Hi Andrew

You need to generate the JSON blob required by Nested Content yourself. It should be an array of objects, and each object must have the properties key, ncContentTypeAlias, and the properties of your desired document type.

I have previously done like this

var contentItem = ContentService.GetById(1);

var nestedContentValue = new JArray();
// you can add a loop here, if you need multiple nested items
var nestedContentItem = new JObject();

// you need to add a Guid as a key to your item
nestedContentItem .Add("key", Guid.NewGuid().ToString());

// and the desired doctype
nestedContentItem.Add("ncContentTypeAlias", "myNestedType");

// add the values for each property of your doctype
nestedContentItem.Add("myPropertyAlias", "some property value");

// finally, add you nestedContentItem, to your nestedContentValue
nestedContentValue.Add(nestedContentItem);

// then set the value of your IContent contentItem
contentItem.SetValue("nestedContentProperty", JsonConvert.SerializeObject(nestedContentValue));

Hope it helps :)

thanks Søren :D

i was just as interested to know how i should identify pages that contain the said doctype in their NestedContent property (your first line of code). Does anyone know convenient/efficient ways of doing that? thank you

var contentService = Current.Services.ContentService;
            var regulationNode = contentService.GetById(nodeID);
            var node = Umbraco.Content(nodeID);
            var downloadItems = node.Value<IEnumerable<IPublishedElement>>("addRegulationItems", culture: culture, fallback: Fallback.ToDefaultValue, defaultValue: null);
            var ncItems = new List<ListingItem>();
            int count = 0;
            try
            {
                if (downloadItems != null && downloadItems.Any())
                {
                    foreach (var content in downloadItems)
                    {
                        var ncItem = new ListingItem();
                        ncItem.title = content.Value<string>("title", culture: culture, fallback: Fallback.ToDefaultValue, defaultValue: null);
                        ncItem.description = content.Value<string>("description", culture: culture, fallback: Fallback.ToDefaultValue, defaultValue: null);
                        var downloadFile = content.GetProperty("downloadFile").GetSourceValue(culture: culture).ToString();
                        ncItem.downloadFile = downloadFile;
                        ncItem.uploadDate = content.Value<DateTime?>("uploadDate", culture: culture, fallback: Fallback.ToDefaultValue, defaultValue: null);
                        ncItem.key = content.Key.ToString();
                        ncItem.ncContentTypeAlias = content.ContentType.Alias;
                        var totalDownloads = content.Value<int>("totalDownloads");
                        if (ncItem.key == item)
                        {
                            if (totalDownloads > 0)
                            {
                                count = totalDownloads + 1;
                                ncItem.totalDownloads = count.ToString();
                            }
                            else
                            {
                                count = 1;
                                ncItem.totalDownloads = 1.ToString();
                            }
                        }
                        else
                        {
                            ncItem.totalDownloads = content.Value<string>("totalDownloads");
                        }
                        ncItems.Add(ncItem);
                    }
                    var ncItemString = Newtonsoft.Json.JsonConvert.SerializeObject(ncItems);
                    regulationNode.SetValue("addRegulationItems", ncItemString, culture: culture);
                    contentService.SaveAndPublish(regulationNode);
                    return Json(new { stat = true, count = count }, JsonRequestBehavior.AllowGet);
                }
            }

Hope this helps. You can fetch the key variable from each nested content element and update that speific element.

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