Develop Reference

Proper way to handle the ampersand character in JSON string send to REST web service

OK,
I am using the System.Runtime.Serialization and the DataContractJsonSerialization.
The problem is that in the request I send a value of a property with the & character. Say, AT&T, and I get a response with error: Invalid JSON Data.
I thought that the escaping would be done inside the library but now I see that the serialization is left untouched the ampersand & character.
Yes, for a JSON format this is valid.
But it will be a problem to my POST request since I need to send this to a server that if contains an ampersand will response with error, hence here I am.
HttpUtility.HtmlEncode is in the System.Web library and so the way to go is using Uri.EscapeUriString. I did this to try, but anyway, and without it all requests are working fine, except an ampersand is in a value.
EDIT: HttpUtility class is ported to the Windows Phone SDK but the prefer way to encode a string should be still Uri.EscapeUriString.
First thought was to get hands dirty and start replacing the special character which would cause a problem in the server, but, I wonder, is there another solution I should do, that it would be efficient and 'proper'?
I should tell that I use
// Convert the string into a byte array.
byte[] postBytes = Encoding.UTF8.GetBytes(data);
To convert the JSON to a byte[] and write to the Stream.
And,
request.ContentType = "application/x-www-form-urlencoded";
As the WebRequest.ContentType.
So, am I messed up for a reason or something I miss?
Thank you.

The problem was that I was encoding the whole request string including the key.
I had a request data={JSON} and I was formatting it, but the {JSON} part should only be encoded.
string requestData = "data=" + Uri.EncodeDataString(json) // worked perfect!
Stupid hole to step into.

Have you tried replacing the ampersand with & for the POST?

Error converting urlencode from PHP to C#

I have a class in PHP that encodes this code "?�m�U", using urlencode(), resulting in "%3F%B6%16m%BEU". However, when I try to encode with c# uisng HttpUtility.UrlEncode(), the result is not the same. The method in c# has a second parameter "Encoding.SOMETHING". I've tried each one of the possible paramaters, but it still doesn't work.
Does anyone know how I can fix this?

This one should work:
string utf8Encoded = System.Web.HttpUtility.UrlEncode(YOURURL, Encoding.UTF8);

How to convert a string to a url encoded

I want to be able to convert for example ™ to %99 but i dont know what encoding is that
I tried looking at httputility class but i dont get %99 i get other wierd signs can you please help me? thanks
Im using C#
I want to do that so my the login would work with all chars like ™ im using http post method for a vb forum i need first to correct the encoding
EDIT : Not sure but can i just change the Content-Type : application/x-www-form-urlencoded
to something that accepts signs like trademark so it would work?

From the subject it seems that you are trying to encode given string to url string, e.g. changing something like user#email.com to user%40email.com so it can be in a url http://www.example.com?email=user%40gmail.com
Can you provide a little more information?
If you are trying to pass the string through a URL, than I highly recommend the HttpUtility.UrlEncode method to be on the safe side.

C#, UTF-8 and encoding characters

This is a shot-in-the-dark, and I apologize in advance if this question sounds like the ramblings of a madman.
As part of an integration with a third party, I need to UTF8-encode some string info using C# so I can send it to the target server via multipart form. The problem is that they are rejecting some of my submissions, probably because I'm not encoding their contents correctly.
Right now, I'm trying to figure out how a dash or hyphen -- I can't tell which it is just by looking at it -- is received or interpreted by the target server as ?~#~S (yes, that's a 5-character string and is not your browser glitching out). And unfortunately I don't have a thorough enough understanding of Encoding.UTF8.GetBytes() to know how to use the byte array to begin identifying where the problem might lie.
If anybody can provide any tips or advice, I would greatly appreciate it. So far my only friend has been MSDN, and not much of one at that.
UPDATE 1: After some more digging around, I discovered that using System.Web.HttpUtility.UrlEncode()to encode an EM DASH character ("—") will hex-encode it into "%e2%80%94".
I'm currently sending this info in aHttpWebRequestpost, with a content type of "application/x-www-form-urlencoded" -- could this be what's causing the problem? And if so, what is the proper way to encode a series of name-value pairs whose values may contain Unicode characters, such that it will be understood by a server expecting a UTF-8 request?

byte[] test = System.Text.Encoding.UTF8.GetBytes("-");
Should give you
test[0] = 0x2D (45 as integer).
Verify that your sending 0x2D to the target server.

You may need to add a "charset=utf-8" parameter to your Content-Type header. You may also want to have a Content-Encoding header to set your encoding. The headers should contain the following:
Content-Type: multipart/form-data; charset=utf-8
Otherwise, the web server won't know your bytes are UTF-8 bytes, so it will misinterpret them.

Url encoded characters, ViewState and byte[] arrays oh my

I am trying to throw together a screen scraper and keep getting invalid viewstate issues. It appears that during the System.Net.WebClient download of data or the System.Text.UTF8Encoding.Default.GetString call to convert the byte array returned by the WebClient DownloadData call to a string - that strings which match url character codes are being converted.
ie
Url encoded characters strings like %2B are being converted to their normal characters (+ for %2B).
Is this happening in the WebClient class? Is it the way I am converting the byte array to a string?
EDIT:
Based on suggestions I tried changing to the DownloadString call from the WebClient class and the resulting string has converted the character codes to the specific character so it appears WebClient is the culprit.
EDIT 2:
Solved. By making a call to System.Web.HttpUtility.UrlEncode I was able to convert the + back to %2B before sending the viewstate string back up to the server in subsequent requests. I am still at a loss as to where and why the problem was occurring but the server was expecting a viewstate string that contained ...%2B... and was getting ...+... and determining the viewstate to be invalid and throwing the exception. Kudos to Jon & Henk for forcing me to rethink my assumptions.

If you use System.Text.UTF8Encoding.Default then you're not using UTF-8 - you're using the default encoding for the system. It's equivalent to Encoding.Default, but in a more confusing form. Use Encoding.UTF8 to get a UTF-8 encoding... or use WebClient.DownloadString as Henk suggested.
On the other hand, it's not clear what you're trying to download. If you're trying to download geuinely binary data then you shouldn't be trying to convert it to a string at all.
It would help if you would clarify you question - try to provide a lot more context about what's making the requests, what's having problems, etc.

And what happened if you just use WebClient.DownloadString() instead of opening a binary stream?