TwitterSharp 0.0.0-alpha

To begin with, please go to the Twitter Developer Portal and create a new application

Get a tweet from its ID

var client = new TwitterSharp.Client.TwitterClient(bearerToken);
var answer = await client.GetTweetsByIdsAsync("1389189291582967809");
Console.WriteLine(answer[0].Text); // たのしみ！！\uD83D\uDC93 https://t.co/DgBYVYr9lN

Get an user from its username

var client = new TwitterSharp.Client.TwitterClient(bearerToken);
var answer = await client.GetUsersAsync("theindra5");
Console.WriteLine(answer[0].Id); // 1022468464513089536

Get latest tweets from an user id

var client = new TwitterSharp.Client.TwitterClient(bearerToken);
// You can get the id using GetUsersAsync
var answer = await client.GetTweetsFromUserIdAsync("1109748792721432577");
for (int i = 0; i < answer.Length; i++)
{
    Console.WriteLine($"Tweet n°{i}:\n{answer[i].Text}\n\n");
}

Follow users and get all new tweets

var client = new TwitterSharp.Client.TwitterClient(bearerToken);

// Subscribe to 5 Twitter accounts
var request = new TwitterSharp.Request.StreamRequest(
    Expression.Author("moricalliope") // using TwitterSharp.Rule;
        .Or(
            Expression.Author("takanashikiara"),
            Expression.Author("ninomaeinanis"),
            Expression.Author("gawrgura"),
            Expression.Author("watsonameliaEN")
        )
);
await client.AddTweetStreamAsync(request); // Add them to the stream

// We display all the subscriptions we have
var subs = await client.GetInfoTweetStreamAsync();
Console.WriteLine("Subscriptions: " + string.Join("\n", subs.Select(x => x.Value.ToString())));

// NextTweetStreamAsync will continue to run in background
Task.Run(async () =>
{
    // Take in parameter a callback called for each new tweet
    // Since we want to get the basic info of the tweet author, we add an empty array of UserOption
    await client.NextTweetStreamAsync((tweet) =>
    {
        Console.WriteLine($"From {tweet.Author.Name}: {tweet.Text}");
    }, Array.Empty<UserOption>());
});