public string OpenGraphTags(string title, string imageUrl, string url, OpenGraphType type)
{
if(string.IsNullOrWhiteSpace(_siteName)
|| string.IsNullOrWhiteSpace(_appId))
{
throw new InvalidOperationException("OpenGraph not initilised, please call Initilise(string sitename, string appId) first.");
}
ValidateOpenGraphParameter(_appId, "appId");
ValidateOpenGraphUrlIsAbsolute(imageUrl, "imageUrl");
ValidateOpenGraphUrlIsAbsolute(url, "url");
return new StringBuilder()
.AddOpenGraphMetaTag("title", title)
.AddOpenGraphMetaTag("type", type.ToString().ToLower())
.AddOpenGraphMetaTag("image", imageUrl)
.AddOpenGraphMetaTag("url", url)
.AddOpenGraphMetaTag("site_name", _siteName)
.AddOpenGraphMetaTag("fb", "app_id", _appId)
.ToString();
}
