Glass Mapper doesn't return null?

Question

var model = GetContextItem<ICmsModel>();

I noticed that glass doesn't return null if ICmsModel is not derived from the Context Item...

In this example, I'd expect glass to try and map it, but what if ICmsModel isn't derived from the Context Item. Is there a way glass can tell me? I thought glass would return null if it can't map, but it doesn't, the object is instantiated but the fields are null.

Does glass offer any methods to help achieve what I want?

Answer 1

You need to set the EnforceTemplate setting when mapping your interface to either SitecoreEnforceTemplate.Template or SitecoreEnforceTemplate.TemplateAndBase.

public enum SitecoreEnforceTemplate
{
    /// <summary>
    /// Will not enforce template check
    /// </summary>
    No,

    /// <summary>
    /// Checks only the items template
    /// </summary>
    Template,

    /// <summary>
    /// Checks the items template and any base templates
    /// </summary>
    TemplateAndBase
}

In most cases you would probably use the TemplateAndBase setting.

Here is how to do it with attribute configuration:

[SitecoreType(TemplateId = "{0EE93413-BD27-44E4-914F-4A94FBED83E9}", EnforceTemplate = SitecoreEnforceTemplate.TemplateAndBase)]
public interface ICmsModel
{
    // ...
}