Display Welcome Message in v4 Bot Framework Bot (C# + .Net Core Web Application)

Question

I had created a bot with v3 (C#) SDK and the welcome message used to work just fine without any sweat. And it still does for me in production. The code is handled in HandleS

Answer 1

tdurnford's answer didn't work for me. I'm using a new v4 bot (no migration) and embedding iframe into Sharepoint. OnEventActivityAsync just doesn't trigger. I get a conversation update with my bot being a MembersAdded so I did this:

    protected override async Task OnConversationUpdateActivityAsync(ITurnContext turnContext, CancellationToken cancellationToken)
    {
        await base.OnConversationUpdateActivityAsync(turnContext, cancellationToken);

        if (turnContext.Activity.ChannelId == "webchat" && turnContext.Activity.MembersAdded?.FirstOrDefault(m => m?.Name == Configuration["BotName"]) != null)
        {
            await SendWelcomeMessageAsync(turnContext, cancellationToken);
        }
    }

BotName is "Bot" for local development and the app name for azure deployed apps. SendWelcomeMessage is my own method. Also as above, I added a check in OnMembersAddedAsync:

protected override async Task OnMembersAddedAsync(IList membersAdded, ITurnContext turnContext, CancellationToken cancellationToken)
    {
        if (turnContext.Activity.ChannelId == "webchat" || turnContext.Activity.ChannelId == "directline")
            return;

        foreach (var member in membersAdded)
        {
            // Greet anyone that was not the target (recipient) of this message.
            // To learn more about Adaptive Cards, see https://aka.ms/msbot-adaptivecards for more details.
            if (member.Id != turnContext.Activity.Recipient.Id)
            {
                await SendWelcomeMessageAsync(turnContext, cancellationToken);
            }
        }
    }