ASP.NET MVC与EntityFramework入门（一）
Razor视图
视图的相关约定
1.所有的视图必须放到Views目录下
Views\Home\index.cshtml
2.不同控制器的视图用文件夹进行分割，每个控制器都对应一个视图目录
HomeController.cs--Views\Home\...
MapController.cs--Views\Map\...
3.一般视图名字跟控制器的Action相对应（非必须）
4.多个控制器公共的视图放到Shared
public class HomeController : Controller
{
public ActionResult Index() // 视图 Views\Home\Index.cshtml
{
return View();
}
public ActionResult Get() // 视图 Views\Home\Get.cshtml
{
return View();
}
}
Razor引擎
@字符是Razor中一个重要的符号，它被定义为Razor服务器代码块的开始符号
Razor用法
1.输出单一变量
视图 Views\Home\Index.cshtml 中
--输出当前时间
<div>
@DateTime.Now
</div>
2.输出三元运算符
<div>
@{ var i = 3;
int[] nums = {1,4,6,7,3,8};
}
@(i == 3 ? "ok" : "no")
@if(i == 4)
{
@:启动
}
else
{
@:停止
}
@foreach(var item in nums)
{
@item
}
</div>
3.执行多行C#代码
4.Razor中注释
5.IF判断表达式
6.在程序区块中插入文字内容
7.foreach循环
MVC传值
传值方式：
1.Viewdata
2.Viewbag
3.TempData
4.Model(强类型传值)
--新建ASP.NET MVC 4 Web应用程序（MVC传值）--基本 --Controllers文件夹添加HomeController.cs
--添加Index方法对应的视图
public ActionResult Index()
{
Session["key"] = "hello";
String s = Session["key"]; //取值
ViewData["key"] = "hello";
ViewData["key"] //取值
ViewBag.key = "hi";
TempData["key"] = "hi";
return View();
}
<body>
<div>
@ViewData["key"]
@ViewBag.key
@TempData["key"]
</div>
</body>
Viewdata和Viewbag
添加一个类 Student.cs
public class Student
{
public int Sid{get;set;}
public string Sname{get;set;}
public int Age{get; set;}
public string sex{ get;set;}
public string inte { get; set;}
}
public ActionResult Demo
{
Student stu = new Student();
stu.Sid = 5;
stu.Sname = "liming";
stu.Age = 18;
ViewData["stu"] = stu;
ViewBag.stu = stu;
return View();
}
<div>
@{
@ViewData["stu"] as MVC传值.Models.Student //类型转换
MVC传值.Models.Student viewdataStu = (MVC传值.Models.Student) @ViewData["stu"];
MVC传值.Models.Student viewbagStu = ViewBag.stu;
}
@viewbagStu.Sname
@viewdataStu.Sname
</div>
当传过来的数据是强类型数据的时候，viewdata需要作数据类型转换，viewbag不需要
传基本数据类型 viewdata与viewbag没有区别
viewdata和tempdata
public ActionResult Index()
{
ViewData["abc"] = "abc";
return RedirectToAction("getValue");//返回到一个方法
}
public ActionResult getValue() //添加一个视图
{
return View();
//return ViewData["abc"].ToString(); 报错
}
//在视图getValue中无法获得ViewData["abc"]的值
public ActionResult Index()
{
TempData["abc"] = "abc";
return RedirectToAction("getValue");//返回到一个方法
}
public ActionResult getValue() //添加一个视图
{
return View();
//return TempData["abc"].ToString();
}
//在视图getValue中可以获得TempData["abc"]的值
通过ViewData传值时不可以跨方法，TempData可以跨方法传值
强类型传值
public ActionResult ModelDemo() //添加一个视图，勾选创建强类型视图，模型类选择Student类
{
Student stu = new Student();
stu.Sid = 1;
stu.Sname = "huahua";
stu.Age = 20；
return View(stu); //通过强类型传值
}
//ModelDemo.cshtml中
@modelodel MVC传值.Models.Student //表示传过来的为Student类型的对象
@Model List<MVC传值.Models.Student> //表示传过来的为Student类型对象的集合
<div>
@Model.Sname
</div>
request传值
<div>
<form action = "/formDemo/getStudent" method="post"> //提交到formDemoController控制器的getStudent方法
<table>
<tr><td>学生姓名：</td><td><input type = "text" name = "Sname"/></td></tr>
<tr><td>学生性别：</td><td><input type = "radio" name = "sex" value = "男"/>  
<input type = "radio" name = "sex" value = "女"/></td> </tr>
<tr><td>兴趣：</td> <td><input type = "checkbox" name = "inte" value="乒乓球"/>乒乓球
<input type = "checkbox" name = "inte" value="羽毛球"/>羽毛球
<input type = "checkbox" name = "inte" value="网球"/>网球
<input type = "checkbox" name = "inte" value="游泳"/>游泳
</td></tr>
<tr><td><input type = "submit" value = "提交"/></td></tr>
</table>
</form>
</div>
public class formDemoController : Controller
{
public ActionResult Index() //创建视图
{
return View();
}
public ActionResult getStudent() //使用request获取表单的值
{
string Sname = Request["Sname"];
string sex = Request["sex"];
string inte = Request["inte"];
return "姓名：" + Sname +" 性别：" + sex + "兴趣：" + inte;
}
//通过参数获取表单提交过来的数据
public ActionResult getStudentDemo1(string Sname,string sex)
{
return "姓名：" + Sname +" 性别：" + sex + "兴趣：" + Request["inte"];
}
}
对象传值
<div>
<form action = "/formDemo/getStudentDemo2" method="post"> //提交到formDemoController控制器的getStudentDemo2方法
<table>
<tr><td>学生姓名：</td><td><input type = "text" name = "Sname"/></td></tr>
<tr><td>学生性别：</td><td><input type = "radio" name = "sex" value = "男"/>  
<input type = "radio" name = "sex" value = "女"/></td> </tr>
<tr><td>兴趣：</td> <td><input type = "checkbox" name = "inte" value="乒乓球"/>乒乓球
<input type = "checkbox" name = "inte" value="羽毛球"/>羽毛球
<input type = "checkbox" name = "inte" value="网球"/>网球
<input type = "checkbox" name = "inte" value="游泳"/>游泳
</td></tr>
<tr><td><input type = "submit" value = "提交"/></td></tr>
</table>
</form>
</div>
public class formDemoController : Controller
{
public ActionResult Index() //创建视图
{
return View();
}
public ActionResult getStudent() //使用request获取表单的值
{
string Sname = Request["Sname"];
string sex = Request["sex"];
string inte = Request["inte"];
return "姓名：" + Sname +" 性别：" + sex + "兴趣：" + inte;
}
//通过参数获取表单提交过来的数据
public ActionResult getStudentDemo1(string Sname,string sex)
{
return "姓名：" + Sname +" 性别：" + sex + "兴趣：" + Request["inte"];
}
//通过对象
public string getStudentDemo2(Student stu)
{
stu.inte = Request["inte"];
//要求：表单input标签name值均一一对应属性值，点击提交，自动拼接对象，并将各值赋值到对象的属性中
return "姓名：" + stu.Sname +" 性别：" + stu.sex + "兴趣：" + stu.inte;
//通过这种方式复选框传不全，所以仍需要用Request传值方式
}
}
formcollection传值
<div>
<form action = "/formDemo/getStudentDemo3" method="post"> //提交到formDemoController控制器的getStudentDemo3方法
<table>
<tr><td>学生姓名：</td><td><input type = "text" name = "Sname"/></td></tr>
<tr><td>学生性别：</td><td><input type = "radio" name = "sex" value = "男"/>  
<input type = "radio" name = "sex" value = "女"/></td> </tr>
<tr><td>兴趣：</td> <td><input type = "checkbox" name = "inte" value="乒乓球"/>乒乓球
<input type = "checkbox" name = "inte" value="羽毛球"/>羽毛球
<input type = "checkbox" name = "inte" value="网球"/>网球
<input type = "checkbox" name = "inte" value="游泳"/>游泳
</td></tr>
<tr><td><input type = "submit" value = "提交"/></td></tr>
</table>
</form>
</div>
public class formDemoController : Controller
{
public ActionResult Index() //创建视图
{
return View();
}
public ActionResult getStudent() //使用request获取表单的值
{
string Sname = Request["Sname"];
string sex = Request["sex"];
string inte = Request["inte"];
return "姓名：" + Sname +" 性别：" + sex + "兴趣：" + inte;
}
//通过参数获取表单提交过来的数据
public ActionResult getStudentDemo1(string Sname,string sex)
{
return "姓名：" + Sname +" 性别：" + sex + "兴趣：" + Request["inte"];
}
//通过对象
public string getStudentDemo2(Student stu)
{
stu.inte = Request["inte"];
//要求：表单input标签name值均一一对应属性值，点击提交，自动拼接对象，并将各值赋值到对象的属性中
return "姓名：" + stu.Sname +" 性别：" + stu.sex + "兴趣：" + stu.inte;
//通过这种方式复选框传不全，所以仍需要用Request传值方式
}
//通过formcollection传值
public string getStudentDemo3(FormCollection col)
{
return "姓名：" + col["Sname"] +" 性别：" + col["sex"] + "兴趣：" + col["inte"]; //可以直接获取到复选框的值
}
}
