少なくとも1つを選択しない場合、モデル検証はリストボックス値にリンクされた属性を評価しません。この方法では、必要な値を通知するためにDataAnnotationsを使用してモデル評価を行うことはできません。
コントローラー：
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
using TestValidation.Models;
namespace TestValidation.Controllers
{
[HandleError]
public class HomeController : Controller
{
private SelectList list = new SelectList(new List<string>()
{
"Sao Paulo",
"Toronto",
"New York",
"Vancouver"
});
public ActionResult Index()
{
ViewData["ModelState"] = "NOT EVAL";
ViewData["ItemsList"] = list;
return View();
}
[AcceptVerbs(HttpVerbs.Post)]
public ActionResult Index(MyEntity entity)
{
if (ModelState.IsValid)
{
ViewData["ModelState"] = "VALID";
}
else
{
ViewData["ModelState"] = "NOT VALID!!!";
}
ViewData["ItemsList"] = list;
return View();
}
public ActionResult About()
{
return View();
}
}
}
景色：
<%@ Page Language="C#" MasterPageFile="~/Views/Shared/Site.Master" Inherits="System.Web.Mvc.ViewPage<TestValidation.Models.MyEntity>" %>
<asp:Content ID="indexTitle" ContentPlaceHolderID="TitleContent" runat="server">
Home Page
</asp:Content>
<asp:Content ID="indexContent" ContentPlaceHolderID="MainContent" runat="server">
<h2>
Validation Test</h2>
<p>
<% using (Html.BeginForm())
{%>
<fieldset>
<p>
ModelState:
<%= Html.Encode((string)ViewData["ModelState"])%>
</p>
<p>
<label for="Name">
Name:</label>
<%= Html.TextBoxFor(m => m.Name)%>
<%= Html.ValidationMessageFor(m => m.Name)%>
</p>
<p>
<label for="ItemFromList">
Items (list):</label>
<%= Html.ListBoxFor(m => m.ItemFromList, ViewData["ItemsList"] as SelectList)%>
<%= Html.ValidationMessageFor(m => m.ItemFromList)%>
</p>
<p>
<label for="ItemFromCombo">
Items (combo):</label>
<%= Html.DropDownListFor(m => m.ItemFromCombo, ViewData["ItemsList"] as SelectList)%>
<%= Html.ValidationMessageFor(m => m.ItemFromCombo)%>
</p>
<p>
<input type="submit" value="Submit" />
</p>
</fieldset>
<% } %>
</asp:Content>
モデル：
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.ComponentModel.DataAnnotations;
namespace TestValidation.Models
{
public class MyEntity_Validate : ValidationAttribute
{
public MyEntity_Validate()
{
this.ErrorMessage = "Validated!. Is <> Toronto";
}
public override bool IsValid(object value)
{
return ((string)value == "Toronto");
}
}
public class MyEntity
{
[Required]
public string Name { get; set; }
[MyEntity_Validate]
public string ItemFromList { get; set; }
[MyEntity_Validate]
public string ItemFromCombo { get; set; }
}
}
どんな助けでも大歓迎です。ありがとうございました。