web窗体的内置对象

内置对象：
1、Response - 响应请求对象
Response.Redirect("Default2.aspx"); //重定向
Response.Write("<script>window.open('Default2.aspx');</script>"); ---可以书写任何东西，直接输出出去

2、Request - 接收请求对象
Request["键"] - 放在等号右边，用来取值
服务器控件是根据ID来作为键
表单元素是根据name值来作为键

QueryString - 页面地址拼接数据
如：Default2.aspx?aaa=呵呵&bbb=嘿嘿&ccc=hoho

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;public partial class Default2 : System.Web.UI.Page
{protected void Page_Load(object sender, EventArgs e){Response.Write(Request["aaa"]);}
}

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;public partial class Default1 : System.Web.UI.Page
{protected void Page_Load(object sender, EventArgs e){Button1.Click += Button1_Click;}void Button1_Click(object sender, EventArgs e){Response.Redirect("Default2.aspx?aaa="+TextBox1.Text);//Response.Write("呵呵");
        }
}

using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;public partial class Default2 : System.Web.UI.Page
{protected void Page_Load(object sender, EventArgs e){TextBox1.Text=Request["aaa"];}
}

1.后台Response.Redirect("Default2.aspx?key="+值);
2.Form表单会通过submit按钮自动提交数据，将数据提交给action设置的页面中去，method=“get”方式来提交

method 提交方式
action 目标页面

get提交方式

<%@ Page Language="C#" AutoEventWireup="true"  CodeFile="Default1.aspx.cs" Inherits="Default1" EnableViewStateMac="false" %><!DOCTYPE html><html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<meta http-equiv="Content-Type" content="text/html; charset=utf-8"/><title></title>
</head>
<body><form id="form1" method="get" action="Default2.aspx" runat="server"><asp:TextBox ID="User" runat="server"></asp:TextBox><br /><asp:TextBox ID="Pwd" runat="server"></asp:TextBox><br /><asp:Button ID="Button1" runat="server" Text="Button" /></form>
</body>
</html>

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;public partial class Default1 : System.Web.UI.Page
{protected void Page_Load(object sender, EventArgs e){}}

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default2.aspx.cs" Inherits="Default2" EnableViewStateMac="false" %><!DOCTYPE html><html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<meta http-equiv="Content-Type" content="text/html; charset=utf-8"/><title></title>
</head>
<body><form id="form1" runat="server"><asp:TextBox ID="TextBox1" runat="server"></asp:TextBox></form>
</body>
</html>

using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;public partial class Default2 : System.Web.UI.Page
{protected void Page_Load(object sender, EventArgs e){TextBox1.Text=Request["User"]+"+"+Request["Pwd"];}
}

post提交方式 - 直接数据提交方式
除了不在地址栏拼接数据，其它的没有任何区别
===================================================================
3、Session
就是一个临时保存数据的对象，保存在服务器
可以理解为容器，变量

可以存Object类型，一个连接为独立的一组，默认生命周期为20分钟，如果在这20分钟内重新进行数据提交或是页面刷新，都会重置这20分钟倒计时时间。

如果Session["键"]里面没有内容的时候，使用时会抛出异常，所以一定要在使用session的值之前判断此是否为空。

注意：Session不要过度使用，因为放的东西太大了，用户连接多了就会导致内存溢出，服务器崩溃；也不要不使用，会造成资源浪费，因为内存中的数据是最快速的；

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default3.aspx.cs" Inherits="Default3" %><!DOCTYPE html><html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server"><meta http-equiv="Content-Type" content="text/html; charset=utf-8" /><title></title>
</head>
<body><form id="form1" runat="server">用户名：<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox><br />密码：<asp:TextBox ID="TextBox2" runat="server" TextMode="Password"></asp:TextBox><br /><asp:Button ID="Button1" runat="server" Text="登录" /><asp:Label ID="Label1" runat="server" Text=""></asp:Label></form>
</html>

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;public partial class Default3 : System.Web.UI.Page
{protected void Page_Load(object sender, EventArgs e){Button1.Click += Button1_Click;}void Button1_Click(object sender, EventArgs e){if(TextBox1.Text.Trim()=="zhangsan"&&TextBox2.Text.Trim()=="123"){Session["username"] = TextBox1.Text;Response.Redirect("Default4.aspx");}else{Label1.Text = "用户名密码错误";}}
}

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default4.aspx.cs" Inherits="Default4" %><!DOCTYPE html><html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<meta http-equiv="Content-Type" content="text/html; charset=utf-8"/><title></title>
</head>
<body><form id="form1" runat="server">这是session的主页面<br /><asp:Label ID="Label1" runat="server" Text="Label"></asp:Label></form>
</body>
</html>

using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;public partial class Default4 : System.Web.UI.Page
{protected void Page_Load(object sender, EventArgs e){if (Session["username"] != null){Label1.Text = Session["username"] + ",欢迎登录！";}else{Response.Redirect("Default3.aspx");}}
}

4、cookie
临时保存数据的一个对象，保存在客户端
不要保存很重要的信息，因为会随时被用户删掉，有些程序会自动抓取用户电脑上的cookie信息，如果密码保存进去了，就会被抓取到

赋值：使用Response对象
1、Response.Cookies.Add(new HttpCookie("键", 值));

2、Response.Cookies["键"].Value = 值;

3、制作持久Cookie ：
Response.Cookies["键"].Expires = DateTime.Now.AddDays(7);//设置7天后过期

取值：使用Request对象
Request.Cookies["UserName"].Value

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default5.aspx.cs" Inherits="Default5" %><!DOCTYPE html><html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<meta http-equiv="Content-Type" content="text/html; charset=utf-8"/><title></title>
</head>
<body><form id="form1" runat="server">用户名：<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox><br />密码：<asp:TextBox ID="TextBox2" runat="server"></asp:TextBox><br /><asp:Button ID="Button1" runat="server" Text="登录" /><br /><asp:CheckBox ID="CheckBox1" runat="server"  Text="7天自动登录"/><asp:Label ID="Label1" runat="server" Text=""></asp:Label></form>
</body>
</html>

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;public partial class Default5 : System.Web.UI.Page
{protected void Page_Load(object sender, EventArgs e){Button1.Click += Button1_Click;}void Button1_Click(object sender, EventArgs e){if(TextBox1.Text=="zhangsan"&&TextBox2.Text=="123"){Response.Cookies["username"].Value = TextBox1.Text;Response.Redirect("Default6.aspx");if(CheckBox1.Checked){Response.Cookies["username"].Expires = DateTime.Now.AddDays(7);}}else{Label1.Text = "用户名密码错误！";}}
}

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default6.aspx.cs" Inherits="Default6" %><!DOCTYPE html><html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<meta http-equiv="Content-Type" content="text/html; charset=utf-8"/><title></title>
</head>
<body><form id="form1" runat="server">这是cookie的主页面<br /><asp:Label ID="Label1" runat="server" Text=""></asp:Label><br /><asp:Button ID="Button1" runat="server" Text="退出" /></form>
</body>
</html>

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;public partial class Default6 : System.Web.UI.Page
{protected void Page_Load(object sender, EventArgs e){Button1.Click += Button1_Click;if (Request.Cookies["username"].Value!=null){Label1.Text = Request.Cookies["username"].Value + ",欢迎登录";}else{Response.Redirect("Default5.aspx");}}void Button1_Click(object sender, EventArgs e){Response.Cookies["username"].Expires = DateTime.Now.AddDays(-2);Response.Redirect("Default5.aspx");}
}