public override async Task OnEventAsync(ITurnContextThis code checks to see if the incoming activity is a conversation update message, and if so, it sends a welcome message to any members who have been added to the conversation. Overall, the FrameworkMessage class is part of the Bot Builder SDK for .NET, which is published by Microsoft.turnContext, CancellationToken cancellationToken) { if (turnContext.Activity.Name == "ConversationUpdate") { foreach (var member in turnContext.Activity.MembersAdded) { if (member.Id != turnContext.Activity.Recipient.Id) { await turnContext.SendActivityAsync($"Welcome, {member.Name}!"); } } } }