页面指令中出现奇怪的运行时错误

Here is the page directive:

这是页面指令：

<%@ Page Title="Edit Condition" Language="C#" MasterPageFile="~/Site.Master" AutoEventWireup="true" CodeBehind="ManageCondition.aspx.cs" Inherits="Backyard_Cures.ManageCondition" %>
<%@ Pag