Sitecore custom index field

child items custom index field

namespace MyNamespace
{
    public class IndexChildContent : IComputedIndexField
    {
        /// <inheritdoc />
        public string FieldName { get; set; }
        /// <inheritdoc />
        public string ReturnType { get; set; }

        /// <inheritdoc />
        public object ComputeFieldValue(IIndexable indexable)
        {
            Item item = indexable as SitecoreIndexableItem;

            if (item != null)
            {
                try
                {
                    var indexedContent = string.Empty;
                    var components = item.Children.Where(x => x.TemplateID == new Sitecore.Data.ID("{7D396D96-54D5-4F2A-B552-4177F1831D41}")).FirstOrDefault(); // datasource template

                    if (components != null)
                    {
                        var dataitems = components.Children.Where(x => x.TemplateID == new Sitecore.Data.ID("{70BB078F-C283-40F3-AD63-962780070879}") || x.TemplateID == new Sitecore.Data.ID("{64E5D773-A6CB-46F6-84FE-93FE2C9A79CB}")); // Rich text template types

                        foreach (var content in dataitems)
                        {
                            var indexField = content.Fields["Text"];

                            if (indexField.HasValue)
                            {
                                indexedContent = indexedContent + Sitecore.StringUtil.RemoveTags(indexField.Value);
                            }
                        }

                        return indexedContent;
                    }
                }
                catch (Exception)
                {
                    return null;
                }
            }
           
            return null; // Return null if nothing to index
        }
    }
}

Lucene index

<fields hint="raw:AddComputedIndexField">
   <field fieldName="childcontent" storageType="yes" indexType="untokenized"
    patch:after="field[last()]">MyNamespace.IndexChildContent, MyNamespace</field>
</fields>