Microsoft bot framework : How to define the image path which exists in the solution itself - bots

Question

I have stored the image inside the project itself, now I would like to display the image on the hero card, so I have mentioned the relative path. However the image is not appearing....
List<CardImage> cardImages = new List<CardImage>();
cardImages.Add(new CardImage(url: "~/duck-on-a-rock.jpg", alt:"image1"));
But when I referred the image from some website and mention the same path on the page like below that time the image is appearing.
List<CardImage> cardImages = new List<CardImage>();
cardImages.Add(new CardImage(url: "http://www.publicdomainpictures.net/pictures/30000/t2/duck-on-a-rock.jpg", alt:"image1"));
Is it not possible to keep the image inside the project folder?

Answer 1

This is a super old question, but google me brought here nonetheless. The solution I came across was to create a data url for your local resource. In node.js:
const imageData = fs.readFileSync(path.join(__dirname, '../resources/logo.png'));
const base64Image = Buffer.from(imageData).toString('base64');
const inlinePng = {
name: 'logo.png',
contentType: 'image/png',
contentUrl: `data:image/png;base64,${ base64Image }`
};
With an svg, you can skip the base64 encode:
const svgData = fs.readFileSync(path.join(__dirname, './resources/logo.svg'));
const inlineSvg = {
name: 'logo',
contentType: 'image/svg',
contentUrl: `data:image/svg+xml;utf8,${ svgData }`,
};
See Microsoft's docs for reference and C# samples.

Answer 2

Using DI approach: Pass one extra IHostingEnvironment variable to your dialog constructor.
public DialogBot(ConversationState conversationState, T dialog, ConcurrentDictionary<string, ConversationReference> conversationReferences, IHostingEnvironment env)
{
_conversationReferences = conversationReferences;
_conversationState = conversationState;
_dialog = dialog;
_env = env;
}
And later you can use _env.WebRootPath to access your local storage (for bot emulator) or use environmental variable WEBSITE_HOSTNAME if you run bot in azure.
private async Task SendWelcomeCardAsync(ITurnContext turnContext, CancellationToken cancellationToken)
{
var card = new HeroCard();
card.Title = "Welcome to Bot Framework!";
var host = new Uri(Environment.GetEnvironmentVariable("WEBSITE_HOSTNAME") != null ? ("https://" + Environment.GetEnvironmentVariable("WEBSITE_HOSTNAME")) : _env.WebRootPath + "/");
var img = new Uri(host, "MyImage.jpg");
card.Images = new List<CardImage>() { new CardImage(img.AbsoluteUri) };
var response = MessageFactory.Attachment(card.ToAttachment());
await turnContext.SendActivityAsync(response, cancellationToken);
}
I simply dropped MyImage.jpg image to wwwroot project folder and marked it as Content