第一种：<a href="/User/Index">链接到User/Index</a><br />//当路由规则(App_Start文件夹下的RouteConfig)发生变化时(比如/变成-)这种方法就失效了第二种：<a href="<%:Url.Action("Index","User") %>">链接</a><br />跳转到User控制器下的Index方法第三种：<%:Html.ActionLink("链接不带参","Index","User",new {name="itcast"}) %><br /><%:Html.ActionLink("链接不带参","Index","User") %><br/>

  public ActionResult HtmlHelper(){ViewBag.city = new List<SelectListItem>(){new SelectListItem(){Selected =true,Text = "北京",Value = "1"},new SelectListItem(){Selected =false,Text = "上海",Value = "2"},new SelectListItem(){Selected =false,Text = "广州",Value = "3"}};ViewBag.demo = "你好";return View();}

<div><%:Html.DropDownList("city") %> //HTML铺助方法会自动帮你把名字相同的进行匹配，比如city和ViewBag.City       //ViewBage.name是ViewData["name"]的一个动态封装器<%:Html.TextBox("demo") %><br />男<%:Html.RadioButton("gender","1",false) %>女<%:Html.RadioButton("gender","0",true) %></div>

public static class myhtmlhelper{public static string myLabel(this HtmlHelper helper, string txt){//要被编码化<span>属于html标签被编码了，就不死html标签是一个txt了return string.Format("<span>{0}</span>",txt);}public static HtmlString myhtmlstringLabel(this HtmlHelper helper, string txt){//不被编码化return new HtmlString(string.Format("<span>{0}</span>", txt));}}

<%:Html.myhtmlstringLabel("我的扩展方法") %>//调用的时候会发现需要引用System.Web.Mvc

namespace System.Web.Mvc/*命名空间改成引用的命名空间，前台页面就无需引用了*/
{/// <summary>/// 扩展htmlhelper方法/// </summary>public static class myhtmlhelper{public static string myLabel(this HtmlHelper helper, string txt){//要被编码化return string.Format("<span>{0}</span>",txt);}public static HtmlString myhtmlstringLabel(this HtmlHelper helper, string txt){//不被编码化return new HtmlString(string.Format("<span>{0}</span>", txt));}}
}