我有一种感觉，我正在做这个可怕的，可怕的错误。嵌套for循环？列出子类别的最佳实践方法是什么？我有一种感觉，它涉及在我的控制器动作中准备列表并通过一些动作结果发送给客户端，但我不知道从哪里开始？有人能指出我正确的方向吗？这是我的hacky代码：
<h2>Categories</h2>
<a href="javascript:;" onclick="newCategory()">Create New Category</a>
<br />
<ul class="parent">
<%foreach (var category in Model.Categories){%>
<%-- List all of the top-level parent categories --%>
<%if (category.IsParent && category.ParentId == 0)%>
<li>
<span class="buttons"><a href="javascript:;" onclick="editCategory(<%:category.CategoryId%>)" class="edit"></a> <a href="javascript:;" onclick="deleteCategory(<%:category.CategoryId%>)" class="delete"></a></span>
<span class="categoryName"><%:category.CategoryName%></span>
<span class="positionButtons"><%:Html.ActionLink(" ", "MoveCategoryUp", new {id = category.CategoryId},
new {Class = "moveUp"})%><%:Html.ActionLink(" ", "MoveCategoryDown", new {id = category.CategoryId},
new {Class = "moveDown"})%></span>
<%-- List all of the subs for each parent --%>
<ul>
<%-- Level 1 --%> <%foreach (var sub1 in Model.Categories){%>
<%if (sub1.ParentId == category.CategoryId){%>
<li>
<span class="buttons"><a href="javascript:;" onclick="editCategory(<%:sub1.CategoryId%>)" class="edit"></a> <a href="javascript:;" onclick="deleteCategory(<%:sub1.CategoryId%>)" class="delete"></a></span>
<span class="categoryName"><%:category.CategoryName%></span>
<span class="positionButtons"><%:Html.ActionLink(" ", "MoveCategoryUp", new {id = sub1.CategoryId},new {Class = "moveUp"})%><%:Html.ActionLink(" ", "MoveCategoryDown", new {id = sub1.CategoryId},new {Class = "moveDown"})%></span>
<%-- List all of the subs for each parent --%>
<%if (sub1.IsParent){%>
<ul>
<%-- Level 2 --%> <%foreach (var sub2 in Model.Categories){%>
<%if (sub2.ParentId == sub1.CategoryId){%>
<li>
<span class="buttons"><a href="javascript:;" onclick="editCategory(<%:sub2.CategoryId%>)" class="edit"></a> <a href="javascript:;" onclick="deleteCategory(<%:sub2.CategoryId%>)" class="delete"></a></span>
<span class="categoryName"><%:category.CategoryName%></span>
<span class="positionButtons"><%:Html.ActionLink(" ", "MoveCategoryUp", new {id = sub2.CategoryId},new {Class = "moveUp"})%><%:Html.ActionLink(" ", "MoveCategoryDown", new {id = sub2.CategoryId},new {Class = "moveDown"})%></span>
<%-- List all of the subs for each parent --%>
<%if (sub2.IsParent){%>
<ul>
<%-- Level 3 --%> <%foreach (var sub3 in Model.Categories){%>
<%if (sub3.ParentId == sub2.CategoryId){%>
<li>
<span class="buttons"><a href="javascript:;" onclick="editCategory(<%:sub3.CategoryId%>)" class="edit"></a> <a href="javascript:;" onclick="deleteCategory(<%:sub3.CategoryId%>)" class="delete"></a></span>
<span class="categoryName"><%:category.CategoryName%></span>
<span class="positionButtons"><%:Html.ActionLink(" ", "MoveCategoryUp",new {id = sub3.CategoryId},new {Class = "moveUp"})%><%:Html.ActionLink(" ", "MoveCategoryDown",new {id = sub3.CategoryId},new {Class = "moveDown"})%></span>
<%-- List all of the subs for each parent --%>
<%if (sub3.IsParent){%>
<ul>
<%-- Level 4 --%> <%foreach (var sub4 in Model.Categories){%>
<%if (sub4.ParentId == sub3.CategoryId){%>
<li>
<span class="buttons"><a href="javascript:;" onclick="editCategory(<%:sub4.CategoryId%>)" class="edit"></a> <a href="javascript:;" onclick="deleteCategory(<%:sub4.CategoryId%>)" class="delete"></a></span>
<span class="categoryName"><%:category.CategoryName%></span>
<span class="positionButtons"><%:Html.ActionLink(" ", "MoveCategoryUp", new {id = sub4.CategoryId}, new {Class = "moveUp"})%><%:Html.ActionLink(" ", "MoveCategoryDown", new {id = sub4.CategoryId}, new {Class = "moveDown"})%></span>
<%-- If more than 4 levels of subcategories are required, put another level here --%>
</li>
<%}%>
<%}%>
</ul>
<%}%>
</li>
<%}%>
<%}%>
</ul>
<%}%>
</li>
<%}%>
<%}%>
</ul>
<%}%>
</li>
<%}%>
<%}%>
</ul>
</li>
<%}%>
</ul>
修改
不幸的是，这段代码没有呈现我正在寻找的结果，所以我真的不能提供更多：http://jsfiddle.net/EeaGr/每个列表项都有用于编辑/删除的按钮和用于其类别的moveup / movedown选项。我的类别具有以下属性：
CategoryID：int
名称：字符串
ParentID：int
IsParent：bool
职位：int
答案 0 :(得分：6)
首先，我会更改类别的结构，以便每个Category都有Subcategories属性。
然后，你应该创建一个用户控件来呈现一个Category，如果该类别有子类别，它会递归调用自己：
<强> CategoryControl.ascx ：
<%@ Control Language="C#" Inherits="System.Web.Mvc.ViewUserControl<Category>" %>
<%@ Import Namespace="so_subcats.Model" %>
<li><%= Model.Name %>
<% if (Model.Subcategories != null) { %>
<ul>
<% foreach (Category subcat in Model.Subcategories)
Html.RenderPartial("CategoryControl", subcat); %>
</ul>
<% } %>
</li>
然后只需创建一个View，为每个顶级类别呈现此控件：
<强> Categories.aspx ：
<%@ Page Title="" Language="C#" MasterPageFile="~/Views/Shared/Site.Master"
Inherits="System.Web.Mvc.ViewPage<IEnumerable<Category>>" %>
<%@ Import Namespace="so_subcats.Model" %>
<asp:Content ID="Content1" ContentPlaceHolderID="TitleContent" runat="server">
Categories
</asp:Content>
<asp:Content ID="Content2" ContentPlaceHolderID="MainContent" runat="server">
<h2>Categories</h2>
<ul>
<% foreach (Category cat in Model)
Html.RenderPartial("CategoryControl", cat); %>
</ul>
</asp:Content>
当然，如果您不想更改类的结构，也可以使用此解决方案，只需稍微修改它。