I am currently using REST to query a discussion board list. The results I am then displaying nicely in a table using bootstrap.
We are using office 365. The REST query returns an authorID. How can we use csom to get the username from the authorID returned from the REST query.
In fact, there is no need to perform an additional request to retrieve User details by its Id.
Since you are using SharePoint REST API, the following single query returns Discussion List data including Author details (Id, Title) using the projection for an Author column:
/_api/web/lists/getbytitle('Discussions List')/items?$select=Title,Author/ID,Author/Title&$expand=Author/ID,Author/Title
Please follow Getting User Information with the SharePoint 2013 REST API post for a more details.
You can use CSOM but also the REST API to get all your information.
<app web url>/_api/web/GetUserBy(<userid>)
or
<app web url>/_api/SP.AppContextSite(@target)/web/getuserbyid(<userid>)?@target='<host web url>'
For more information see MSDN documentation
You can try following code:
var targetSite = new Uri("site");
var login = "username";
var password = "password";
var securePassword = new SecureString();
foreach (char c in password)
{
securePassword.AppendChar(c);
}
var onlineCredentials = new SharePointOnlineCredentials(login, securePassword);
using (ClientContext clientContext = new ClientContext(targetSite))
{
clientContext.Credentials = onlineCredentials;
Web web = clientContext.Web;
Microsoft.SharePoint.Client.ListItem userInfo = web.SiteUserInfoList.GetItemById(lookupid);
clientContext.Load(userInfo);
clientContext.ExecuteQuery();
Useremail = userInfo["EMail"].ToString();
UserName = userInfo["Title"].ToString();
}
