private async Task LoadCard()
{
if (Entities?.UrlEntities == null)
{
return;
}
TwitterCard card = null;
foreach (var url in Entities.UrlEntities.Select(u => u.ExpandedUrl))
{
card = await CardExtractor.ExtractCard(new Uri( url ));
if (card != null)
{
break;
}
}
if (card != null)
{
Card = new CardViewModel(card);
HasCard = Card.Card.IsValid;
}
else
{
Card = null;
HasCard = false;
}
}
public void TitleIsRequired()
{
// Arrange
var meta = new Dictionary <string, string>
{
{ "twitter:card", "summary" },
{ "twitter:description", "desc" },
{ "twitter:site", "site" }
};
var metaFull = new Dictionary <string, string>
{
{ "twitter:card", "summary" },
{ "twitter:description", "desc" },
{ "twitter:site", "site" },
{ "twitter:title", "title" }
};
// Act
var card = new TwitterCard(meta);
var validCard = new TwitterCard(metaFull);
// Assert
Assert.IsFalse(card.IsValid);
Assert.IsTrue(validCard.IsValid);
}
public void CardWithoutDataIsInvalid()
{
// Arrange
var meta = new Dictionary <string, string>();
// Act
var card = new TwitterCard(meta);
// Assert
Assert.IsFalse(card.IsValid);
}
public void EmptyHostDoesNotCrash()
{
// Arrange
var card = new TwitterCard(new Dictionary <string, string>());
var vm = new CardViewModel(card);
// Act
string url = null;
var ex = ExceptionAssert.Catch <NullReferenceException>(() => url = vm.DisplayUrl);
// Assert
Assert.IsNull(ex);
Assert.AreEqual(string.Empty, url);
}
public void UnknownTypeIsInvalid()
{
// Arrange
var meta = new Dictionary <string, string>
{
{ "twitter:site", "site" },
{ "twitter:title", "title" },
{ "twitter:description", "desc" },
{ "twitter:card", "summary_123" }
};
// Act
var card = new TwitterCard(meta);
// Assert
Assert.IsFalse(card.IsValid);
}
public CardViewModel(TwitterCard card)
{
Card = card;
}
/// <summary>
/// Creates a string containing the Twitter card meta tags. <see cref="TwitterCard"/> for more information.
/// </summary>
/// <param name="htmlHelper">The HTML helper.</param>
/// <param name="twitterCard">The Twitter card metadata.</param>
/// <returns>The meta tags.</returns>
public static IHtmlString TwitterCard(this HtmlHelper htmlHelper, TwitterCard twitterCard)
{
return twitterCard;
}
