16

我正在尝试HTTP request使用套接字。我的代码如下：

using System;
using System.Net;
using System.Net.Sockets;
using System.Text;
class test
{
    public static void Main(String[] args)
    {
        string hostName = "127.0.0.1";
        int hostPort = 9887;
        int response = 0;

        IPAddress host = IPAddress.Parse(hostName);
        IPEndPoint hostep = new IPEndPoint(host, hostPort);
        Socket sock = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);

        sock.Connect(hostep);

        string request_url = "http://127.0.0.1/register?id=application/vnd-fullphat.test&title=My%20Test%20App";
        response = sock.Send(Encoding.UTF8.GetBytes(request_url));
        response = sock.Send(Encoding.UTF8.GetBytes("\r\n"));

        bytes = sock.Receive(bytesReceived, bytesReceived.Length, 0);
        page = page + Encoding.ASCII.GetString(bytesReceived, 0, bytes);
        Console.WriteLine(page);
        sock.Close();
    }
}

现在，当我执行上述代码时，什么也没有发生，而当我request_url在浏览器中输入时，我收到了来自 Snarl 的通知，说Application Registered我从浏览器得到的响应是

SNP/2.0/0/OK/556

我从我的代码中得到的响应是SNP/3.0/107/BadPacket.

那么，我的代码有什么问题。

Snarl 请求格式规范

4

4 回答 4

16

我对SNP一无所知。您的代码在接收部分有点混乱。我使用下面的示例来发送和读取 HTTP GET 请求的服务器响应。首先让我们看一下请求，然后检查响应。

HTTP GET 请求：

GET / HTTP/1.1
Host: 127.0.0.1
Connection: keep-alive
Accept: text/html
User-Agent: CSharpTests

string - "GET / HTTP/1.1\r\nHost: 127.0.0.1\r\nConnection: keep-alive\r\nAccept: text/html\r\nUser-Agent: CSharpTests\r\n\r\n"

服务器 HTTP 响应标头：

HTTP/1.1 200 OK
Date: Sun, 07 Jul 2013 17:13:10 GMT
Server: Apache/2.4.4 (Win32) OpenSSL/0.9.8y PHP/5.4.16
Last-Modified: Sat, 30 Mar 2013 11:28:59 GMT
ETag: \"ca-4d922b19fd4c0\"
Accept-Ranges: bytes
Content-Length: 202
Keep-Alive: timeout=5, max=100
Connection: Keep-Alive
Content-Type: text/html

string - "HTTP/1.1 200 OK\r\nDate: Sun, 07 Jul 2013 17:13:10 GMT\r\nServer: Apache/2.4.4 (Win32) OpenSSL/0.9.8y PHP/5.4.16\r\nLast-Modified: Sat, 30 Mar 2013 11:28:59 GMT\r\nETag: \"ca-4d922b19fd4c0\"\r\nAccept-Ranges: bytes\r\nContent-Length: 202\r\nKeep-Alive: timeout=5, max=100\r\nConnection: Keep-Alive\r\nContent-Type: text/html\r\n\r\n"

我故意省略了服务器响应的主体，因为我们已经知道它正好是 202 字节，由响应标头中的 Content-Length 指定。

查看 HTTP 规范会发现 HTTP 标头以空的新行（“\r\n\r\n”）结尾。所以我们只需要搜索它。

让我们看看一些实际的代码。假设 System.Net.Sockets.Socket 类型的变量套接字。

socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
socket.Connect("127.0.0.1", 80);
string GETrequest = "GET / HTTP/1.1\r\nHost: 127.0.0.1\r\nConnection: keep-alive\r\nAccept: text/html\r\nUser-Agent: CSharpTests\r\n\r\n";
socket.Send(Encoding.ASCII.GetBytes(GETrequest));

我们已经将请求发送到服务器，让我们接收并正确解析响应。

bool flag = true; // just so we know we are still reading
string headerString = ""; // to store header information
int contentLength = 0; // the body length
byte[] bodyBuff = new byte[0]; // to later hold the body content
while (flag)
{
// read the header byte by byte, until \r\n\r\n
byte[] buffer = new byte[1];
socket.Receive(buffer, 0, 1, 0);
headerString += Encoding.ASCII.GetString(buffer);
if (headerString.Contains("\r\n\r\n"))
{
    // header is received, parsing content length
    // I use regular expressions, but any other method you can think of is ok
    Regex reg = new Regex("\\\r\nContent-Length: (.*?)\\\r\n");
    Match m = reg.Match(headerString);
    contentLength = int.Parse(m.Groups[1].ToString());
    flag = false;
    // read the body
    bodyBuff = new byte[contentLength];
    socket.Receive(bodyBuff, 0, contentLength, 0);
}
}
Console.WriteLine("Server Response :");
string body = Encoding.ASCII.GetString(bodyBuff);
Console.WriteLine(body);
socket.Close();

这可能是在 C# 中执行此操作的最糟糕的方法，在 .NET 中有大量类可以处理 HTTP 请求和响应，但如果您需要它，它仍然可以工作。

于 2013-07-07T17:44:17.307 回答
12

您必须在末尾包含内容长度和双新行以指示标题的结尾。

var request = "GET /register?id=application/vnd-fullphat.test&title=My%20Test%20App HTTP/1.1\r\n" + 
    "Host: 127.0.0.1\r\n" +
    "Content-Length: 0\r\n" +
    "\r\n";

HTTP 1.1 规范可以在这里找到： http: //www.w3.org/Protocols/rfc2616/rfc2616.html

于 2012-08-08T11:22:36.167 回答
1

您的要求不正确。根据wikipedia，HTTP Get 请求必须如下所示：

string request = "GET /register?id=application/vnd-fullphat.test&title=My%20Test%20App HTTP/1.1\r\nHost: 127.0.0.1\r\n";
于 2012-08-08T10:58:09.360 回答
1

HTTP 请求的最低要求是“GET / HTTP/1.0\r\n\r\n”（如果允许删除主机）。但是在 SNARL 中，您必须输入内容长度（我听到最多的内容）。

所以，

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

        sck.Connect(ip, port);
        sck.Send(Encoding.UTF8.GetBytes("THE HTTP REQUEST HEADER"));
        Console.WriteLine("SENT");
        string message = null;
        byte[] bytesStored = new byte[sck.ReceiveBufferSize];
        int k1 = sck.Receive(bytesStored);
        for (int i = 0; i < k1; i++)
        {
            message = message + Convert.ToChar(bytesStored[i]).ToString();
        }
        Console.WriteLine(message); // PRINT THE RESPONSE

我在几个站点上进行了测试，并且效果很好。如果它不起作用，那么您应该通过添加更多标题来修复它（最有可能的解决方案）。

于 2016-09-24T09:51:40.930 回答