How to update HyperLink of an item present inside Document Set in SPOnline

Question

I've an event receiver in Sharepoint on-premise which updates a Hyperlink field with parent document set Url when a new item is added/updated.

Below is the code works good for me in SharePoint on-premise. How to perform the same step in SharePoint Online(CSOM) for Remote event receivers.

public void UpdateLink(SPItemEventProperties properties)
    {
        if (properties.ListItem.Folder == null && properties.ListItem.File != null)
        {
            string linkUrl = properties.Web.Url + "/" + properties.ListItem.ParentList.Title + "/Forms/" + getContentTypeName(properties.Web, properties.ListItem.File.ParentFolder.Item.ContentTypeId) + "/docsethomepage.aspx?List=" + properties.ListItem.ParentList.ID.ToString() + "&RootFolder=" + properties.Web.Url + "/" + properties.ListItem.ParentList.Title + "/" + properties.ListItem.File.ParentFolder.Name;
            properties.ListItem["LinkName"] = linkUrl + ", " + properties.ListItem.File.ParentFolder.Item.Title;
            this.EventFiringEnabled = false;
            properties.ListItem.SystemUpdate();
            this.EventFiringEnabled = true;
        }
    }

public string getContentTypeName(SPWeb web, SPContentTypeId contentTypeID)
    {
        SPContentTypeId ct = web.AvailableContentTypes.BestMatch(contentTypeID);
        SPContentType ctt = web.AvailableContentTypes[ct];
        return ctt.Name;
    }

There are many properties which are not available in Client side object model like "properties.ListItem.File.ParentFolder.Item.ContentTypeId"

How to achieve this using CSOM?

Answer 1

I've fixed it by the following CSOM code

string fileDirRef = ""; string caseUrl = ""; string parentDocSetName = "";
List photos = clientContext.Web.Lists.GetById(guid);
ListItem item = photos.GetItemById(p);
clientContext.Load(item);
clientContext.ExecuteQuery();
clientContext.Load(clientContext.Web);
clientContext.ExecuteQuery();

if ((item.FileSystemObjectType == FileSystemObjectType.File))
            {
                fileDirRef = item["FileDirRef"].ToString();
                caseUrl = clientContext.Web.Url + "/_layouts/15/DocSetHome.aspx?id=" + fileDirRef;

                parentDocSetName = fileDirRef.Substring(fileDirRef.LastIndexOf('/') + 1);
                item["LinkName"] = caseUrl + ", " + parentDocSetName;

                item.SystemUpdate();

                clientContext.ExecuteQuery();
            }

Hope this will help someone!!