How to solve TF_E_NOLOCK：The cookie in ec is invalid

Question

I'm developing a TSF Text Services. It depend on TSF-TypeLib. Here is a part of the code of my project:

    [ComVisible(true)]
    [ClassInterface(ClassInterfaceType.None)]
    public class EditSession:BaseObject, ITfEditSession
    {
        public uint EditCookie;
        public HRESULT DoEditSession(uint ec)
        {
            EditCookie = ec;
            return S_OK();
        }
    }

    public class KeyEventSink : BaseObject, ITfKeyEventSink
    {
        private uint _clientId;
        private ITfThreadMgr _threadMgr;

        public KeyEventSink(uint clientId,ITfThreadMgr threadMgr)
        {
            _clientId = clientId;
            _threadMgr = threadMgr;
        }
        
        [DllImport("user32.dll")]
        static extern uint MapVirtualKey(uint uCode, uint uMapType);
        public HRESULT OnTestKeyDown(ITfContext pic, UIntPtr wParam, IntPtr lParam, out bool pfEaten)
        {
            var res = _threadMgr.GetFocus(out var documentMgr);
            res = documentMgr.GetTop(out var context);
            char nonVirtualKey = (char)MapVirtualKey(wParam.ToUInt32(), 2);
            Debug.WriteLine(nonVirtualKey);
            if (nonVirtualKey == 'F')
            {
                var editSession = new EditSession();
                res = context.RequestEditSession(_clientId, editSession,TF_ES.TF_ES_READWRITE, out var phrSession);
                var phrSeesionHRESULT = new HRESULT { Code = phrSession };
                if (phrSeesionHRESULT)
                {

                    var e = editSession.EditCookie;
                    res = context.GetStart(e, out var range); //A error occured 
                    Debug.WriteLine(res);
                    Debug.WriteLine((ManagerReturnValues)res.Code);
                    var charArray = "་".ToCharArray();
                    res = range.SetText(e, 0, charArray, charArray.Length);
                    pfEaten = res;
                    return res;
                }

            }
            pfEaten = false;
            return S_OK();
        }
    // Other function
    }

The error occured in the line that "res = context.GetStart(e, out var range); ".

TF_E_NOLOCK：The cookie in ec is invalid.

How to solove this problem?

Answer 1

EditSession Cookie only available in the function DoEditSession. Out the scope of this function cookie is out of date.