Sitecore: base template item of a page

Question

I have a page Item in Sitecore, and I know it is derived from a certain base template. I have that base template ID, but I want to get the instance of this base template that is part of my page. I want it as an item, so for example I can get the ID of the template internal of the page.

To be more clear:

• Page called A1 of template A
• Template A has as base template the template B
• B is part of page A1 as an instance called B1 (field values specific for the page A1)

How can I get B1 as stand alone Item/ID?
Any help is appreciated.
Thanks.

Answer 1

Not really sure what you mean? why would you want to get the instance of an inheriting template? the item would have all fields you've inherited available anyway via item.fields[templateBFieldId].Value

You could do something like check if the current item inherits from that template.. so something like:

public static bool InheritsFrom(this Item item, ID templateId)
    {
        return item.Template.DoesTemplateInheritFrom(templateId);
    }

    public static bool DoesTemplateInheritFrom(this TemplateItem template, ID templateId)
    {
        if (template == null || templateId.IsNull)
            return false;
        if (!(template.ID == templateId))
            return template.DoesTemplateInheritFrom(TemplateManager.GetTemplate(templateId, template.Database));
        return true;
    }

private static bool DoesTemplateInheritFrom(this TemplateItem template, Template baseTemplate)
        {
            if (baseTemplate == null)
                return false;

            return TemplateManager.GetTemplate(template.ID, template.Database).DescendsFromOrEquals(baseTemplate.ID);
        }

Answer 2

I was getting confused about the contents of the''yml. There is no instance of the base template within the page item