Hey Ronald,

I have spent the last few hours trying to do exactly what you say isn't possible, pre-populate a Nested Content property from the EditorModelEventManager_SendingContentModel event.

I am populating in the same way as I have previously done with IContent but no matter what I try (even taking the generated JSON output when saving through the backoffice), it just won't populate.

testValues.Add(new Dictionary<string, object>()
{
    { "key", Guid.NewGuid().ToString() },
    { "name", "Test string value" },
    { "ncContentTypeAlias", "nCTest" },
    { "testString", "Test string value" }
});
property = JsonConvert.SerializeObject(testValues);

Is there a reason why this isn't possible/an alternative route? I am thinking it's gonna have to be a custom property editor.

When creating a new doc type, I need to pre-populate a nested content property with data from elsewhere in the system, so doing this on a NC default value/saving event isn't a solution unfortunately.

Any thoughts/ideas you have would be greatly appreciated.

Hi Ronald,

I have actually managed to get this working for Nested Content.

The property when sent to the backoffice is a ContentPropertyBasic model and the value is expecting an object, not json, so simply passing the Nested Content object without serializing works.

For anyone coming to this wanting to do the same thing, build your Nested Content object:

nestedContent.Add(new Dictionary<string, object>()
{
    { "key", Guid.NewGuid().ToString() },
    { "ncContentTypeAlias", "ncAlias" },
    { "name", "NC item name" },
    { "ncPropertyAlias", "Property value" }
});

Find your property and set the value:

var property = content.Tabs.SelectMany(tab => tab.Properties).FirstOrDefault(property => property.Alias.InvariantEquals(propertyAlias));
property.Value = nestedContent;

Your Nested Content property will now be pre-populated before saving the node.