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HttpWebRequest 上传文件

2011-09-13 14:33  LoujaDy  阅读(7323)  评论(1编辑  收藏  举报
            //边界
            string boundary = DateTime.Now.Ticks.ToString("x");
            HttpWebRequest uploadRequest 
= (HttpWebRequest)WebRequest.Create(url);//url为上传的地址
            uploadRequest.ContentType 
= "multipart/form-data; boundary=" + boundary;
            uploadRequest.Method 
= "POST";
            uploadRequest.Accept 
= "*/*";
            uploadRequest.KeepAlive 
= true;
            uploadRequest.Headers.Add(
"Accept-Language""zh-cn");
            uploadRequest.Headers.Add(
"Accept-Encoding""gzip, deflate");
            uploadRequest.Credentials 
= System.Net.CredentialCache.DefaultCredentials;
            uploadRequest.Headers[
"Cookie"= cookies;//上传文件时需要的cookies

            WebResponse reponse;
            
//创建一个内存流
            Stream memStream = new MemoryStream();

            
//确定上传的文件路径
            if (!String.IsNullOrEmpty(file))
            {
                boundary 
= "--" + boundary;

                
//添加上传文件参数格式边界
                string paramFormat = boundary + "\r\nContent-Disposition: form-data; name=\"{0}\";\r\n\r\n{1}\r\n";
                NameValueCollection param 
= new NameValueCollection();
                param.Add(
"fname", Guid.NewGuid().ToString() + Path.GetExtension(file));
               
                
//写上参数
                foreach (string key in param.Keys)
                {
                    
string formitem = string.Format(paramFormat, key, param[key]);
                    
byte[] formitembytes = System.Text.Encoding.UTF8.GetBytes(formitem);
                    memStream.Write(formitembytes, 
0, formitembytes.Length);
                }

                
//添加上传文件数据格式边界
                string dataFormat = boundary + "\r\nContent-Disposition: form-data; name=\"{0}\";filename=\"{1}\"\r\nContent-Type:application/octet-stream\r\n\r\n";
                
string header = string.Format(dataFormat, "Filedata", Path.GetFileName(file));
                
byte[] headerbytes = System.Text.Encoding.UTF8.GetBytes(header);
                memStream.Write(headerbytes, 
0, headerbytes.Length);

                
//获取文件内容
                FileStream fileStream = new FileStream(file, FileMode.Open, FileAccess.Read);
                
byte[] buffer = new byte[1024];
                
int bytesRead = 0;

                
//将文件内容写进内存流
                while ((bytesRead = fileStream.Read(buffer, 0, buffer.Length)) != 0)
                {
                    memStream.Write(buffer, 
0, bytesRead);
                }
                fileStream.Close();

                
//添加文件结束边界
                byte[] boundarybytes = System.Text.Encoding.UTF8.GetBytes("\r\n\n" + boundary + "\r\nContent-Disposition: form-data; name=\"Upload\"\r\n\nSubmit Query\r\n" + boundary + "--");
                memStream.Write(boundarybytes, 
0, boundarybytes.Length);

                
//设置请求长度
                uploadRequest.ContentLength = memStream.Length;
                
//获取请求写入流
                Stream requestStream = uploadRequest.GetRequestStream();
               

                
//将内存流数据读取位置归零
                memStream.Position = 0;
                
byte[] tempBuffer = new byte[memStream.Length];
                memStream.Read(tempBuffer, 
0, tempBuffer.Length);
                memStream.Close();

                
//将内存流中的buffer写入到请求写入流
                requestStream.Write(tempBuffer, 0, tempBuffer.Length);
                requestStream.Close();
            }

            
//获取到上传请求的响应
            reponse = uploadRequest.GetResponse();

作者:Louja
出处:http://loujady.cnblogs.com
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