今天，我们来谈谈控制器与视图之间的数据传递。
数据传递，指的是视图与控制器之间的交互，包括两个方向上的数据交互，一个是把控制器的数据传到视图中，在视图中如何显示数据，一个是把视图数据传递到控制器中，
如何在控制器中获取，处理这些数据。
ASP.NET MVC 中所有控制器都继承Controller类，而Controller又继承自ControllerBase，而ControllerBase下又包含ViewData以及TempData视图数据字典。
一，使用ViewData传递数据
ViewData 只在当前 Action 中有效，生命周期和 View 相同，属于弱类型数据。用法与C#中字典用法相似，以键值对的方式进行存储。
ViewData可以存储任何数据类型，如类，DataTable，DataSet，json等。
用法举例：
public ActionResult Index() { ViewData["mydata"] = "index"; return View(); }
前台代码：
<%@ Page Language="C#" Inherits="System.Web.Mvc.ViewPage<dynamic>" %> <!DOCTYPE html> <html> <head runat="server"> <meta name="viewport" content="width=device-width" /> <title>Index</title> </head> <body> <div> <%=ViewData["mydata"] %> </div> </body> </html>
二，使用TempData传递数据
TempData与ViewData类似，以键值对的方式进行存储，保存在Session之中,进行一次读取之后Session就会消失,变为null。看下面代码：
public ActionResult Index() { //AVON.DMS.DAL.Entities DMS = new AVON.DMS.DAL.Entities(); //AVON.DMS.Model.REP A = DMS.REP.SingleOrDefault<AVON.DMS.Model.REP>(t => t.NO == "00561874"); //AVON.DMS.BLL.Rep repBLL = new AVON.DMS.BLL.Rep(); //AVON.DMS.Model.REP A = repBLL.GetFromRep("00561874"); //ViewData["mydata"] = A.JOINDATE; ViewData["mydata"] = "index"; TempData["mytemp"] = "huihui"; return View(); }
前端代码：
<%@ Page Language="C#" Inherits="System.Web.Mvc.ViewPage<dynamic>" %> <!DOCTYPE html> <html> <head runat="server"> <meta name="viewport" content="width=device-width" /> <title>Index</title> </head> <body> <div> <%=ViewData["mydata"] %> <%--<%=TempData["mytemp"] %>--%> <a href="add">跳转到下一页</a> </div> </body> </html>
在浏览器输入地址，http://localhost:7449/dms/index，显示如下：
点击"跳转到下一页"，进入http://localhost:7449/dms/add，显示如下：
我们看看add这个Action的代码：
public ActionResult Add() { ViewData["mydata"] = TempData["mytemp"]; //Session.Remove("temp"); return View(); }
前端：
<%@ Page Language="C#" Inherits="System.Web.Mvc.ViewPage<dynamic>" %> <!DOCTYPE html> <html> <head runat="server"> <meta name="viewport" content="width=device-width" /> <title>Add</title> </head> <body> <div> add <%=ViewData["mydata"] %> <a href="index">跳转到上一页</a> </div> </body> </html>
可见，add获取到了TempData["mytemp"]的值。我们尝试刷新一下http://localhost:7449/dms/add，显示如下：
ViewData["mttemp"]的值已经变为null，所以，可以看出TempData的值一旦读取，就会失效。需重新赋值。
三，使用Model传递数据
ViewData与TempData都是弱类型数据，那么如果我们想传递强类型数据，应该怎样编写代码呢？代码如下：
public ActionResult Detail() { DRMModel.Dealer dealer = new DRMModel.Dealer(); dealer.RecruiterID = "1"; dealer.Recruiter = "2"; dealer.NationalID = "2"; dealer.dealer_name = "dsdsds"; dealer.sex = "1"; dealer.BirthYear = "1989"; dealer.BirthMonth = "09"; dealer.BirthDay = "01"; var Model = dealer; return View(Model); }
右击detail方法，添加视图，勾选 Create a strongly-typed view,如下图：
点击添加之后，编写如下代码：
<%@ Page Language="C#" Inherits="System.Web.Mvc.ViewPage<DRMModel.Dealer>" %> <!DOCTYPE html> <html> <head runat="server"> <meta name="viewport" content="width=device-width" /> <title>Detail</title> </head> <body> <div> <%=Model.dealer_name %> </div> </body> </html>
在浏览器输入地址：http://localhost:55706/home/detail，显示如下：
当然，你也可以编写更为复杂的类，传递多个数据对象进行数据绑定。如下图：
public ActionResult Bind() { DRMModel.NewDealer newDealer = new DRMModel.NewDealer(); DRMModel.Dealer dealer = new DRMModel.Dealer(); dealer.RecruiterID = "1"; dealer.Recruiter = "2"; dealer.NationalID = "2"; dealer.dealer_name = "dsdsds"; dealer.sex = "1"; dealer.BirthYear = "1989"; dealer.BirthMonth = "09"; dealer.BirthDay = "01"; DRMModel.Contact contact = new DRMModel.Contact(); DRMModel.HouseAddress ha = new DRMModel.HouseAddress(); DRMModel.RDaddress rd = new DRMModel.RDaddress(); DRMModel.SendAddress sa = new DRMModel.SendAddress(); newDealer.Contact = contact; newDealer.HouseAddress = ha; newDealer.RDaddress = rd; newDealer.SendAddress = sa; newDealer.Dealer = dealer; var Model = newDealer; return View(Model); }
以上都是谈了控制器往视图传递数据，那么，控制器怎么获取视图提交的数据呢？今天，我们只介绍获取Post方式传送数据的方法。
假设，表单通过Post方式提交了，下列数据：RecruiterID = "1";Recruiter = "2";NationalID = "2";dealer_name = "dsdsds";
看以下方法代码：
/// <summary> /// 处理表单提交数据，方法1:使用传统的Request请求取值 /// </summary> /// <returns></returns> [HttpPost] public ActionResult AcceptFrom() { ViewData["RecruiterID"] = Request.Form["RecruiterID"]; ViewData["Recruiter"] = Request.Form["Recruiter"]; ViewData["NationalID"] = Request.Form["NationalID"]; ViewData["dealer_name"] = Request.Form["dealer_name"]; return View(); } /// <summary> /// 处理表单提交数据，方法2:Action参数名与表单元素name值一一对应 /// </summary> /// <param name="RecruiterID"></param> /// <param name="Recruiter"></param> /// <param name="NationalID"></param> /// <param name="dealer_name"></param> /// <returns></returns> [HttpPost] public ActionResult AcceptbyPara(string RecruiterID, string Recruiter, string NationalID, string dealer_name) { ViewData["RecruiterID"] = RecruiterID; ViewData["Recruiter"] = Recruiter; ViewData["NationalID"] = NationalID; ViewData["dealer_name"] = dealer_name; return View(); } /// <summary> /// 处理表单提交数据，方法3:从MVC封装的FormCollection容器中读取 /// </summary> /// <param name="form"></param> /// <returns></returns> [HttpPost] public ActionResult AcceptCollection(FormCollection form) { ViewData["RecruiterID"] = form["RecruiterID"]; ViewData["Recruiter"] = form["Recruiter"]; ViewData["NationalID"] = form["NationalID"]; ViewData["dealer_name"] = form["dealer_name"]; return View(); } /// <summary> /// 处理表单提交数据，方法4:使用实体作为Action参数传入，前提是提交的表单元素名称与实体属性名称一一对应 /// </summary> /// <param name="dealer"></param> /// <returns></returns> [HttpPost] public ActionResult AcceptbyModel(DRMModel.Dealer dealer) { ViewData["RecruiterID"] = dealer.RecruiterID; ViewData["Recruiter"] = dealer.Recruiter; ViewData["NationalID"] = dealer.NationalID; ViewData["dealer_name"] = dealer.dealer_name; return View(); }
假如。我们要传json数据呢，又应该怎么处理呢？看以下的例子：
我在HomeController 下的Index方法添加如下代码，模拟Post提交json数据。
public ActionResult Index() { DRMModel.NewDealer newDealer = new DRMModel.NewDealer(); DRMModel.Dealer dealer = new DRMModel.Dealer(); dealer.RecruiterID = "1"; dealer.Recruiter = "2"; dealer.NationalID = "2"; dealer.dealer_name = "dsdsds"; dealer.sex = "1"; dealer.BirthYear = "1989"; dealer.BirthMonth = "09"; dealer.BirthDay = "01"; DRMModel.Contact contact = new DRMModel.Contact(); DRMModel.HouseAddress ha = new DRMModel.HouseAddress(); DRMModel.RDaddress rd = new DRMModel.RDaddress(); DRMModel.SendAddress sa = new DRMModel.SendAddress(); newDealer.Contact = contact; newDealer.HouseAddress = ha; newDealer.RDaddress = rd; newDealer.SendAddress = sa; newDealer.Dealer = dealer; JavaScriptSerializer json = new JavaScriptSerializer(); string postdata = json.Serialize(newDealer); //postdata = "RecruiterID=1&Recruiter=2&NationalID=1&dealer_name=fafaf&sex=1&BirthYear=1989&BirthMonth=09&BirthDay=01"; string pageHtml = ""; //var httpWebRequest = (HttpWebRequest)WebRequest.Create("http://avondms.avon.com.tw/DMS/DMSApi/api/Newdealer/add"); var httpWebRequest = (HttpWebRequest)WebRequest.Create("http://localhost:55706/home/add"); //httpWebRequest.ContentType = "text/json"; //httpWebRequest.ContentType = "application/x-www-form-urlencoded"; httpWebRequest.ContentType = "application/json"; httpWebRequest.Method = "POST"; using (var streamWriter = new StreamWriter(httpWebRequest.GetRequestStream())) { streamWriter.Write(postdata); streamWriter.Flush(); streamWriter.Close(); } var httpResponse = (HttpWebResponse)httpWebRequest.GetResponse(); using (var streamReader = new StreamReader(httpResponse.GetResponseStream())) { pageHtml = streamReader.ReadToEnd(); } ViewData["pram1"] = pageHtml; return View(); }
在HomeController add方法添加如下代码：
[HttpPost] public string add(DRMModel.NewDealer newDealer) { //string rtn = Request.Form["dealer_name"]; string rtn = newDealer.Dealer.dealer_name; return rtn; }
在浏览器中输入地址：http://localhost:55706/home/index,显示如下：
由此可见，ASP.NET MVC 可把json数据转化为C#中的强类型数据，只要数据一一对应。
好了，今天写到这里，希望对您有所帮助，O(∩_∩)O哈哈~