C# VC HTTP POST GET
post 提交用户输入的方式是隐含提交，在ASP端用request.getform()来获取输入域的值；
get 提交用户输入的方式是显式提交，提交时在浏览器的地址栏里可以看见用户输入的内容(你在Google中输入Java搜索，你按查找后可以在地址栏里看到java)，在ASP端用request.getquery()来获取输入域的值；
SUMMARY
To properly simulate a Form submission using WinInet, you need to send a header that indicates the proper Content-Type. For Forms, the proper Content-Type header is: Content-Type: application/x-www-form-urlencoded
摘要：
为了通过WinInet模拟一个表单，你需要发送一个header，来指示 Content-Type的内容。一般就是：Content-Type: application/x-www-form-urlencoded
MORE INFORMATION
In many cases, the server does not respond appropriately if a Content-Type is not specified. For example, the Active Server Pages component of IIS 3.0 actually checks this header specifically for 'application/x-www-form- urlencoded' before adding form variables to the "Request.Form" object. This MIME/Content-Type indicates that the data of the request is a list of URL- encoded form variables. URL-encoding means that space character (ASCII 32) is encoded as '+', special character such '!' encoded in hexadecemal form as '%21'.
了解更多：
在许多情况下，如果Content-Type 未指定的话，服务器的返回可能就不对。比如说：IIS 3.0的ASP组件会在给"Request.Form" 对象加入变量前，检查header 是否是 'application/x-www-form- urlencoded' 。MIME/Content-Type 表明请求的数据是一个URL- encoded的数组变量。URL-encoding 意味着空格 (ASCII 32) 被 '+'替换，特殊字符都被用相应的十六进制形式替换了，比如 '!'->'%21'。
Here is a snippet of code that uses the MFC WinInet classes to simulate a Form POST request:
下面是一段用MFC 的WinInet 类来模拟表单提交的代码：
CString strHeaders =
_T("Content-Type: application/x-www-form-urlencoded");
// URL-encoded form variables -
// name = "John Doe", userid = "hithere", other = "P&Q"
CString strFormData = _T("name=John+Doe&userid=hithere&other=P%26Q");
CInternetSession session;
CHttpConnection* pConnection =
session.GetHttpConnection(_T("ServerNameHere"));
CHttpFile* pFile =
pConnection->OpenRequest(CHttpConnection::HTTP_VERB_POST,
_T("FormActionHere"));
BOOL result = pFile->SendRequest(strHeaders,
(LPVOID)(LPCTSTR)strFormData, strFormData.GetLength());
不用 MFC，用SDK实现以上的功能：
Without MFC, the same code translates to straight SDK calls as follows:
static TCHAR hdrs[] =
_T("Content-Type: application/x-www-form-urlencoded");
static TCHAR frmdata[] =
_T("name=John+Doe&userid=hithere&other=P%26Q");
statuc TCHAR accept[] =
_T("Accept: */*");
// for clarity, error-checking has been removed
HINTERNET hSession = InternetOpen("MyAgent",
INTERNET_OPEN_TYPE_PRECONFIG, NULL, NULL, 0);
HINTERNET hConnect = InternetConnect(hSession, _T("ServerNameHere"),
INTERNET_DEFAULT_HTTP_PORT, NULL, NULL, INTERNET_SERVICE_HTTP, 0, 1);
HINTERNET hRequest = HttpOpenRequest(hConnect, "POST",
_T("FormActionHere"), NULL, NULL, accept, 0, 1);
HttpSendRequest(hRequest, hdrs, strlen(hdrs), frmdata, strlen(frmdata));
// close any valid internet-handles
用C#实现：
//把sXmlMessage发送到指定的DsmpUrl地址上
Encoding encode = System.Text.Encoding.GetEncoding("utf-8");
byte[] arrB = encode.GetBytes(sXmlMessage);
HttpWebRequest myReq = (HttpWebRequest)WebRequest.Create(DsmpUrl);
myReq.Method = "POST" ;
myReq.ContentType = "application/x-www-form-urlencoded";
myReq.ContentLength = arrB.Length;
Stream outStream = myReq.GetRequestStream();
outStream.Write(arrB,0,arrB.Length);
outStream.Close();
//接收HTTP做出的响应
WebResponse myResp = myReq.GetResponse();
Stream ReceiveStream = myResp.GetResponseStream();
StreamReader readStream = new StreamReader( ReceiveStream, encode );
Char[] read = new Char[256];
int count = readStream.Read( read, 0, 256 );
string str = null;
while (count > 0)
{
str += new String(read, 0, count);
count = readStream.Read(read, 0, 256);
}
readStream.Close();
myResp.Close();
public static string PostData( string str)
{
try
{
byte[] data = System.Text.Encoding.GetEncoding ("GB2312").GetBytes ( str ) ;
// 准备请求...
HttpWebRequest req = (HttpWebRequest) WebRequest.Create ( LMMPUrl ) ;
req.Method = "Post" ;
req.ContentType ="application/x-www-form-urlencoded";
req.ContentLength = data.Length ;
Stream stream = req.GetRequestStream () ;
// 发送数据
stream.Write ( data ,0 ,data.Length ) ;
stream.Close () ;
HttpWebResponse rep = (HttpWebResponse)req.GetResponse();
Stream receiveStream = rep.GetResponseStream();
Encoding encode = System.Text.Encoding.GetEncoding("GB2312");
// Pipes the stream to a higher level stream reader with the required encoding format.
StreamReader readStream = new StreamReader( receiveStream, encode );
Char[] read = new Char[256];
int count = readStream.Read( read, 0, 256 );
StringBuilder sb = new StringBuilder ("") ;
while (count > 0)
{
String readstr = new String(read, 0, count);
sb.Append ( readstr ) ;
count = readStream.Read(read, 0, 256);
}
rep.Close();
readStream.Close();
return sb.ToString () ;
}
catch(Exception ex)
{
return "" ;
ForumExceptions.Log ( ex ) ;
}
}