Hi!

That is possible! You're going to need to subscribe to INotificationHandler<SendingContentNotification>! It could look something like this:

using System;
using System.Linq;
using Umbraco.Cms.Core.Events;
using Umbraco.Cms.Core.Models.ContentEditing;
using Umbraco.Cms.Core.Notifications;
using Umbraco.Extensions;

namespace Umbraco.Docs.Samples.Web.Notifications
{
    public class EditorSendingContentNotificationHandler : INotificationHandler<SendingContentNotification>
    {
        public void Handle(SendingContentNotification notification)
        {
            if (notification.Content.ContentTypeAlias.Equals("blogpost"))
            {
                // Access the property you want to pre-populate
                // each content item can have 'variations' - each variation is represented by the `ContentVariantDisplay` class.
                // if your site uses variants, then you need to decide whether to set the default value for all variants or a specific variant
                // eg. set by variant name:
                // var variant = notification.Content.Variants.FirstOrDefault(f => f.Name == "specificVariantName");
                // OR loop through all the variants:
                foreach (var variant in notification.Content.Variants)
                {
                    // Check if variant is a 'new variant'
                    // we only want to set the default value when the content item is first created
                    if (variant.State == ContentSavedState.NotCreated)
                    {
                        // each variant has an IEnumerable of 'Tabs' (property groupings)
                        // and each of these contain an IEnumerable of `ContentPropertyDisplay` properties
                        // find the first property with alias 'publishDate'
                        var pubDateProperty = variant.Tabs.SelectMany(f => f.Properties)
                            .FirstOrDefault(f => f.Alias.InvariantEquals("publishDate"));
                        if (pubDateProperty is not null)
                        {
                            // set default value of the publish date property if it exists
                            pubDateProperty.Value = DateTime.UtcNow;
                        }
                    }
                }
            }
        }
    }
}

(I copy pasted this code from the documentation! :P ) You can read more about it here: https://docs.umbraco.com/umbraco-cms/reference/notifications/editormodel-notifications

//Johannes

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