Hey
I'm currently working on posting a file from a C# application to an image host (KalleLoad.net - with the owners consent, obviously).
I've gotten the actual posting of the request to work, but it's not returning what I expected. The owner of the upload site has provided me with an API (of sorts) which will return some XML with the URLs if I post the data to a certain address. I can successfully post the data and get a response from the server, however it is simply returning the code for the home page instead of the XML. I cannot understand why this is so.
I've also tried posting data to a simple PHP page on my local server and it too returns the code for the page, instead of what I instructed the page to return on post.
Below is the entirety of my current class for sending the data. I have also been comparing the headers I have been sending from my application with those that firefox is sending for the last half-hour and I can see no real game-changing differences between them (as far as I'm aware).
Any help on this would be fantastic and graciously received.
Regards, Andy Hunt
using System;
using System.Net;
using System.Text;
using System.IO;
using System.Collections;
using System.Collections.Generic;
using System.Drawing;
namespace Skimpt_3._0
{
class PostFile
{
private Hashtable FormElements;
private HttpWebRequest Request;
private MemoryStream FileStream;
private string CONTENT_BOUNDARY = "---------------------------265001916915724";
public string ContentMIMEType;
public string FormURL;
public string FileName;
public string Response;
public string FileBoxName;
//private int BufferSize;
public PostFile(string Url, string strFileName)
{
FormElements = new Hashtable();
FormURL = Url;
Request = (HttpWebRequest)WebRequest.Create(Url);
//BufferSize = 10240;
FileStream = new MemoryStream();
FileName = strFileName;
}
public void Send(Image image)
{
//Assign the request here too, just in case
Request = (HttpWebRequest)WebRequest.Create(FormURL);
Request.Method = "POST";
Request.AllowWriteStreamBuffering = true;
Request.ProtocolVersion = HttpVersion.Version11;
Request.Headers.Add("Cache-Control", "no-cache");
Request.KeepAlive = true;
Request.ContentType = "multipart/form-data; boundary=---------------------------265001916915724";
StartFileStream(FileStream);
//Must be done in this order for stream to write properly:
//----
//Form elements
//File header
//Image
//File trailer
//----
WriteStringToStream(FileStream, GetFormElements());
WriteImageToStream(FileStream, image, FileName);
CloseStream(FileStream);
byte[] FileByteArray = FileStream.ToArray();
Request.ContentLength = FileByteArray.Length;
Stream PostingStream = Request.GetRequestStream();
PostingStream.Write(FileByteArray, 0, FileByteArray.Length);
WebResponse resp = (HttpWebResponse)Request.GetResponse();
StreamReader SR = new StreamReader(resp.GetResponseStream());
PostingStream.Close();
FileStream.Close();
Request.GetRequestStream().Close();
Response = SR.ReadToEnd();
Request = null;
}
private void CloseStream(MemoryStream FileStream)
{
byte[] BytesToWrite = Encoding.ASCII.GetBytes(CONTENT_BOUNDARY);
FileStream.Write(BytesToWrite, 0, BytesToWrite.Length);
}
private void StartFileStream(MemoryStream FileStream)
{
// \r\n = new line
string str = "POST " + FormURL +"Content-Type: multipart/form-data; boundary="+CONTENT_BOUNDARY+" \r\n \r\n" + CONTENT_BOUNDARY;
byte[] BytesToWrite = Encoding.ASCII.GetBytes(str);
FileStream.Write(BytesToWrite, 0, BytesToWrite.Length);
}
private Byte[] ConvertImageToByteArray(Image img)
{
//Method taken from http://www.csharp-station.com/Articles/Thumbnails.aspx and adapted
MemoryStream memStream = new MemoryStream();
img.Save(memStream, System.Drawing.Imaging.ImageFormat.Png);
byte[] byteArray = new Byte[memStream.Length];
memStream.Position = 0;
memStream.Read(byteArray, 0, (int)memStream.Length);
return byteArray;
}
public void AddFormElement(string ElementName, string ElementValue)
{
FormElements[ElementName] = ElementValue;
}
private string GetFormElements()
{
string str = "";
IDictionaryEnumerator myEnumerator = FormElements.GetEnumerator();
while (myEnumerator.MoveNext())
{
str += CONTENT_BOUNDARY + "\r\n" +
"Content-Disposition: form-data; name=" + myEnumerator.Key +
"\r\n\r\n" +
myEnumerator.Value +"\r\n";
}
return str;
}
private void WriteStringToStream(System.IO.MemoryStream stream, string String)
{
byte[] PostData = System.Text.Encoding.ASCII.GetBytes(String);
stream.Write(PostData, 0, PostData.Length);
}
private void WriteImageToStream(System.IO.MemoryStream Stream, Image img, string FileName)
{
byte[] ByteArray = ConvertImageToByteArray(img);
string head = CONTENT_BOUNDARY + "\r\n" +
"Content-Disposition: form-data; name=\"" + FileBoxName + "\"; filename=\"" + FileName + "\"\r\n" +
"Content-Type: " + ContentMIMEType + "\r\n\r\n";
byte[] header = Encoding.ASCII.GetBytes(head);
Stream.Write(header, 0, header.Length);
Stream.Write(ByteArray, 0, ByteArray.Length);
}
}
}