Question

my question is as is:How to detect if a scrollbar is at or not at the end of a richtextbox?

edit: when I say at the end I mean completely scrolled to the bottom, not anywhere else.

Answer 1

Check out the GetScrollRange and GetScrollPos API…

Private Const SBS_HORZ = 0 Private Const SBS_VERT = 1  <DllImport('user32.dll')> _ Public Function GetScrollRange(ByVal hWnd As IntPtr, ByVal nBar As Integer, _                                ByRef lpMinPos As Integer, _                                ByRef lpMaxPos As Integer) As Boolean End Function  <DllImport('user32.dll')> _ Public Function GetScrollPos(ByVal hWnd As Integer, _                              ByVal nBar As Integer) As Integer End Function  // ...  Dim scrollMin as Integer = 0 Dim scrollMax as Integer = 0  If(GetScrollRange(rtb.Handle, SBS_VERT, scrollMin, scrollMax) Then    Dim pos as Integer = GetScrollPos(rtb.Handle, SBS_VERT)     // Detect if they're at the bottom EndIf 

Notes:

To determine if the scrollbar is visible, call GetWindowLong and check for WS_VSCROLL

To determine the max value the slider can get to, call GetScrollInfo; I think the maximum value is

scrollMax - largeChange + 1