReadAsStringAsync();
                if (jsonResponse != null)
                    SampleClassObjectsList = JsonConvert.DeserializeObject<List<SampleClass>>(jsonResponse);
                return SampleClassObjectsList;
            }
        }

        catch (WebException exception)
        {
            throw new WebException("An error has occurred while calling GetSampleClassObjects method: " + exception.Message);
        }
    }

//You can also "Post" some object:

public async Task<bool> PostSomeObject(SampleClass sampleClassObject)
    {
        try
        {
            using (HttpClient client = new HttpClient())
            {
                var sampleClassObjectJson = JsonConvert.SerializeObject(sampleClassObject);
                client.DefaultRequestHeaders.Add("Authorization", "Bearer " + _accessToken);
                var content = new StringContent(sampleClassObjectJson, Encoding.UTF8, "application/json");
                HttpResponseMessage response = await client.PostAsync(string.Concat(_serviceAddress + "routeName"), content);
                if (response.StatusCode == HttpStatusCode.OK)
                    return true;
                else
                    throw new WebException("An error has occurred while calling PostSomeObject method: " + response.Content);
            }
        }

        catch (WebException exception)
        {
            throw new WebException("An error has occurred while calling PostFeedback method: " + exception.Message);
        }
    }
#endregion
}

请注意,如果您决定支持其他平台(如Xamarin Android或iOS),通过此类实施,您可以在将来共享代码.我希望这能帮到您.