本文实例总结了三种常用的C#网页信息采集方法。分享给大家供大家参考。具体实现方法如下：

一、通过HttpWebResponse 来获取

复制代码 代码如下:public static string CheckTeamSiteUrl(string url)
{
string response = "";
HttpWebResponse httpResponse = null;

//assert: user have access to URL
try
{
HttpWebRequest httpRequest = (HttpWebRequest)WebRequest.Create(url);
httpRequest.Headers.Set("Pragma", "no-cache");

// request.Headers.Set("KeepAlive", "true");

httpRequest.CookieContainer = new CookieContainer();



httpRequest.Referer = url;

httpRequest.UserAgent = "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.0; .NET CLR 1.1.4322; .NET CLR 2.0.50727)";



httpRequest.Credentials = System.Net.CredentialCache.DefaultCredentials;
httpResponse = (HttpWebResponse)httpRequest.GetResponse();

}
catch (Exception ex)
{
throw new ApplicationException("HTTP 403 Access denied, URL: " + url, ex);
}

//if here, the URL is correct and the user has access
try
{
string strEncod = httpResponse.ContentType;
StreamReader stream;
if (strEncod.ToLower().IndexOf("utf") != -1)
{
stream = new StreamReader(httpResponse.GetResponseStream(), System.Text.Encoding.UTF8);
}
else
{
stream = new StreamReader(httpResponse.GetResponseStream(), System.Text.Encoding.Default);
}

char[] buff = new char[4000];
stream.ReadBlock(buff,0,4000);
response = new string(buff);
stream.Close();
httpResponse.Close();
}
catch (Exception ex)
{
throw new ApplicationException("HTTP 404 Page not found, URL: " + url, ex);
}
return response;
}

二、通过 WebResponse 来获取

复制代码 代码如下:public static string getPage(String url)
{
WebResponse result = null;
string resultstring = "";
try
{
WebRequest req = WebRequest.Create(url);
req.Timeout = 30000;
result = req.GetResponse();
Stream ReceiveStream = result.GetResponseStream();

//read the stream into a string
//StreamReader sr = new StreamReader(ReceiveStream, System.Text.Encoding.UTF8);
string strEncod = result.ContentType;
StreamReader sr;
if (strEncod.ToLower().IndexOf("utf") != -1)
{
sr = new StreamReader(ReceiveStream, System.Text.Encoding.UTF8);
}
else
{
sr = new StreamReader(ReceiveStream, System.Text.Encoding.Default);
}
resultstring = sr.ReadToEnd();
js.alert(resultstring);
//Console.WriteLine(resultstring);
}
catch
{
throw new Exception();
}
finally
{
if (result != null)
{
result.Close();
}
}
return resultstring;
}

三、通过WebClient来获取

复制代码 代码如下:public string get(int length)
{
try
{
getEncodeing();
WebClient wb = new WebClient();
Stream response = wb.OpenRead(url);
StreamReader reader = new StreamReader(response, this.encoding, true, 256000);
char[] a = new char[length];
int i = reader.Read(a,0,length);
reader.Close();
return new string(a);
}
catch (Exception e)
{
return e.Message;
//return null;
}
}
private void getEncodeing()
{
switch (this.encode)
{
case "UTF-8": encoding = Encoding.UTF8; break;
case "GB2312": encoding = Encoding.GetEncoding("GB2312"); break;
case "ASCII": encoding = Encoding.ASCII; break;
default: encoding = Encoding.GetEncoding(encode); break;
}
}

希望本文所述对大家的C#程序设计有所帮助。