Console application only sending first 46 characters in a POST request

Question

I am building a console application that gathers some data and then sends it to a php page through a POST request. This is my C# code:

HttpWebRequest Request = (HttpWebRequest)WebRequest.Create("http://localhost/log.php");
Request.Method = "POST";
Request.ContentType = "application/x-www-form-urlencoded";
string PostData = "data=" + UserOutput;
Request.ContentLength = PostData.Length;

StreamWriter stOut = new StreamWriter(Request.GetRequestStream(), System.Text.Encoding.ASCII);
stOut.Write(PostData);
stOut.Close();

And the PHP page (log.php):

<?php

file_put_contents('log.txt', $_POST['data']);

?>

Note I am only using file_put_contents to test if everything works OK, it is not what I want to end up doing.

The length of the post data to send is over 2,000 characters long, and the correct content length is returned by Request.ContentLength = PostData.Length;, so that's not the problem. But whenever I try this it is only sending the first 46 characters of my POST data.

I do have to admit at this point that I copied most of the code, as I am not very experienced in C#.

Any help would be great, thanks.

Answer 1

Is the 47th character "&" by any chance? You've claimed that your data is URL-encoded, but you haven't done any URL-encoding in the code you've provided. If there's an "&" that would indicate to PHP that it was about to accept a new form parameter...

One way to verify this (apart from using HttpUtility.UrlEncode) would be to use Fiddler or Wireshark to see what's actually going on at the network level.

Answer 2

The Close() should handle it, but you may want to try a .Flush() just before that.

Answer 3

If you're only sending one big blob of data, it would be a better strategy to omit the Content-type header and make PostData == UserOutput.

You could then save it with

$s = fopen("php://input", "r");
file_put_contents('log.txt', $s);