C#实现HTTP上传文件的方法

/// <summary>
/// http上传文件
/// </summary>
public static string httpuploadfile(string url, string path)
{
    // 设置参数
    httpwebrequest request = webrequest.create(url) as httpwebrequest;
    cookiecontainer cookiecontainer = new cookiecontainer();
    request.cookiecontainer = cookiecontainer;
    request.allowautoredirect = true;
    request.method = "post";
    string boundary = datetime.now.ticks.tostring("x"); // 随机分隔线
    request.contenttype = "multipart/form-data;charset=utf-8;boundary=" + boundary;
    byte[] itemboundarybytes = encoding.utf8.getbytes("\r\n--" + boundary + "\r\n");
    byte[] endboundarybytes = encoding.utf8.getbytes("\r\n--" + boundary + "--\r\n");

    int pos = path.lastindexof("\\");
    string filename = path.substring(pos + 1);

    //请求头部信息
    stringbuilder sbheader = new stringbuilder(string.format("content-disposition:form-data;name=\"file\";filename=\"{0}\"\r\ncontent-type:application/octet-stream\r\n\r\n", filename));
    byte[] postheaderbytes = encoding.utf8.getbytes(sbheader.tostring());

    filestream fs = new filestream(path, filemode.open, fileaccess.read);
    byte[] barr = new byte[fs.length];
    fs.read(barr, 0, barr.length);
    fs.close();

    stream poststream = request.getrequeststream();
    poststream.write(itemboundarybytes, 0, itemboundarybytes.length);
    poststream.write(postheaderbytes, 0, postheaderbytes.length);
    poststream.write(barr, 0, barr.length);
    poststream.write(endboundarybytes, 0, endboundarybytes.length);
    poststream.close();

    //发送请求并获取相应回应数据
    httpwebresponse response = request.getresponse() as httpwebresponse;
    //直到request.getresponse()程序才开始向目标网页发送post请求
    stream instream = response.getresponsestream();
    streamreader sr = new streamreader(instream, encoding.utf8);
    //返回结果网页（html）代码
    string content = sr.readtoend();
    return content;
}

using system;
using system.web;

namespace swx
{
    public partial class test2 : system.web.ui.page
    {
        protected void page_load(object sender, eventargs e)
        {
            httppostedfile file = request.files[0];
            file.saveas(mappath("\\uploadfile\\" + file.filename));
            response.write("success\r\n");
        }
    }
}