How to update the JSLink of a Web Part via CSOM for all subsites in Office365

I had the requirement to change the JSLink for my custom list for all the subsites of a site collection. You would normally do this via PowerShell. My customer is using Office365 (what all customers should do…) and therefore are the possibilities of PowerShell limited. I found quite some examples on how to update a JSLink of a Web Part via the UI. However I wanted to update the JSLink via code. 

I started with the project Contoso.ApplyBranding.Console from the Office App Model Samples which is btw a great starting point for working with SharePoint Apps. The example I used is a console app project which has a settings.xml file in which you can add all the sites that have to be updated.

//Loop through all sites from the settings.xml

            foreach (var site in branding.Element(“sites”).Descendants(“site”))

            {

                var siteUrl = url.TrimEnd(trimChars) + “/” + site.Attribute(“url”).Value.TrimEnd(trimChars);

                using (ClientContext clientContext = new ClientContext(siteUrl))

                {

                    //Connect to the SharePoint Online site

                    clientContext.AuthenticationMode = ClientAuthenticationMode.Default;

                    clientContext.Credentials = credentials;

                    clientContext.Load(clientContext.Web);

                    clientContext.ExecuteQuery();

 

                    //Get the list

                    List list = clientContext.Web.Lists.GetByTitle(“Listtest”);

                    clientContext.Load(list);

                    clientContext.Load(list.Forms);

                    clientContext.ExecuteQuery();

 

                    //Get all the forms

                     foreach (var spForm in list.Forms)

                     {

                         //Get the edit form

                         if (spForm.ServerRelativeUrl.Contains(“EditForm.aspx”))

                         {

                            File file = clientContext.Web.GetFileByServerRelativeUrl(spForm.ServerRelativeUrl); 

                            LimitedWebPartManager wpm = file.GetLimitedWebPartManager(PersonalizationScope.Shared); 

                            clientContext.Load(wpm.WebParts, 

                            wps => wps.Include( 

                            wp => wp.WebPart.Title)); 

                            clientContext.ExecuteQuery();

                            

                            //Set the properties for all web parts

                            foreach (WebPartDefinition wpd in wpm.WebParts) 

                            { 

                                WebPart wp = wpd.WebPart; 

                                wp.Properties[“JSLink”] = “~/sitecollection/Style Library/customer/customization.js”;

                                wpd.SaveWebPartChanges();

                                clientContext.ExecuteQuery();

                            } 

                        }

                    }

                }

            }            

 

So this is the result:

If you want you can of course also add your site collections to the settings.xml file and loop through them as well.