ASP.NET MVC使用Session会话保持表单状态_实用技巧_

using System.ComponentModel.DataAnnotations; namespace MvcApplication1.Models { public class Player { public int Id { get; set; } [Required(ErrorMessage = "必填")] [Display(Name = "球员名称")] public string Name { get; set; } } }

using System.Collections.Generic; using System.ComponentModel.DataAnnotations; namespace MvcApplication1.Models { public class Club { public Club() { this.Players = new List(); } public int Id { get; set; } [Required(ErrorMessage = "必填")] [Display(Name = "俱乐部名称")] public string Name { get; set; } public List Players { get; set; } } }

@model MvcApplication1.Models.Club @{ ViewBag.Title = "Index"; Layout = "~/Views/Shared/_Layout.cshtml"; } 
Index
 @using (Html.BeginForm("Index", "Home", FormMethod.Post, new {id = "myForm"})) { @Html.LabelFor(m => m.Name) @Html.TextBoxFor(m => m.Name) @Html.ValidationMessageFor(m => m.Name) 

 @if (Model.Players != null) { foreach (var item in Model.Players) { Html.RenderAction("NewPlayerRow", "Home", new { player = @item }); } } 
添加球员

到别的地方转转   
 } @section scripts {  }

//对动态生成内容客户端验证 (function ($) { $.validator.unobtrusive.parseDynamicContent = function (selector, formSelector) { $.validator.unobtrusive.parse(selector); var form = $(formSelector); var unobtrusiveValidation = form.data('unobtrusiveValidation'); var validator = form.validate(); $.each(unobtrusiveValidation.options.rules, function (elname, elrules) { if (validator.settings.rules[elname] == undefined) { var args = {}; $.extend(args, elrules); args.messages = unobtrusiveValidation.options.messages[elname]; //edit:use quoted strings for the name selector $("[name='" + elname + "']").rules("add", args); } else { $.each(elrules, function (rulename, data) { if (validator.settings.rules[elname][rulename] == undefined) { var args = {}; args[rulename] = data; args.messages = unobtrusiveValidation.options.messages[elname][rulename]; //edit:use quoted strings for the name selector $("[name='" + elname + "']").rules("add", args); } }); } }); }; })(jQuery);

 public class HomeController : Controller { private const string sessionKey = "myFormKey"; public ActionResult Index() { Club club = null; if (Session[sessionKey] != null) { club = (Club) Session[sessionKey]; } else { club = new Club(); } return View(club); } //提交表单 [HttpPost] public ActionResult Index(Club club) { if (ModelState.IsValid) { StringBuilder sb = new StringBuilder(); sb.Append(club.Name); if (club.Players != null && club.Players.Count > 0) { foreach (var item in club.Players) { sb.AppendFormat("--{0}", item.Name); } } //删除Session //Session.Abandon(); //Session.Clear(); Session.Remove(sessionKey); return Content(sb.ToString()); } else { return View(club); } } //添加新行 public ActionResult NewPlayerRow(Player player) { return PartialView("_NewPlayer", player ?? new Player()); } //跳转之前把表单保存到Session中 [HttpPost] public ActionResult BeforeGoToMustSave(Club club) { Session[sessionKey] = club; return Json(new { msg = true }); } //保存完Club的Session后真正跳转到的页面 public ActionResult RealGoTo() { return View(); } }

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

@using MvcApplication1.Extension @model MvcApplication1.Models.Player 
 @using (Html.BeginCollectionItem("Players")) { @Html.HiddenFor(model => model.Id) 
 @Html.LabelFor(m => m.Name) @Html.TextBoxFor(m => m.Name) @Html.ValidationMessageFor(m => m.Name) 
 } 

using System; using System.Collections.Generic; using System.Web; using System.Web.Mvc; namespace MvcApplication1.Extension { public static class CollectionEditingHtmlExtensions { //目标生成如下格式 // //Title // // public static IDisposable BeginCollectionItem(this HtmlHelper html, string collectionName) { //构建name="FavouriteMovies.Index" string collectionIndexFieldName = string.Format("{0}.Index", collectionName); //构建Guid字符串 string itemIndex = GetCollectionItemIndex(collectionIndexFieldName); //构建带上集合属性+Guid字符串的前缀 string collectionItemName = string.Format("{0}[{1}]", collectionName, itemIndex); TagBuilder indexField = new TagBuilder("input"); indexField.MergeAttributes(new Dictionary() { {"name", string.Format("{0}.Index", collectionName)}, {"value", itemIndex}, {"type", "hidden"}, {"autocomplete", "off"} }); html.ViewContext.Writer.WriteLine(indexField.ToString(TagRenderMode.SelfClosing)); return new CollectionItemNamePrefixScope(html.ViewData.TemplateInfo, collectionItemName); } private class CollectionItemNamePrefixScope : IDisposable { private readonly TemplateInfo _templateInfo; private readonly string _previousPrfix; //通过构造函数，先把TemplateInfo以及TemplateInfo.HtmlFieldPrefix赋值给私有字段变量，并把集合属性名称赋值给TemplateInfo.HtmlFieldPrefix public CollectionItemNamePrefixScope(TemplateInfo templateInfo, string collectionItemName) { this._templateInfo = templateInfo; this._previousPrfix = templateInfo.HtmlFieldPrefix; templateInfo.HtmlFieldPrefix = collectionItemName; } public void Dispose() { _templateInfo.HtmlFieldPrefix = _previousPrfix; } } /// 
 /// /// 
 /// 比如，FavouriteMovies.Index /// Guid字符串 private static string GetCollectionItemIndex(string collectionIndexFieldName) { Queue previousIndices = (Queue)HttpContext.Current.Items[collectionIndexFieldName]; if (previousIndices == null) { HttpContext.Current.Items[collectionIndexFieldName] = previousIndices = new Queue(); string previousIndicesValues = HttpContext.Current.Request[collectionIndexFieldName]; if (!string.IsNullOrWhiteSpace(previousIndicesValues)) { foreach (string index in previousIndicesValues.Split(',')) { previousIndices.Enqueue(index); } } } return previousIndices.Count > 0 ? previousIndices.Dequeue() : Guid.NewGuid().ToString(); } } }

@{ ViewBag.Title = "RealGoTo"; Layout = "~/Views/Shared/_Layout.cshtml"; } 
RealGoTo
 @Html.ActionLink("回到表单页","Index","Home")