在dotnet下用c#编写下载器

System.Net.WebClient client=new WebClient();

byte[] page=client.DownloadData("http://www.google.com");

string content=System.Text.Encoding.UTF8.GetString(page);

在dotnet下经常使用此类方法

string hostName="www.nnn.net";

label1.Text="xxx";

int port=80;

IPHostEntry ipInfo=Dns.GetHostByName(hostName);

//取得IPAddress[]

IPAddress[] ipAddr=ipInfo.AddressList;

//得到ip

IPAddress ip=ipAddr[0];

IPEndPoint hostEP=new IPEndPoint(ip,port);

Socket socket=new Socket(AddressFamily.InterNetwork,SocketType.Stream,ProtocolType.Tcp);

socket.Connect(hostEP);

string sendStr="GET "+"/tryst/default.asp"+" HTTP/1.1\r\nHost: " + hostName + "\r\nConnection: Close\r\n\r\n";

//创建bytes字节数组以转换发送串

byte[] bytesSendStr=new byte[1024];