网络编程之WebClient,WebRequest和WebResponse类

            WebClient web = new WebClient();
            Stream stream = web.OpenRead("http://www.reuters.com");
            StreamReader sr = new StreamReader(stream);
            while (sr.ReadLine() != null)
            {
                string line;
                line = sr.ReadLine();
                listBox1.Items.Add(line);
            }
            stream.Close();

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Net;
using System.IO;
using System.Threading;

namespace WindowsFormsApplication1
{
    public delegate void mydelegate(WebHeaderCollection s); //声明委托
    public partial class Form1 : Form
    {
        Thread x;
        public Form1()
        {
            InitializeComponent();
            WebRequest wrq = WebRequest.Create("http://www.reuters.com");
            //定义一个线程
            x = new Thread(doresponse);
            //启动线程
            x.Start(wrq);
        }

        private void doresponse(object ar)
        {
            WebRequest wrq = (WebRequest)ar;
            WebResponse wrp = wrq.GetResponse();
            WebHeaderCollection whc = wrp.Headers;//wrp.Headers：获取与请求相关联的标头值的集合
            mydelegate my = new mydelegate(settext);//声明委托执行的方法为settext（）
            this.Invoke(my, new object[] { whc });//在拥用此控件的基础窗体句柄的线程上执行指定的委托,此方法第二参数用于传入方法,代替形参whc
        }
        
        private void settext(WebHeaderCollection whc)
        {
            for (int i = 0; i < whc.Count; i++)
            {
                listBox1.Items.Add(string.Format("name {0}：{1}", whc.GetKey(i), whc[i]));//GetKey(i)代表获取指定索引的标头名称，whc[i]和whc.Get(i)代表获取特定标头名称的值
                listBox1.Items.Add(string.Format("name name {0}：{1}", whc.GetKey(i), whc.Get(i)));
            }
            x.Abort();//关闭这个线程
        }

    }
}

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Net;
using System.IO;
using System.Threading;

namespace WindowsFormsApplication1
{
    public delegate void mydelegate(WebHeaderCollection s); 
    public partial class Form1 : Form
    {
        Thread x;
        public Form1()
        {
            InitializeComponent();
            WebRequest wrq = WebRequest.Create("http://www.reuters.com");
            //把身份验证证书附在请求中
            NetworkCredential myCredentials = new NetworkCredential("lzw", "123");
            HttpWebRequest hwrq = (HttpWebRequest)wrq;//可以在任何需要WebRequest类的地方使用派生类HttpWebRequest
            hwrq.Credentials = myCredentials;//获取身份验证信息
            //HttpWebRequest类特有的属性：
            listBox1.Items.Add("等待异常抛出的时间：" + hwrq.Timeout);//hwrq.Timeout默认值100000毫秒
            listBox1.Items.Add("是否与 Internet 资源建立持久性连接:" + hwrq.KeepAlive);//默认为true
            listBox1.Items.Add("是否自动跟随web重定向响应：" + hwrq.AllowAutoRedirect);//默认为true
            //异步页面请求
            IAsyncResult ar = hwrq.BeginGetResponse(null, null);
            hwrq = (HttpWebRequest)ar.AsyncState;
            WebResponse wrp = wrq.EndGetResponse(ar);
            WebHeaderCollection whc = wrp.Headers;//wrp.Headers：获取与请求相关联的标头值的集合
            for (int i = 0; i < whc.Count; i++)
            {
                listBox1.Items.Add(string.Format("name {0}：{1}", whc.GetKey(i), whc[i]));//GetKey(i)代表获取指定索引的标头名称，whc[i]和whc.Get(i)代表获取特定标头名称的值
                listBox1.Items.Add(string.Format("name name {0}：{1}", whc.GetKey(i), whc.Get(i)));
            }
        }
    }
}