<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Index.aspx.cs" Inherits="WebApplication1.Index" %> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title></title>
</head>
<body>
<form id="form1" runat="server">
<div> <asp:Button ID="Button1" runat="server" Text="隐式类型局部变量" onclick="Button1_Click" /> <br />
<asp:Button ID="Button2" runat="server" onclick="Button2_Click" Text="自动属性" /> <br />
<asp:Button ID="Button3" runat="server" Text="对象初始化器" onclick="Button3_Click" /> <br />
<asp:Button ID="Button4" runat="server" Text="集合初始化器" onclick="Button4_Click" /> <br />
<asp:Button ID="Button5" runat="server" Text="匿名类型" onclick="Button5_Click" /> <br />
<asp:Button ID="Button6" runat="server" Text="扩展方法" onclick="Button6_Click"
style="height: 21px" /> <asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
<br />
<asp:Button ID="Button7" runat="server" Text="Lambda表达式"
onclick="Button7_Click" /> </div>
</form>
</body>
</html>
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls; namespace WebApplication1
{
//委托类型
public delegate int DelDemo(int a,int b); public partial class Index : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{ } protected void Button1_Click(object sender, EventArgs e)
{
//隐式类别局部变量
//1.定义时必须给值
//2.定义时变量的类型会根据值自动识别,所以在重新赋值时给的值必须对应类型的值
//3.局部变量可以用它定义
var v = ;
var v2 = 12.5; //v = "abc";//错
int i;
i = ;
//var v3;//错
//v3 = 20;
}
//自动属性
protected void Button2_Click(object sender, EventArgs e)
{
Student stu = new Student();
stu.Sex = "男";
stu.StuName = "张三";
stu.StuId = ""; }
//对象初始化
protected void Button3_Click(object sender, EventArgs e)
{
//可以少写构造函数，
Student stu = new Student() { StuId="" };
Student stu1 = new Student() { StuName = "李四", StuId = "" };
Student stu2 = new Student() { Sex = "男" };
}
//集合初始化器
protected void Button4_Click(object sender, EventArgs e)
{
int[] arr = { , , , };
List<int> list = new List<int>() { , , , }; Response.Write("长度:"+list.Count);
//例定义一个list，默认存放三个学生
List<Student> list1 = new List<Student>() {
new Student(){ StuId="",StuName="李四",Sex="男"},
new Student(){ StuId="",StuName="张三",Sex="女"},
new Student(){ StuId="", StuName="王五",Sex="男"} }; }
//匿名类型
protected void Button5_Click(object sender, EventArgs e)
{
//直接创建分数对象
var g = new { Gid = "", Score = , StuId = "" };//编译器会为我们自动生成一个类,类中包函以上属性
Response.Write("分数:"+g.Score);
}
//扩展方法
protected void Button6_Click(object sender, EventArgs e)
{
string pwd = TextBox1.Text;
string str = pwd.MD5();
string str1 = pwd.SHA1();
Response.Write("MD5加密后"+str);
Response.Write("SHA1加密后" + str1);
this.Alert("你好");
}
public int Sum(int a, int b)
{
return a + b;
} protected void Button7_Click(object sender, EventArgs e)
{
//Lambda表达本质上就是一个委托对象
DelDemo dd = new DelDemo(Sum);//委托的标准写法
//2.C#2.0中的匿名方法的写法
DelDemo dd2 = delegate(int a, int b)
{
return a - b;
};
//3.C#3.0中退出的Lambda表达式的写法
DelDemo dd3 = (a, b) => a - b;//{int x=a-b}; //调用委托的方法
int i = dd3(,);
Response.Write(i); //需要用Lambda表达式的扩展方法
List<int> list=new List<int>(){ ,,,,,};
int s = list.Sum();
Response.Write("所有人的成绩:"+s);
//把及格人的总分算出来
//func<方法的参数类型,方法的返回值类型>
Func<int, bool> f = (a) => a > ;
//where 查询符合委托条件的数，以集合返回
//IEnumerable是所有数组与集合父接口
IEnumerable<int> ds = list.Where(f);
int d = ds.Sum();
Response.Write("结果:"+d); } }
}
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web; namespace WebApplication1
{ public class Student
{
string stuId; public string StuId
{
get { return stuId; }
set { stuId = value; }
} string stuName; public string StuName
{
get { return stuName; }
set { stuName = value; }
}
//1.自动属性，在编译器编译时，会为这个属性生成一个变量
//get与set操作的是这个变量
//2.get与set必须都有 public string Sex{ get;set; } }
}