ASP.NET MVC扩展带验证的单选按钮_实用技巧_

using System.Collections.Generic; using System.Linq.Expressions; using System.Text; using System.Web.Mvc.Html; namespace System.Web.Mvc { public static class HtmlExtensions { public static MvcHtmlString RadioButtonListFor(this HtmlHelper htmlHelper, Expression> expression, IEnumerable list) { //获取元数据 var metaData = ModelMetadata.FromLambdaExpression(expression, htmlHelper.ViewData); var sb = new StringBuilder(); if (list != null) { foreach (var item in list) { //把属性名和集合元素的Value值拼接作为元素的id var id = string.Format("{0}_{1}", metaData.PropertyName, item.Value); //创建单选按钮 var label = htmlHelper.Label(id, HttpUtility.HtmlEncode(item.Text)); var radio = htmlHelper.RadioButtonFor(expression, item.Value, new {id = id}).ToHtmlString(); sb.AppendFormat("
{0}{1}
", radio, label); } } return MvcHtmlString.Create(sb.ToString()); } } }

using System.ComponentModel.DataAnnotations; namespace MvcApplication1.Models { public class Vm { [Required(ErrorMessage = "必填")] public int CityId { get; set; } } }

namespace MvcApplication1.Models { public class City { public int Id { get; set; } public string Name { get; set; } } }

using System.Collections.Generic; using System.Linq; using System.Web.Mvc; using MvcApplication1.Models; namespace MvcApplication1.Controllers { public class HomeController : Controller { public ActionResult Index() { List cities = new List() { new City(){Id = 1, Name = "青岛"}, new City(){Id = 2, Name = "济南"}, new City(){Id = 3, Name = "平度"} }; ViewData["c"] = from c in cities select new SelectListItem() {Text = c.Name, Value = c.Id.ToString()}; return View(new Vm()); } [HttpPost] public ActionResult Index(Vm vm) { if (ModelState.IsValid) { return Content(vm.CityId.ToString()); } else { return View(vm); } } } }

 @Styles.Render("~/Content/css") @Scripts.Render("~/bundles/jquery") @Scripts.Render("~/bundles/jqueryval")  @RenderBody() @RenderSection("scripts", required: false) 

@model MvcApplication1.Models.Vm @{ ViewBag.Title = "Index"; Layout = "~/Views/Shared/_Layout.cshtml"; }  @using (Html.BeginForm("Index", "Home", FormMethod.Post, new {id = "addForm"})) { @Html.RadioButtonListFor(v => v.CityId, ViewData["c"] as IEnumerable) @Html.ValidationMessageFor(v => v.CityId)  }