System.MissingMethodException：为此对象定义的无参数构造函数

Question

'/'应用程序中的服务器错误。

没有为此对象定义的无参数构造函数。

描述：执行当前Web请求期间发生未处理的异常。请查看堆栈跟踪以获取有关该错误的更多信息以及源代码的位置。

异常详细信息：System.MissingMethodException：没有为此对象定义的无参数构造函数。

源错误：

在当前web请求的执行过程中生成未处理的异常。关于异常的来源和位置的信息可以使用下面的异常堆栈跟踪来标识。

堆栈跟踪：

[MissingMethodException: No parameterless constructor defined for this object.] 
    System.RuntimeTypeHandle.CreateInstance(RuntimeType type, Boolean publicOnly, Boolean noCheck, Boolean& canBeCached, RuntimeMethodHandleInternal& ctor, Boolean& bNeedSecurityCheck) +0 
    System.RuntimeType.CreateInstanceSlow(Boolean publicOnly, Boolean skipCheckThis, Boolean fillCache) +98 
    System.RuntimeType.CreateInstanceDefaultCtor(Boolean publicOnly, Boolean skipVisibilityChecks, Boolean skipCheckThis, Boolean fillCache) +241 
    System.Activator.CreateInstance(Type type, Boolean nonPublic) +69 
    System.Web.Mvc.DefaultModelBinder.CreateModel(ControllerContext controllerContext, ModelBindingContext bindingContext, Type modelType) +199 
    System.Web.Mvc.DefaultModelBinder.BindComplexModel(ControllerContext controllerContext, ModelBindingContext bindingContext) +572 
    System.Web.Mvc.DefaultModelBinder.BindModel(ControllerContext controllerContext, ModelBindingContext bindingContext) +454 
    System.Web.Mvc.ControllerActionInvoker.GetParameterValue(ControllerContext controllerContext, ParameterDescriptor parameterDescriptor) +317 
    System.Web.Mvc.ControllerActionInvoker.GetParameterValues(ControllerContext controllerContext, ActionDescriptor actionDescriptor) +117 
    System.Web.Mvc.Async.<>c__DisplayClass25.<BeginInvokeAction>b__1e(AsyncCallback asyncCallback, Object asyncState) +476 
    System.Web.Mvc.Async.WrappedAsyncResult`1.Begin(AsyncCallback callback, Object state, Int32 timeout) +124 
    System.Web.Mvc.Async.AsyncControllerActionInvoker.BeginInvokeAction(ControllerContext controllerContext, String actionName, AsyncCallback callback, Object state) +304 
    System.Web.Mvc.<>c__DisplayClass1d.<BeginExecuteCore>b__17(AsyncCallback asyncCallback, Object asyncState) +30 
    System.Web.Mvc.Async.WrappedAsyncResult`1.Begin(AsyncCallback callback, Object state, Int32 timeout) +124 
    System.Web.Mvc.Controller.BeginExecuteCore(AsyncCallback callback, Object state) +389 
    System.Web.Mvc.Async.WrappedAsyncResult`1.Begin(AsyncCallback callback, Object state, Int32 timeout) +124 
    System.Web.Mvc.Controller.BeginExecute(RequestContext requestContext, AsyncCallback callback, Object state) +319 
    System.Web.Mvc.Controller.System.Web.Mvc.Async.IAsyncController.BeginExecute(RequestContext requestContext, AsyncCallback callback, Object state) +15 
    System.Web.Mvc.<>c__DisplayClass8.<BeginProcessRequest>b__2(AsyncCallback asyncCallback, Object asyncState) +76 
    System.Web.Mvc.Async.WrappedAsyncResult`1.Begin(AsyncCallback callback, Object state, Int32 timeout) +124 
    System.Web.Mvc.MvcHandler.BeginProcessRequest(HttpContextBase httpContext, AsyncCallback callback, Object state) +251 
    System.Web.Mvc.MvcHandler.BeginProcessRequest(HttpContext httpContext, AsyncCallback callback, Object state) +50 
    System.Web.Mvc.MvcHandler.System.Web.IHttpAsyncHandler.BeginProcessRequest(HttpContext context, AsyncCallback cb, Object extraData) +16 
    System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +8969412 
    System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +184 

Answer 1

检查行动参数，参数的类型的一个没有默认构造函数，那为什么MVC不能绑定。

Answer 2

问题在这里回答：Server Error in '/' Application. No parameterless constructor defined for this object。

Probabaly传递给您的请求的视图模型的成员之一没有无参数的构造函数。

Answer 3

private ISupplierRepository _supplierRepository; 
public SupplierController() 
     : this(new SupplierRepository()) 
     { 
     } 
     public SupplierController(ISupplierRepository repository) 
     { 
      _supplierRepository = repository; 
     }