Question

using Orchard.ContentManagement;
using Orchard.ContentManagement.Drivers;

namespace Orchard.Webshop.Drivers {
    public class ProductDriver : ContentPartDriver<ProductPart> {
        protected override DriverResult Editor(ProductPart part, dynamic shapeHelper)
        {
            return ContentShape("Parts_Product_Edit", () => shapeHelper.EditorTemplate(TemplateName: "Parts/Product", Model: part, Prefix: Prefix));
        }

        protected override DriverResult Editor(ProductPart part, IUpdateModel updater, dynamic shapeHelper)
        {
            updater.TryUpdateModel(part, Prefix, null, null);
            return Editor(part, shapeHelper);
        }
    }
}

I’ve been searching for what the Prefix does, but haven’t found anything that defines it or explains its purpose. And if the Prefix can be used in methods other than Editor, please feel free to elborate on that as well. Thank you.

Answer 1

It is a string prefix that gets appended to the form field names in of the editor templates. The reason this is needed:

Lets say you create a new content part, named NoobsPart, with a property called “Text”. And in the “N00b” content type that contains N00bsPart, you also attach a BodyPart. The BodyPart also has a property called “Text”. The html field names of BodyPart and N00bsPart would clash with each other on postback. The prefix solves the problem of the field names clashing. Generally the prefix can be set to the part name to disambiguate and avoid the clash. I’m not sure if the Prefix is used anywhere else, but given the problem it solves, I would think not.

Following examples in Orchard core code, I usually set prefix as a class property in the driver:

using Orchard.ContentManagement;
using Orchard.ContentManagement.Drivers;

namespace Orchard.Webshop.Drivers {
    public class ProductDriver : ContentPartDriver<ProductPart> {
        protected override string Prefix { get { return "ProductPart"; } }
        protected override DriverResult Editor(ProductPart part, dynamic shapeHelper)
        {
            return ContentShape("Parts_Product_Edit", () => shapeHelper.EditorTemplate(TemplateName: "Parts/Product", Model: part, Prefix: Prefix));
        }

        protected override DriverResult Editor(ProductPart part, IUpdateModel updater, dynamic shapeHelper)
        {
            updater.TryUpdateModel(part, Prefix, null, null);
            return Editor(part, shapeHelper);
        }
    }
}