How to know if RichTextBox vertical Scrollbar reached the max value?

Question

When using the richtextbox method \"ScrollToCaret\" I need to know if the scrollbar reached the top/bottom margin.

This is because when vertical scrollbar is full sc

Answer 1

This is the @King King version I've translated it to VB.NET and also added more functions, I thinkg all of them works right:

Public Class ScrollBarInfo

 _
Private Shared Function GetScrollInfo(hwnd As IntPtr, nBar As Integer, ByRef scrollInfo As SCROLLINFO) As Integer
End Function

Private Shared scrollInf As New SCROLLINFO()

Private Structure SCROLLINFO
    Public cbSize As Integer
    Public fMask As Integer
    Public min As Integer
    Public max As Integer
    Public nPage As Integer
    Public nPos As Integer
    Public nTrackPos As Integer
End Structure

Private Shared Sub Get_ScrollInfo(control As Control)
    scrollInf = New SCROLLINFO()
    scrollInf.cbSize = System.Runtime.InteropServices.Marshal.SizeOf(scrollInf)
    scrollInf.fMask = &H10 Or &H1 Or &H2
    GetScrollInfo(control.Handle, 1, scrollInf)
End Sub

Public Shared Function ReachedBottom(control As Control) As Boolean
    Get_ScrollInfo(control)
    Return scrollInf.max = scrollInf.nTrackPos + scrollInf.nPage
End Function

Public Shared Function ReachedTop(control As Control) As Boolean
    Get_ScrollInfo(control)
    Return scrollInf.nTrackPos < 0
End Function

Public Shared Function IsAtBottom(control As Control) As Boolean
    Get_ScrollInfo(control)
    Return scrollInf.max = (scrollInf.nTrackPos + scrollInf.nPage) - 1
End Function

Public Shared Function IsAtTop(control As Control) As Boolean
    Get_ScrollInfo(control)
    Return scrollInf.nTrackPos = 0
End Function

End Class