.
Using POST with HTTP 1.1 implies the use of a "Expect: 100-continue" header. You can disable this header with CURLOPT_HTTPHEADER as usual.
When setting CURLOPT_HTTPPOST, it will automatically set CURLOPT_NOBODY to 0 (since 7.14.1).
CURLOPT_POST --application/x-www-form-urlencoded形式
A non-zero parameter tells the library to do a regular HTTP post. This will also make the library use the a "Content-Type: application/x-www-form-urlencoded" header. (This is by far the most commonly used POST method).
Use one of CURLOPT_POSTFIELDS or CURLOPT_COPYPOSTFIELDS options to specify what data to post and CURLOPT_POSTFIELDSIZE or CURLOPT_POSTFIELDSIZE_LARGE to set the data size.
Optionally, you can provide data to POST using the CURLOPT_READFUNCTION and CURLOPT_READDATA options but then you must make sure to not set CURLOPT_POSTFIELDS to anything but NULL. When providing data with a callback, you must transmit it using chunked transfer-encoding or you must set the size of the data with the CURLOPT_POSTFIELDSIZE or CURLOPT_POSTFIELDSIZE_LARGE option. To enable chunked encoding, you simply pass in the appropriate Transfer-Encoding header, see the post-callback.c example.
You can override the default POST Content-Type: header by setting your own with CURLOPT_HTTPHEADER.
Using POST with HTTP 1.1 implies the use of a "Expect: 100-continue" header. You can disable this header with CURLOPT_HTTPHEADER as usual.
If you use POST to a HTTP 1.1 server, you can send data without knowing the size before starting the POST if you use chunked encoding. You enable this by adding a header like "Transfer-Encoding: chunked" with CURLOPT_HTTPHEADER. With HTTP 1.0 or without chunked transfer, you must specify the size in the request.
When setting CURLOPT_POST to a non-zero value, it will automatically set CURLOPT_NOBODY to 0 (since 7.14.1).
If you issue a POST request and then want to make a HEAD or GET using the same re-used handle, you must explicitly set the new request type using CURLOPT_NOBODY or CURLOPT_HTTPGET or similar.
以上是两种POST方式，具体代码如下:
ALLUPLOADFILES::iterator iter = allFiles.begin();
//如果含有文件 //name="files"; filename="file1.txt"
if( bFileFlag ) //以form-dataf方式post
{
for (;iter != allFiles.end();iter++)
{
if ( iter->isFile )
{
my_bytestr_url_encode(iter->fileName);
curl_formadd(&post, &last, CURLFORM_COPYNAME , iter->contrlID.c_str(),
CURLFORM_BUFFER, iter->fileName.c_str(),
CURLFORM_BUFFERPTR,iter->data.c_str(),
CURLFORM_END);
}
else
{
curl_formadd(&post, &last, CURLFORM_COPYNAME , iter->contrlID.c_str(),
CURLFORM_COPYCONTENTS,iter->data.c_str(),
CURLFORM_END);
}
}
}
else //以application/x-www-form-urlencoded方式post
{
for (;iter != allFiles.end();iter++)
{
my_bytestr_url_encode(iter->contrlID);
my_bytestr_url_encode(iter->data);
postbuffer += iter->contrlID;
postbuffer += "=";
postbuffer += iter->data;
postbuffer += "&";
}
}
if (bFileFlag)
curl_easy_setopt(curl, CURLOPT_HTTPPOST,post);
else
{
curl_easy_setopt(curl, CURLOPT_POST,1);
curl_easy_setopt(curl, CURLOPT_COPYPOSTFIELDS , postbuffer.c_str());
}
code = curl_easy_perform(curl);对于返回页面，我们可以和上一篇文章所说那样，设置write的回调函数，写入文件即可：
curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L);
curl_easy_setopt(curl, CURLOPT_URL, url.c_str());
curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1);
curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, writer);
long writer(void *data, int size, int nmemb, string &content)
{
long sizes = size * nmemb;
string temp(data,sizes);
printf("receive data(%d bytes):\r\n%s", sizes, (char*)data );
content += temp;
return sizes;
}
测试：
我们可以用tomcat写一个jsp上传代码测试一下，其中使用到了smartUpload组件，代码如下：upload.html
<form action="upload.jsp" method="post" ENCTYPE="multipart/form-data">
输入名称:<input type="type" name="name"><br>
选择要上传的图片:
<input type="file" name="pic">
<input type="submit" value="上传">
</form>
upload.jsp如下:
<jsp:useBean id="smart" scope="page" class="org.lxh.smart.SmartUpload"/>
<%
//上传初始化
smart.initialize(pageContext);
//准备上传
smart.upload();
//保存上传的文件
//smart.save("/upload");
//取得文件的扩展名称
String ext = smart.getFiles().getFile(0).getFileExt();
%>
<%
//String name=request.getParameter("name"); 表单被封装了,不能用这种方法取值.
String name=smart.getRequest().getParameter("name");
%>
//<%=name+"."+ext%>
<% //保存文件,包括改名.
smart.getFiles().getFile(0).saveAs("/upload/"+name+"."+ext);
%>
经测试用libcurl POST文件成功。以上是简单的测试，比较深入的问题还有待进一步研究。
由于我对HTTP协议，WEB这块不是太熟，如果有错误理解不当的地方，还请指正，欢迎大家和我探讨，谢谢！