asp.net-mvc - 已添加具有相同 key 的项目

Question

每当我提交表单时，我都会收到此错误，而且操作方法也不会被调用，因为:

An item with the same key has already been added.

以及异常详细信息:

[ArgumentException: An item with the same key has already been added.]
System.ThrowHelper.ThrowArgumentException(ExceptionResource resource) +52
System.Collections.Generic.Dictionary`2.Insert(TKey key, TValue value, Boolean add) +9382923 System.Linq.Enumerable.ToDictionary(IEnumerable`1 source, Func`2 keySelector, Func`2 elementSelector, IEqualityComparer`1 comparer) +252
System.Linq.Enumerable.ToDictionary(IEnumerable`1 source, Func`2 keySelector, IEqualityComparer`1 comparer) +91
System.Web.Mvc.ModelBindingContext.get_PropertyMetadata() +228 System.Web.Mvc.DefaultModelBinder.BindProperty(ControllerContext controllerContext, ModelBindingContext bindingContext, PropertyDescriptor propertyDescriptor) +392
System.Web.Mvc.DefaultModelBinder.BindProperties(ControllerContext controllerContext, ModelBindingContext bindingContext) +147
System.Web.Mvc.DefaultModelBinder.BindComplexElementalModel(ControllerContext controllerContext, ModelBindingContext bindingContext, Object model) +98
System.Web.Mvc.DefaultModelBinder.BindComplexModel(ControllerContext controllerContext, ModelBindingContext bindingContext) +2504
System.Web.Mvc.DefaultModelBinder.BindModel(ControllerContext controllerContext, ModelBindingContext bindingContext) +548
System.Web.Mvc.ControllerActionInvoker.GetParameterValue(ControllerContext controllerContext, ParameterDescriptor parameterDescriptor) +473
System.Web.Mvc.ControllerActionInvoker.GetParameterValues(ControllerContext controllerContext, ActionDescriptor actionDescriptor) +181
System.Web.Mvc.ControllerActionInvoker.InvokeAction(ControllerContext controllerContext, String actionName) +830 System.Web.Mvc.Controller.ExecuteCore() +136 System.Web.Mvc.ControllerBase.Execute(RequestContext requestContext) +111
System.Web.Mvc.ControllerBase.System.Web.Mvc.IController.Execute(RequestContext requestContext) +39
System.Web.Mvc.<>c__DisplayClass8.b__4() +65 System.Web.Mvc.Async.<>c__DisplayClass1.b__0() +44 System.Web.Mvc.Async.<>c__DisplayClass8`1.b__7(IAsyncResult _) +42 System.Web.Mvc.Async.WrappedAsyncResult`1.End() +141 System.Web.Mvc.Async.AsyncResultWrapper.End(IAsyncResult asyncResult, Object tag) +54
System.Web.Mvc.Async.AsyncResultWrapper.End(IAsyncResult asyncResult, Object tag) +40
System.Web.Mvc.MvcHandler.EndProcessRequest(IAsyncResult asyncResult) +52
System.Web.Mvc.MvcHandler.System.Web.IHttpAsyncHandler.EndProcessRequest(IAsyncResult result) +38
System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +8836913 System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +184

查看页面

<%@ Page Title="" Language="C#" MasterPageFile="~/Views/Shared/XYZ.Master"
    Inherits="System.Web.Mvc.ViewPage<XYZ.Models.Admin.AdminSegmentCommissionsModel>" %>
    <asp:Content ID="Content1" ContentPlaceHolderID="TitleContent" runat="server">
        Create
    </asp:Content>
    <asp:Content ID="Content2" ContentPlaceHolderID="MainContent" runat="server">
        <% using (Html.BeginForm()) {%>    
            <div class="box3">
                <div class="userinfo">
                    <h3>Admin Segment Commissions</h3>
                </div>
                <div class="buttons-panel">
                    <ul>
                       <li>
                           <input type="submit" value="Save" class="save" />
                       </li>
                       <li>
                           <%:Html.ActionLink("Cancel", "Index", new { controller = "AdminSegmentCommissions" }, new { @class = "cancel" })%>
                           <%--<input type="button" value="Cancel" class="cancel" onclick="document.location.href='/AirlineLedgerTransactionReceiver/Index'" />--%>
                       </li>
                   </ul>
               </div>
           </div>
           <div class="row-1">
               <div class="form-box1 round-corner">
                   <div class="form-box1-row">
                       <div class="form-box1-row-content float-left">
                           <div>
                               <label>
                                   <%: Html.LabelFor(model => model.FromSegmentNumber) %></label>
                                   <%: Html.TextBoxFor(model => model.FromSegmentNumber) %>
                                   <%: Html.ValidationMessageFor(model => model.FromSegmentNumber) %>
                          </div>
                      </div>
                  </div>
              </div>
          </div>
      <%} %>

Answer 1

很可能，您的模型两次包含相同的属性。也许您正在使用 new 来隐藏基本属性。

解决方案是覆盖该属性或使用其他名称。

如果您分享您的模型，我们将能够详细说明。