Mvc中ViewBag、ViewData、TempData如何使用 - shexunyu

对于我初学者来说，Mvc有很多都是我所迷惑的，也是我了解后所痴迷的。废话不多说，来谈谈我今天对Mvc这几个常用的对象的理解吧，这里面只简明概要叙述

ViewBag 获取动态视图数据字典 作用：给视图传递数据，不需要转换类型，由系统动态解析，比ViewData执行性能要差

ViewData   获取或设置视图数据的字典         给视图传递数据，需要转换成相应的类型，编写没有ViewBag方便，可读性强

TempData     临时数据的字典   给控制器或视图传递数据，需要和ViewData一样进行类型转换，可以在多个控制器或页面传值，但是只能读取一次就为null了

后台代码

//
		// GET: /CommonStudy/

		public ActionResult Index()
		{
			var model = Sxy.BLL.CradInfo.GetList("", "");

			this.ViewBag.SecondModelList = model.ToList();
			//自定义数据
			this.ViewData["ThirdModel"] = model.FirstOrDefault();
			//缓存,在下一个控制器可以取到当前的数据，但是只能去一次就释放了
			this.TempData["IndexCache"] = model.ToList();

			//只能被取一次，不管是视图使用还是控制器使用，只要其中一个使用了，当前临时缓存就为null了
			this.TempData["Temp"] = "设置一个缓存";

			return View(model);
		}


		//
		// GET: /CommonStudy/Create

		public ActionResult Create()
		{
			//获取IndexCache
			var tempData = this.TempData["IndexCache"];
			//转换成实例象
			var model = tempData as List<Sxy.Model.CradInfo>;
			var tempData2 = this.TempData["IndexCache"];
			//在当前控制存储，给后面一个控制器使用
			this.TempData["CreateCache"] = tempData2;

			//由于前面视图有使用到了这个临时缓存，现在已取不到了
			var temp = this.TempData["Temp"];

			return View();
		}

  //
		// POST: /CommonStudy/Create

		[HttpPost]
		public ActionResult Create(Sxy.Model.CradInfo model)
		{
			try
			{
				// TODO: Add insert logic here
				var tempData2 = this.TempData["IndexCache"];
				var createCache = this.TempData["CreateCache"];
				if (ModelState.IsValid)
				{
					if (Sxy.BLL.CradInfo.Add(model) > 0)
					{

					}
				}


				return RedirectToAction("Index");
			}
			catch
			{
				return View();
			}
		}

前台代码

@model IEnumerable<Sxy.Model.CradInfo>

@{
	ViewBag.Title = "Index";
}

<h2>Index</h2>

<p>
	@Html.ActionLink("Create New", "Create")
	@*临时数据*@
	@this.TempData["Temp"]

</p>
<table>
	<tr>
		<th>
			@Html.DisplayNameFor(model => model.userId)
		</th>
		<th>
			@Html.DisplayNameFor(model => model.carNumber)
		</th>
		<th>
			@Html.DisplayNameFor(model => model.carQueryPassword)
		</th>
		<th>
			@Html.DisplayNameFor(model => model.createTime)
		</th>
		<th></th>
	</tr>
	@*默认返回的Model*@
	@foreach (var item in Model)
	{
		<tr>
			<td>
				@Html.DisplayFor(modelItem => item.userId)
			</td>
			<td>
				@Html.DisplayFor(modelItem => item.carNumber)
			</td>
			<td>
				@Html.DisplayFor(modelItem => item.carQueryPassword)
			</td>
			<td>
				@Html.DisplayFor(modelItem => item.createTime)
			</td>
			<td>
			@Html.ActionLink("Edit", "Edit", new { id = item.id }) |
			@Html.ActionLink("Details", "Details", new { id = item.id }) |
			@Html.ActionLink("Delete", "Delete", new { id = item.id })
			</td>
		</tr>
	}

	<tr>
		<td colspan="5">
			<hr />
		</td>

	</tr>
	@*自定义ViewData*@
	@foreach (var item in ViewData["SecondModelList"] as List<Sxy.Model.CradInfo>)
	{
		<tr>
			<td>
				@Html.DisplayFor(modelItem => item.userId)
			</td>
			<td>
				@Html.DisplayFor(modelItem => item.carNumber)
			</td>
			<td>
				@Html.DisplayFor(modelItem => item.carQueryPassword)
			</td>
			<td>
				@Html.DisplayFor(modelItem => item.createTime)
			</td>
			<td>
				@Html.ActionLink("Edit", "Edit", new { id = item.id }) |
			@Html.ActionLink("Details", "Details", new { id = item.id }) |
			@Html.ActionLink("Delete", "Delete", new { id = item.id })
			</td>
		</tr>
	}

	<tr>
		<td style="width: auto">
			<hr />
		</td>

	</tr>


	@{ var ThirdModel = ViewData["ThirdModel"] as Sxy.Model.CradInfo;
		<tr>

			<td>
				@Html.DisplayFor(modelItem => ThirdModel.userId)
			</td>
			<td>
				@Html.DisplayFor(modelItem => ThirdModel.carNumber)
			</td>
			<td>
				@Html.DisplayFor(modelItem => ThirdModel.carQueryPassword)
			</td>
			<td>
				@Html.DisplayFor(modelItem => ThirdModel.createTime)
			</td>
			<td>
				@Html.ActionLink("Edit", "Edit", new { id = ThirdModel.id }) |
			@Html.ActionLink("Details", "Details", new { id = ThirdModel.id }) |
			@Html.ActionLink("Delete", "Delete", new { id = ThirdModel.id })
			</td>
		</tr>
		
	}



</table>