MVC Api 的跨项目路由

 1 /// <summary>
 2     /// 自定义区域类
 3     /// </summary>
 4     public class CustomHttpControllerSelector: DefaultHttpControllerSelector
 5     {
 6         private const string NamespaceRouteVariableName = namespaceName";
 7 //namespaceName之后要用到
 8         //private const string AreaRouteVariableName = "area";
 9         private readonly HttpConfiguration _configuration;
10         private readonly Lazy<ConcurrentDictionary<string, Type>> _apiControllerCache;
11 
12         public CustomHttpControllerSelector(HttpConfiguration configuration)
13             : base(configuration)
14         {
15             _configuration = configuration;
16 
17             _apiControllerCache = new Lazy<ConcurrentDictionary<string, Type>>(
18                 new Func<ConcurrentDictionary<string, Type>>(InitializeApiControllerCache));
19         }
20 
21 
22         private ConcurrentDictionary<string, Type> InitializeApiControllerCache()
23         {
24             IAssembliesResolver assembliesResolver = this._configuration.Services.GetAssembliesResolver();
25             var types = this._configuration.Services.GetHttpControllerTypeResolver()
26                 .GetControllerTypes(assembliesResolver).ToDictionary(t => t.FullName, t => t);
27 
28             return new ConcurrentDictionary<string, Type>(types);
29         }
30 
31         public IEnumerable<string> GetControllerFullName(HttpRequestMessage request, string controllerName)
32         {
33             object namespaceName;
34             var data = request.GetRouteData();
35             IEnumerable<string> keys = _apiControllerCache.Value.ToDictionary<KeyValuePair<string, Type>, string, Type>(t => t.Key,
36                     t => t.Value, StringComparer.OrdinalIgnoreCase).Keys.ToList();
37 
38             if (!data.Values.TryGetValue(NamespaceRouteVariableName, out namespaceName))
39             {
40                 return from k in keys
41                        where k.EndsWith(string.Format(".{0}{1}", controllerName,
42                        DefaultHttpControllerSelector.ControllerSuffix), StringComparison.OrdinalIgnoreCase)
43                        select k;
44             }
45 
46             string[] namespaces = (string[])namespaceName;
47             return from n in namespaces
48                    join k in keys on string.Format("{0}.{1}{2}", n, controllerName,
49                    DefaultHttpControllerSelector.ControllerSuffix).ToLower() equals k.ToLower()
50                    select k;
51         }
52 
53 
54         public override HttpControllerDescriptor SelectController(HttpRequestMessage request)
55         {
56             Type type;
57             if (request == null)
58             {
59                 throw new ArgumentNullException("request");
60             }
61 
62             string controllerName = this.GetControllerName(request);
63             if (string.IsNullOrEmpty(controllerName))
64             {
65                 throw new HttpResponseException(request.CreateErrorResponse(HttpStatusCode.NotFound,
66                     string.Format("No route providing a controller name was found to match request URI ‘{0}‘",
67                     new object[] { request.RequestUri })));
68             }
69 
70             IEnumerable<string> fullNames = GetControllerFullName(request, controllerName);
71             if (fullNames.Count() == 0)
72             {
73                 throw new HttpResponseException(request.CreateErrorResponse(HttpStatusCode.NotFound,
74                         string.Format("No route providing a controller name was found to match request URI ‘{0}‘",
75                         new object[] { request.RequestUri })));
76             }
77 
78             if (!this._apiControllerCache.Value.TryGetValue(fullNames.First(), out type))
79             {
80                 throw new HttpResponseException(request.CreateErrorResponse(HttpStatusCode.NotFound,
81                         string.Format("No route providing a controller name was found to match request URI ‘{0}‘",
82                         new object[] { request.RequestUri })));
83             }
84 
85             return new HttpControllerDescriptor(_configuration, controllerName, type);
86         }
87     }