Post tweet

Post_tweet.cs

public void UpdateStatus(string message)
{
	// Application tokens
	const string CONSUMER_KEY = "YOUR_CONSUMER_KEY";
	const string CONSUMER_SECRET = "YOUR_CONSUMER_SECRET";
	// Access tokens
	const string ACCESS_TOKEN = "YOUR_ACCESS_TOKEN";
	const string ACCESS_TOKEN_SECRET = "YOUR_ACCESS_TOKEN_SECRET";
	
	// Common parameters
	const string VERSION = "1.0";
	const string SIGNATURE_METHOD = "HMAC-SHA1";

	// Parameters specific to this request
	var nonce = new Random().Next(0x0000000, 0x7fffffff).ToString("X8");
	var timestamp = ((int) (DateTime.UtcNow - new DateTime(1970, 1, 1)).TotalSeconds).ToString();

	// Prepare the text to sign
	var dataToSign = new StringBuilder();
	dataToSign
		.Append("POST")
		.Append("&")
		.Append("http://api.twitter.com/1/statuses/update.xml".EncodeRFC3986())
		.Append("&");

	// Values to sign: oauth parameters AND request parameters
	var signatureParts = new Dictionary<string, string>
	{
		{"status", message.EncodeRFC3986()},
		{"oauth_version", VERSION},
		{"oauth_consumer_key", CONSUMER_KEY},
		{"oauth_nonce", nonce},
		{"oauth_signature_method", SIGNATURE_METHOD},
		{"oauth_timestamp", timestamp},
		{"oauth_token", ACCESS_TOKEN}
	};

	dataToSign.Append(
		signatureParts
			.OrderBy(x => x.Key)
			.Select(x => "{0}={1}".FormatWith(x.Key, x.Value))
			.Join("&")
			.EncodeRFC3986());

	// Calculate the signature key required to sign the request
	var signatureKey = "{0}&{1}".FormatWith(CONSUMER_SECRET.EncodeRFC3986(), ACCESS_TOKEN_SECRET.EncodeRFC3986());
	var sha1 = new HMACSHA1(Encoding.ASCII.GetBytes(signatureKey));

	var signatureBytes = sha1.ComputeHash(Encoding.ASCII.GetBytes(dataToSign.ToString()));
	var signature = Convert.ToBase64String(signatureBytes);

	// Create and setup the actual request
	var request = (HttpWebRequest) WebRequest.Create("http://api.twitter.com/1/statuses/update.xml");
	request.Method = "POST";
	request.ContentType = "application/x-www-form-urlencoded";

	// Set authorization header
	request.Headers.Add(
		"Authorization",
		new StringBuilder("OAuth ")
			.AppendFormat("{0}=\"{1}\"", "oauth_nonce".EncodeRFC3986(), nonce.EncodeRFC3986()).Append(",")
			.AppendFormat("{0}=\"{1}\"", "oauth_signature_method".EncodeRFC3986(), SIGNATURE_METHOD.EncodeRFC3986()).Append(",")
			.AppendFormat("{0}=\"{1}\"", "oauth_timestamp".EncodeRFC3986(), timestamp.EncodeRFC3986()).Append(",")
			.AppendFormat("{0}=\"{1}\"", "oauth_consumer_key".EncodeRFC3986(), CONSUMER_KEY.EncodeRFC3986()).Append(",")
			.AppendFormat("{0}=\"{1}\"", "oauth_token".EncodeRFC3986(), ACCESS_TOKEN.EncodeRFC3986()).Append(",")
			.AppendFormat("{0}=\"{1}\"", "oauth_signature".EncodeRFC3986(), signature.EncodeRFC3986()).Append(",")
			.AppendFormat("{0}=\"{1}\"", "oauth_version".EncodeRFC3986(), VERSION.EncodeRFC3986())
			.ToString());

	// Add request body with request parameters
	var requestBody = Encoding.ASCII.GetBytes("status={0}".FormatWith(message.EncodeRFC3986()));
	using (var stream = request.GetRequestStream())
		stream.Write(requestBody, 0, requestBody.Length);

	// ... and here we go!
	request.GetResponse();

	// We could analyze the response, but since we'll get an exception if 
        // something fails, we don't need to mess with response content
}
	
public static string Join<T>(this IEnumerable<T> items, string separator)
{
	return string.Join(separator, items.ToArray());
}

public static string FormatWith(this string format, params object[] args)
{
	return string.Format(format, args);
}

// From Twitterizer http://www.twitterizer.net/
public static string EncodeRFC3986(this string value)
{
	if (string.IsNullOrEmpty(value))
		return string.Empty;

	var encoded = Uri.EscapeDataString(value);

	return Regex
		.Replace(encoded, "(%[0-9a-f][0-9a-f])", c => c.Value.ToUpper())
		.Replace("(", "%28")
		.Replace(")", "%29")
		.Replace("$", "%24")
		.Replace("!", "%21")
		.Replace("*", "%2A")
		.Replace("'", "%27")
		.Replace("%7E", "~");
}