查看OData Versioning Sample 以获取入门知识。
问题的关键点通常是 DefaultHttpControllerSelector 按本地名称映射控制器，而不是全名/命名空间。
如果您的实体类型和控制器名称在两个 EdmModel 中都是唯一的，则您无需做任何特别的事情，它应该开箱即用。上面的示例利用了这个概念，强制您将字符串值注入控制器类的物理名称以使其唯一，然后在 ODataVersionControllerSelector 中覆盖 GetControllerName 以将传入路由映射到自定义控制器名称
如果控制器的唯一名称似乎很难，并且您更愿意使用完整的命名空间（这意味着您的控制器名称逻辑仍然是标准的），那么您当然可以实现自己的逻辑以在覆盖 @ 时选择特定的控制器类实例987654326@。只需覆盖 SelectController 即可。此方法将需要返回一个 HttpControllerDescriptor 的实例，这比示例涉及更多。
为了向您展示我的意思，我将发布一个旧项目需求的解决方案，这与您的有点不同。我有一个管理对多个数据库的访问的 WebAPI 项目，这些数据库具有相似的架构，许多实体名称相同，这意味着这些控制器类将具有相同的名称。控制器由文件夹/命名空间构成，因此有一个名为 DB 的根文件夹，然后每个数据库都有一个文件夹，然后控制器就在其中。
您可以看到该项目有许多不同的架构，它们有效地映射到不断发展的解决方案的版本，该图像中的非 DB 命名空间是 OData v4、v3 和标准 REST api 的混合。让所有这些野兽共存是可能的；）
此 HttpControllerSelector 覆盖检查运行时一次以缓存所有控制器类的列表，然后通过将路由前缀匹配到正确的控制器类来映射传入的路由请求。
/// <summary>
/// Customised controller for intercepting traffic for the DB Odata feeds.
/// Any route that is not prefixed with ~/DB/ will not be intercepted or processed via this controller
/// <remarks>Will instead be directed to the base class</remarks>
/// </summary>
public class DBODataHttpControllerSelector : DefaultHttpControllerSelector
{
private readonly HttpConfiguration _configuration;
public DBODataHttpControllerSelector(HttpConfiguration config)
: base(config)
{
_configuration = config;
}
// From: http://www.codeproject.com/Articles/741326/Introduction-to-Web-API-Versioning
private Dictionary<string, HttpControllerDescriptor> _controllerMap = null;
private List<string> _duplicates = new List<string>();
/// <summary>
/// Because we are interested in supporting nested namespaces similar to MVC "Area"s we need to
/// Index our available controller classes by the potential url segments that might be passed in
/// </summary>
/// <returns></returns>
private Dictionary<string, HttpControllerDescriptor> InitializeControllerDictionary()
{
if(_controllerMap != null)
return _controllerMap;
_controllerMap = new Dictionary<string, HttpControllerDescriptor>(StringComparer.OrdinalIgnoreCase);
// Create a lookup table where key is "namespace.controller". The value of "namespace" is the last
// segment of the full namespace. For example:
// MyApplication.Controllers.V1.ProductsController => "V1.Products"
IAssembliesResolver assembliesResolver = _configuration.Services.GetAssembliesResolver();
IHttpControllerTypeResolver controllersResolver = _configuration.Services.GetHttpControllerTypeResolver();
ICollection<Type> controllerTypes = controllersResolver.GetControllerTypes(assembliesResolver);
foreach (Type t in controllerTypes)
{
var segments = t.Namespace.Split(Type.Delimiter);
// For the dictionary key, strip "Controller" from the end of the type name.
// This matches the behavior of DefaultHttpControllerSelector.
var controllerName = t.Name.Remove(t.Name.Length - DefaultHttpControllerSelector.ControllerSuffix.Length);
var key = String.Format(CultureInfo.InvariantCulture, "{0}.{1}.{2}", segments[segments.Length - 2], segments[segments.Length - 1], controllerName);
// Check for duplicate keys.
if (_controllerMap.Keys.Contains(key))
{
_duplicates.Add(key);
}
else
{
_controllerMap[key] = new HttpControllerDescriptor(_configuration, t.Name, t);
}
}
// Remove any duplicates from the dictionary, because these create ambiguous matches.
// For example, "Foo.V1.ProductsController" and "Bar.V1.ProductsController" both map to "v1.products".
// CS: Ahem... thats why I've opted to go 3 levels of depth to key name, but this still applies if the duplicates are there again
foreach (string s in _duplicates)
{
_controllerMap.Remove(s);
}
return _controllerMap;
}
/// <summary>
/// Because we are interested in supporting nested namespaces we want the full route
/// to match to the full namespace (or at least the right part of it)
/// </summary>
/// <returns></returns>
private Dictionary<string, HttpControllerDescriptor> _fullControllerMap = null;
private Dictionary<string, HttpControllerDescriptor> InitializeFullControllerDictionary()
{
if(_fullControllerMap != null)
return _fullControllerMap;
_fullControllerMap = new Dictionary<string, HttpControllerDescriptor>(StringComparer.OrdinalIgnoreCase);
// Create a lookup table where key is "namespace.controller". The value of "namespace" is the last
// segment of the full namespace. For example:
// MyApplication.Controllers.V1.ProductsController => "V1.Products"
IAssembliesResolver assembliesResolver = _configuration.Services.GetAssembliesResolver();
IHttpControllerTypeResolver controllersResolver = _configuration.Services.GetHttpControllerTypeResolver();
ICollection<Type> controllerTypes = controllersResolver.GetControllerTypes(assembliesResolver);
foreach (Type t in controllerTypes)
{
var segments = t.Namespace.Split(Type.Delimiter);
// For the dictionary key, strip "Controller" from the end of the type name.
// This matches the behavior of DefaultHttpControllerSelector.
var controllerName = t.Name.Remove(t.Name.Length - DefaultHttpControllerSelector.ControllerSuffix.Length);
var key = t.FullName;// t.Namespace + "." + controllerName;
_fullControllerMap[key] = new HttpControllerDescriptor(_configuration, t.Name, t);
}
return _fullControllerMap;
}
/// <summary>
/// Select the controllers with a simulated MVC area sort of functionality, but only for the ~/DB/ route
/// </summary>
/// <param name="request"></param>
/// <returns></returns>
public override System.Web.Http.Controllers.HttpControllerDescriptor SelectController(System.Net.Http.HttpRequestMessage request)
{
string rootPath = "db";
IHttpRouteData routeData = request.GetRouteData();
string[] uriSegments = request.RequestUri.LocalPath.Split('/');
if (uriSegments.First().ToLower() == rootPath || uriSegments[1].ToLower() == rootPath)
{
#region DB Route Selector
// If we can find a known api and a controller, then redirect to the correct controller
// Otherwise allow the standard select to work
string[] knownApis = new string[] { "tms", "srg", "cumulus" };
// Get variables from the route data.
/* support version like this:
* config.Routes.MapODataRoute(
routeName: "ODataDefault",
routePrefix: "{version}/{area}/{controller}",
model: model);
object versionName = null;
routeData.Values.TryGetValue("version", out versionName);
object apiName = null;
routeData.Values.TryGetValue("api", out apiName);
object controllerName = null;
routeData.Values.TryGetValue("controller", out controllerName);
* */
// CS: we'll just use the local path AFTER the root path
// db/tms/contact
// db/srg/contact
// Implicity parse this as
// db/{api}/{controller}
// so [0] = ""
// so [1] = "api"
// so [2] = "version" (optional)
// so [2 or 3] = "controller"
if (uriSegments.Length > 3)
{
string apiName = uriSegments[2];
if (knownApis.Contains(string.Format("{0}", apiName).ToLower()))
{
string version = "";
string controllerName = uriSegments[3];
if (controllerName.ToLower().StartsWith("v")
// and the rest of the name is numeric
&& !controllerName.Skip(1).Any(c => !Char.IsNumber(c))
)
{
version = controllerName;
controllerName = uriSegments[4];
}
// if the route has an OData item selector (#) then this needs to be trimmed from the end.
if (controllerName.Contains('('))
controllerName = controllerName.Substring(0, controllerName.IndexOf('('));
string fullName = string.Format(CultureInfo.InvariantCulture, "{0}.{1}.{2}", apiName, version, controllerName).Replace("..", ".");
// Search for the controller.
// _controllerTypes is a list of HttpControllerDescriptors
var descriptors = InitializeControllerDictionary().Where(t => t.Key.EndsWith(fullName, StringComparison.OrdinalIgnoreCase)).ToList();
if (descriptors.Any())
{
var descriptor = descriptors.First().Value;
if (descriptors.Count > 1)
{
descriptor = null;
// Assume that the version was missing, and we have implemented versioning for that controller
// If there is a row with no versioning, so no v1, v2... then use that
// if all rows are versioned, use the highest version
if (descriptors.Count(d => d.Key.Split('.').Length == 2) == 1)
descriptor = descriptors.First(d => d.Key.Split('.').Length == 2).Value;
else if (descriptors.Count(d => d.Key.Split('.').Length > 2) == descriptors.Count())
descriptor = descriptors
.Where(d => d.Key.Split('.').Length > 2)
.OrderByDescending(d => d.Key.Split('.')[1])
.First().Value;
if (descriptor == null)
throw new HttpResponseException(
request.CreateErrorResponse(HttpStatusCode.InternalServerError,
"Multiple controllers were found that match this un-versioned request."));
}
if (descriptor != null)
return descriptor;
}
if (_duplicates.Any(d => d.ToLower() == fullName.ToLower()))
throw new HttpResponseException(
request.CreateErrorResponse(HttpStatusCode.InternalServerError,
"Multiple controllers were found that match this request."));
}
}
#endregion DB Route Selector
}
else
{
// match on class names that match the route.
// So if the route is odata.tms.testController
// Then the class name must also match
// Add in an option to doing a string mapping, so that
// route otms can mapp to odata.tms
// TODO: add any other custom logic for selecting the controller that you want, alternatively try this style syntax in your route config:
//routes.MapRoute(
// name: "Default",
// url: "{controller}/{action}/{id}",
// defaults: new { controller = "Home", action = "RegisterNow", id = UrlParameter.Optional },
// namespaces: new[] { "YourCompany.Controllers" }
//);
// Because controller path mapping might be controller/navigationproperty/action
// We need to check for the following matches:
// controller.navigationproperty.actionController
// controller.navigationpropertyController
// controllerController
string searchPath = string.Join(".", uriSegments).ToLower().Split('(')[0] + "controller";
var descriptors = InitializeFullControllerDictionary().Where(t => t.Key.ToLower().Contains(searchPath)).ToList();
if (descriptors.Any())
{
var descriptor = descriptors.First().Value;
if (descriptors.Count > 1)
{
descriptor = null;
// In this mode, I think we should only ever have a single match, ready to prove me wrong?
if (descriptor == null)
throw new HttpResponseException(
request.CreateErrorResponse(HttpStatusCode.InternalServerError,
"Multiple controllers were found that match this namespace request."));
}
if (descriptor != null)
return descriptor;
}
}
return base.SelectController(request);
}
}