private static extern IntPtr GetCurrentThread();

    uint appThread = GetCurrentThreadId();

AppDomain.GetCurrentThreadId is marked as deprecated in favour of Thread.ManagedThreadId but this will not to work with unmanaged API.

You can use the GetCurrentThreadId API as well:

     SetWindowsHookEx(HookType.WH_KEYBOARD, this.myCallbackDelegate, IntPtr.Zero, AppDomain.GetCurrentThreadId());

    SetWindowsHookEx(HookType.WH_KEYBOARD, Me.myCallbackDelegate, IntPtr.Zero, AppDomain.GetCurrentThreadId())

    private static extern IntPtr GetCurrentThread();

    if (!OpenThreadToken(GetCurrentThread(), TOKEN_READ | TOKEN_IMPERSONATE, true, out hToken))

static extern uint GetCurrentThreadId();

    info.ThreadId = GetCurrentThreadId();

static extern void GetCurrentThreadStackLimits(out uint lowLimit, out uint highLimit);

Declare Function GetCurrentThreadStackLimits Lib "kernel32.dll" (ByRef lowLimit As UInteger, ByRef highLimit As UInteger)

GetCurrentThreadStackLimits(out low, out high);

static extern uint GetCurrentThreadId();

Public Shared Function GetCurrentThreadId() As UInteger

  System.AppDomain.GetCurrentThreadId() (This is deprecated in .NET 2.0)

     threadId = (uint)AppDomain.GetCurrentThreadId();

    if ( !GetThreadContext( GetCurrentThread(), ref cntx ) )

    if ( !GetThreadSelectorEntry( GetCurrentThread(), cntx.SegDs, out ldt ) )

GetThreadTimes(GetCurrentThread(),out l,out l,out KernelStart,out UserStart);

    GetThreadTimes(GetCurrentThread(),out l,out l,out KernelEnd,out UserEnd);