using System.IO;
using System.Threading.Tasks;namespace CognitiveMiddlewareService.CognitiveServices
{public interface IVisionService{Task<Landmark> RecognizeLandmarkAsync(Stream imgStream);Task<Celebrity> RecognizeCelebrityAsync(Stream imgStream);}
}VisionService.cs - 访问影像服务的逻辑代码using Newtonsoft.Json;
using System;
using System.IO;
using System.Net.Http;
using System.Net.Http.Headers;
using System.Threading.Tasks;namespace CognitiveMiddlewareService.CognitiveServices
{public class VisionService : IVisionService{const string LandmarkEndpoint = "https://eastasia.api.cognitive.microsoft.com/vision/v2.0/models/landmarks/analyze";const string CelebrityEndpoint = "https://eastasia.api.cognitive.microsoft.com/vision/v2.0/models/celebrities/analyze";const string Key1 = "0e290876aed45d69f6fb97bb621f71";const string Key2 = "9799f09b87e4be6b2be132309b8e57";private readonly IHttpClientFactory httpClientFactory;public VisionService(IHttpClientFactory cf){this.httpClientFactory = cf;}public async Task<Landmark> RecognizeLandmarkAsync(Stream imgStream){VisionResult result = await this.MakePostRequest(LandmarkEndpoint, imgStream);if (result?.result?.landmarks?.Length > 0){return result?.result?.landmarks[0];}return null;}public async Task<Celebrity> RecognizeCelebrityAsync(Stream imgStream){VisionResult result = await this.MakePostRequest(CelebrityEndpoint, imgStream);if (result?.result?.celebrities?.Length > 0){return result?.result?.celebrities[0];}return null;}private async Task<VisionResult> MakePostRequest(string uri, Stream imageStream){try{using (HttpClient httpClient = httpClientFactory.CreateClient()){using (StreamContent streamContent = new StreamContent(imageStream)){streamContent.Headers.ContentType = new MediaTypeHeaderValue("application/octet-stream");using (var request = new HttpRequestMessage(HttpMethod.Post, uri)){request.Content = streamContent;request.Headers.Add("Ocp-Apim-Subscription-Key", Key1);using (HttpResponseMessage response = await httpClient.SendAsync(request)){if (response.IsSuccessStatusCode){string resultString = await response.Content.ReadAsStringAsync();VisionResult result = JsonConvert.DeserializeObject<VisionResult>(resultString);return result;}else{}}}return null;}}}catch (Exception ex){return null;}}}
}

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;namespace CognitiveMiddlewareService.CognitiveServices
{public class VisionResult{public Result result { get; set; }public string requestId { get; set; }}public class Result{public Landmark[] landmarks { get; set; }public Celebrity[] celebrities { get; set; }}public class Landmark{public string name { get; set; }public double confidence { get; set; }}public class Celebrity{public virtual string name { get; set; }public virtual double confidence { get; set; }}
}

using System.Threading.Tasks;namespace CognitiveMiddlewareService.CognitiveServices
{public interface IEntitySearchService{Task<string> SearchEntityAsync(string query);}
}

using System.Diagnostics;
using System.Net.Http;
using System.Threading.Tasks;namespace CognitiveMiddlewareService.CognitiveServices
{public class EntitySearchService : IEntitySearchService{const string SearchEntityEndpoint = "https://api.cognitive.microsoft.com/bing/v7.0/entities?mkt=en-US&q=";const string Key1 = "a0be81df8ad449481492a11107645b";const string Key2 = "0803e4673824f9abb7487d8c3db6dd";private readonly IHttpClientFactory httpClientFactory;public EntitySearchService(IHttpClientFactory cf){this.httpClientFactory = cf;}public async Task<string> SearchEntityAsync(string query){using (HttpClient hc = this.httpClientFactory.CreateClient()){string uri = SearchEntityEndpoint + query;string jsonResult = await Helper.MakeGetRequest(hc, uri, Key1);Debug.Write(jsonResult);return jsonResult;}}}
}

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;namespace CognitiveMiddlewareService.CognitiveServices
{public class EntityResult{public string _type { get; set; }public Querycontext queryContext { get; set; }public Entities entities { get; set; }public Rankingresponse rankingResponse { get; set; }}public class Querycontext{public string originalQuery { get; set; }}public class Entities{public Value[] value { get; set; }}public class Value{public string id { get; set; }public Contractualrule[] contractualRules { get; set; }public string webSearchUrl { get; set; }public string name { get; set; }public string url { get; set; }public Image image { get; set; }public string description { get; set; }public Entitypresentationinfo entityPresentationInfo { get; set; }public string bingId { get; set; }}public class Image{public string name { get; set; }public string thumbnailUrl { get; set; }public Provider[] provider { get; set; }public string hostPageUrl { get; set; }public int width { get; set; }public int height { get; set; }public int sourceWidth { get; set; }public int sourceHeight { get; set; }}public class Provider{public string _type { get; set; }public string url { get; set; }}public class Entitypresentationinfo{public string entityScenario { get; set; }public string[] entityTypeHints { get; set; }}public class Contractualrule{public string _type { get; set; }public string targetPropertyName { get; set; }public bool mustBeCloseToContent { get; set; }public License license { get; set; }public string licenseNotice { get; set; }public string text { get; set; }public string url { get; set; }}public class License{public string name { get; set; }public string url { get; set; }}public class Rankingresponse{public Sidebar sidebar { get; set; }}public class Sidebar{public Item[] items { get; set; }}public class Item{public string answerType { get; set; }public int resultIndex { get; set; }public Value1 value { get; set; }}public class Value1{public string id { get; set; }}}

using Microsoft.AspNetCore.Http;
using System;
using System.IO;
using System.Net.Http;
using System.Threading.Tasks;namespace CognitiveMiddlewareService.CognitiveServices
{public class Helper{public static byte[] GetBuffer(IFormFile formFile){Stream stream = formFile.OpenReadStream();MemoryStream memoryStream = new MemoryStream();formFile.CopyTo(memoryStream);var buffer = memoryStream.GetBuffer();return buffer;}public static MemoryStream GetStream(byte[] buffer){if (buffer == null){return null;}return new MemoryStream(buffer, false);}public static async Task<string> MakeGetRequest(HttpClient httpClient, string uri, string key){try{using (var request = new HttpRequestMessage(HttpMethod.Get, uri)){request.Headers.Add("Ocp-Apim-Subscription-Key", key);using (HttpResponseMessage response = await httpClient.SendAsync(request)){if (response.IsSuccessStatusCode){string jsonResult = await response.Content.ReadAsStringAsync();return jsonResult;}}}return null;}catch (Exception ex){return null;}}}
}