利用HttpRequest登录到某个网站,然后获取网站信息的程序示例

利用HttpRequest登录到某个网站,然后获取网站信息的程序示例 问: 有的网站的相关必须要在登录后才可以查看，其登录信息保存在session变量之中。 这样，使用asphttp等组件就难以正确得到所要的信息。 解决: 使用asp.net中的httprequest和httpresponse来实现。 要点: 1。 通过附加一个cookiecontainer到httprequest对象中，可以得到登录后返回的代 SESSION ID的COOKIE。 见Login 2。 将此COOKIE包含在一个cookiecontainer中并附加到另一个HTTPREQUEST请求中， 则可以实现SESSION的还原。见getPage方法 源程序如下: getHttpInfo.aspx: 复制ASPX代码保存代码<%@ Page Language="c#" Codebehind="getHttpInfo.aspx.cs" AutoEventWireup="false" Inherits="PdfTest.getHttpInfo" %>

<%@ Page Language="c#" Codebehind="getHttpInfo.aspx.cs" AutoEventWireup="false" Inherits="PdfTest.getHttpInfo" %>

getHttpInfo.aspx.cs: 复制C#代码保存代码using System; using System.Collections; using System.ComponentModel; using System.Data; //using System.Data.OleDb; using System.Drawing; using System.Web; using System.Web.SessionState; using System.Web.UI; using System.Web.UI.WebControls; using System.Web.UI.HtmlControls; using System.Net; using System.IO; using System.Text; using System.Text.RegularExpressions; using Microsoft.Data.Odbc; namespace PdfTest { ///

/// Summary description for WebForm1. ///

public class getHttpInfo : System.Web.UI.Page { protected static string cookieheader; private void Page_Load(object sender, System.EventArgs e) { // Put user code to initialize the page here string strResult; if (HttpContext.Current.Application["cookieheader"] != null) { cookieheader = (string) HttpContext.Current.Application["cookieheader"]; } else { //Login into the website and keep the cookie for the session in the application variable string strLogin = Login(";, "Action=&USERID=&Password="); } strResult = getPage(";, "Action=&data="); //Write the result to htm file FileStream htmFile = new FileStream(@"c:\save.htm", FileMode.OpenOrCreate); StreamWriter sw = new StreamWriter(htmFile); sw.Write(strResult); sw.Close(); htmFile.Close(); // output the result Response.Write(strResult); } public static string Login(String url, String paramList) { HttpWebResponse res = null; string strResult = ""; try { HttpWebRequest req = (HttpWebRequest) WebRequest.Create(url); req.Method = "POST"; req.ContentType = "application/x-www-form-urlencoded"; req.AllowAutoRedirect = false; CookieContainer cookieCon = new CookieContainer(); req.CookieContainer = cookieCon; StringBuilder UrlEncoded = new StringBuilder(); Char[] reserved = { '?', '=', '&' }; byte[] SomeBytes = null; if (paramList != null) { int i = 0, j; while (i < paramList.Length) { j = paramList.IndexOfAny(reserved, i); if (j == -1) { UrlEncoded.Append(HttpUtility.UrlEncode(paramList.Substring(i, paramList.Length - i))); 转载请附带本文地址: