前台向后传值：
1.用网站网址自带参数向后传【http://localhost:5809/ProductInfo/CatogryProducts?categoryID=0021】，后台controller用string ID = Request.QueryString["categoryID"]接收，其中categoryID是参数名称。

2.ajax传值，其中$.post(url,data,success(data, textStatus, jqXHR),dataType)

参数     描述
url     必需。规定把请求发送到哪个 URL。
data     可选。映射或字符串值。规定连同请求发送到服务器的数据。
success(data, textStatus, jqXHR)     可选。请求成功时执行的回调函数。
dataType     可选。规定预期的服务器响应的数据类型。默认执行智能判断（xml、json、script 或 html）。

该函数是简写的 Ajax 函数，等价于：

$.ajax({
  type: 'POST',
  url: url,
  data: data,
  success: success,
  dataType: dataType
});

$.get()也差不多。百度

3.表单传值，表单元素的name属性必须和后台model类型一样，直接用一个对象接收。在form的action属性中引用controller的方法就可以

4.viewdata传值

控制器向视图中传值ViewData详解

　　1.将一个字符串传值到视图中

在action中我们将字符串保存在ViewData（或ViewBag [asp.net 3或以上才可用]）中代码如下：

public ActionResult Index()
        {
            ViewData["str1"]= "这是一个字符串";

//也可以使用ViewBag来传递值

ViewBag.str2="这是另外一个字符串";

return View();
        }

在视图中我们可以用下面代码将字符串显示出来

<h1>@ViewData["str1"]</h1>

<h1>@ViewBag.str2</h1>

2.将一个字符串集合传递到视图中

public ActionResult Index()
        {
           List<string> str1= new List<string>();
            str1.Add("1111");
            str1.Add("2222");
            str1.Add("3333");
            ViewData["str"] = str1;

return View();
        }

在视图中我们通过下面语句将str1的值显示出来

@foreach (var a in ViewData["str"] as List<string>)
         {
           @a
         }

3.将一个datatable的值传递到视图中

public ActionResult Index()
            {

DataTable newtable = new DataTable("d");
            newtable.Columns.Add("商品编号", typeof(string));
            newtable.Columns.Add("客户编号", typeof(string));
            DataRow NewRow = newtable.NewRow();
            NewRow["商品编号"] = "132323213434";
            NewRow["客户编号"] = "344223443244";
            newtable.Rows.Add(NewRow);
            DataRow SNewRow = newtable.NewRow();
            SNewRow["商品编号"] = "343432445456";
            SNewRow["客户编号"] = "454523432453";
            newtable.Rows.Add(SNewRow);
            ViewData["dt"]= newtable;
            return View();
            }

在视图中我们通过下面语句将dt的值显示出来

注意：在顶部要先加上：@using System.Data;

<ul>
            @foreach(DataRow dr in (ViewData["dt"] as DataTable).Rows)
               {
                 <li>
                 @dr["商品编号"],@dr["客户编号"],
                 </li>
                }
              </ul>

然后是ViewBag:

public ActionResult UsingViewBag()
{ViewBag.Title = " Using ViewBag";ViewBag.ProjectName = "My Test Project";ViewBag.ProjectDescription = "This is Test Project to demo Viewdata and viewbag details";ViewBag.StartDate = new DateTime(2011, 1, 1);ViewBag.TotalPrice = 1000;ViewBag.TotalDays = 100;Dictionary<string, string> stackholder = new Dictionary<string, string>();stackholder.Add("Client", "Mr.  Client");stackholder.Add("Manager", "Mr. Joy");stackholder.Add("Team Leader", "Mr.Toy");stackholder.Add("Sr. developer", "Mr.dojoy");stackholder.Add("developer", "Mr. nodoy");ViewBag.stackholder = stackholder;List<string> modules = new List<string>();modules.Add("Admin module");modules.Add("ShoppingCart module");modules.Add("CMS module");ViewBag.modules = modules;return View();
}

对应View UsingViewBag 的cshtml的ViewBag:

<h1>@ViewBag.Title</h1><div><div><h2>Project Name : @ViewBag.ProjectName</h2></div><div>ProjectDescription :   <p>"@ViewBag.ProjectDescription.</p></div><div>Stack Holder :<br /><ul id="stakholder">@foreach ( var stakerholder in ViewBag.stackholder ){          <li>@stakerholder.Key &nbsp; : @stakerholder.Value</li>}</ul></div><div>Project Details:<br /><div>module List  :<ul id="modulelist">@foreach ( var module in ViewBag.modules ){          <li>@module</li>}</ul></div>Project StartDate : @ViewBag.StartDate.ToString("dd-MMM-yyyy") <br />Project TotalPrice: @ViewBag.TotalPrice  ₹  <br />Project TotaDays  : @ViewBag.TotalDays </div></div>

在controll用ViewBag传一个 List<ProductInfo> list的列表中：

public ActionResult Index()
        {
            List<ProductInfo> list = new List<ProductInfo>();
            list.Add(new ProductInfo
            {
                Department = "1111aa",
                Describe = "1111aa",
                Brand = "1111aa",
                CategoryID = "1111aa",
                ProductID = "1111aa",
                Color = "1111aa",
                Cost = "1111aa",
                Note = "1111aa",
                Owner = "1111aa",
                PriceTag = "1111aa",
                ProductName = "98uy",
                ShelfLife = "1111aa",
                Size = "1111aa",
                Style = "1111aa",
            });
            ViewBag.list = list;
            return View();
        }

在前台中：
@foreach(var item in ViewBag.list){
    @item.ProductName;
    @item.Department;
}