How to get localized field titles via CSOM in Sharepoint

Some time ago I wrote article which shows how to localize web part titles via CSOM. If you are not familiar with it I recommend to read it before continue as it has useful information about Sharepoint MUI feature in general: Localize web part titles via client object model in Sharepoint. In current post I will show how to get localized field titles via CSOM in Sharepoint. This technique can be used both in on-prem and online versions.

Currently CSOM has Field.TitleResource property and it looks suitable when you want to get localized title of some field. However this is not the case. In order to get localized fields’ titles you still have to use Field.Title property but with little tuning of ClientContext – similar to those which is mentioned in the article above. More specifically you need to specify target language via “Accept-Language” HTTP header associated with ClientContext and then request field titles (of course assuming that fields have these localized titles provisioned. See e.g. Provision multilingual sites with PnP templates to see how to provision multilingual fields’ titles using PnP templates). Here is the code which shows this concept:

string siteUrl = "...";
string clientId = "...";
string clientSecret = "...";
int lcid = ...;
using (var ctx = new OfficeDevPnP.Core.AuthenticationManager().GetAppOnlyAuthenticatedContext(siteUrl, clientId, clientSecret))
{
 ctx.PendingRequest.RequestExecutor.WebRequest.Headers["Accept-Language"] = new CultureInfo(lcid).Name;
 ctx.Load(ctx.Web);
 ctx.Load(ctx.Web.Fields, f => f.Include(c => c.Id, c => c.Title));
 ctx.ExecuteQueryRetry();
 ...
}

As result when you will iterate through site columns retrieved this way they will contain titles localized for language specified with lcid parameter.