小编sam*_*sam的帖子

当我遇到这个问题时,我正在观看Pluralsight 的教程:搜索这个网站并发现(简单的注入器无法在Web API控制器中注入依赖关系,确保控制器具有无参数的公共构造函数错误)不同的解决方案,但他们没有工作要么.使用WebApi和Ninject时遇到同样的问题,作者在编写代码时没有做任何事情,不知道为什么我要面对这个问题,如果有人解释原因以及解决方案(写什么和写什么),将会很感激.这是代码:

//NinjectWebCommon.cs
 private static void RegisterServices(IKernel kernel)
    {
        kernel.Bind<IRepository>().To<Repository>().InRequestScope(); //for making singleton
        kernel.Bind<WebAPIandEFContext>().To<WebAPIandEFContext>().InRequestScope();

    }   
//Order Controller
  public class OrderController : ApiController
{
    private IRepository _repo;


    public OrderController(IRepository repo) 
    {
        _repo = repo;
    }
//remaining code....
ERROR description
{"$id":"1","Message":"An error has occurred.","ExceptionMessage":"An error 

occurred when trying to create a controller of type 'OrderController'. Make sure that the controller has a parameterless public constructor.","ExceptionType":"System.InvalidOperationException","StackTrace":"   at System.Web.Http.Dispatcher.DefaultHttpControllerActivator.Create(HttpRequestMessage request, HttpControllerDescriptor controllerDescriptor, Type controllerType)\r\n   at System.Web.Http.Controllers.HttpControllerDescriptor.CreateController(HttpRequestMessage request)\r\n …

我有一个角色对象,我想使用PrimeNG映射到TreeNode对象,以在树中显示它.角色对象是这样的(如图所示)

role: [
id: ....
name: ....
   description: ....
   roles[]: .....
]

树节点对象具有以下结构:

{
"data": 
[
    {
        "label": "Documents",
        "data": "Documents Folder",
        "expandedIcon": "fa-folder-open",
        "collapsedIcon": "fa-folder",
        "children": [{
                "label": "Work",
                "data": "Work Folder",
                "expandedIcon": "fa-folder-open",
                "collapsedIcon": "fa-folder",
                "children": [{"label": "Expenses.doc", "icon": "fa-file-word-o", "data": "Expenses Document"}, {"label": "Resume.doc", "icon": "fa-file-word-o", "data": "Resume Document"}]
            },
            {
                "label": "Home",
                "data": "Home Folder",
                "expandedIcon": "fa-folder-open",
                "collapsedIcon": "fa-folder",
                "children": [{"label": "Invoices.txt", "icon": "fa-file-word-o", "data": "Invoices for this month"}]
            }]
    },
    {
        "label": "Pictures",
        "data": "Pictures …