NativeMethods.vb

' Licensed to the .NET Foundation under one or more agreements.
' The .NET Foundation licenses this file to you under the MIT license.
' See the LICENSE file in the project root for more information.

Imports System.Runtime.InteropServices

Namespace Microsoft.VisualBasic.CompilerServices

    <ComVisible(False)>
    Friend Module NativeMethods

        <DllImport("user32.dll")>
        Public Function LockWindowUpdate(hWndLock As IntPtr) As Boolean
        End Function

#Region "Scroll Bar Support"

        Public Enum SBOrientation As Integer
            HORZ = &H0
            VERT = &H1
            CTL = &H2
            BOTH = &H3
        End Enum

        <Flags>
        Public Enum ScrollInfoMasks As Integer
            RANGE = &H1
            PAGE = &H2
            POS = &H4
            DISABLENOSCROLL = &H8
            TRACKPOS = &H10
            ALL = RANGE Or PAGE Or POS Or TRACKPOS
        End Enum

        <DllImport("user32.dll", EntryPoint:=NameOf(GetScrollBarInfo))>
        Friend Function GetScrollBarInfo(hwnd As IntPtr,
                                         idObject As Integer,
                                         ByRef psbi As SCROLLBARINFO
                                         ) As <MarshalAs(UnmanagedType.Bool)> Boolean
        End Function

        <DllImport("user32.dll", SetLastError:=True)>
        Friend Function GetScrollInfo(
                                     hWnd As IntPtr,
                                     <MarshalAs(UnmanagedType.I4)> fnBar As SBOrientation,
                                     ByRef lpsi As SCROLLINFO
                                     ) As Integer
        End Function

        <DllImport("user32.dll", SetLastError:=True, ThrowOnUnmappableChar:=True, CharSet:=CharSet.Auto)>
        Friend Function SetScrollInfo(
                                     hWnd As IntPtr,
                                     <MarshalAs(UnmanagedType.I4)> nBar As SBOrientation,
                                     <MarshalAs(UnmanagedType.Struct)> ByRef lpsi As SCROLLINFO,
                                     <MarshalAs(UnmanagedType.Bool)> bRepaint As Boolean
                                     ) As Integer
        End Function

        'This function queries or sets system-wide parameters, and updates the user profile during the process.
        <DllImport("user32", EntryPoint:=NameOf(SystemParametersInfo), CharSet:=CharSet.Unicode, SetLastError:=True)>
        Public Function SystemParametersInfo(intAction As Integer,
                                             intParam As Integer,
                                             strParam As String,
                                             intWinIniFlag As Integer
                                            ) As Integer
            ' returns non-zero value if function succeeds
        End Function

        <StructLayout(LayoutKind.Sequential)>
        Friend Structure RECT
            Public Left, Top, Right, Bottom As Integer

            Public Function ToRectangle() As Rectangle
                Return New Rectangle(Left, Top, Right - Left, Bottom - Top)
            End Function

        End Structure

        <Serializable, StructLayout(LayoutKind.Sequential)>
        Friend Structure SCROLLINFO
            Public CB_Size As UInteger
            <MarshalAs(UnmanagedType.U4)> Public F_Mask As ScrollInfoMasks
            Public N_Min As Integer
            Public N_Max As Integer
            Public N_Page As UInteger
            Public N_Pos As Integer
            Public N_TrackPos As Integer
        End Structure

        <StructLayout(LayoutKind.Sequential)>
        Public Structure SCROLLBARINFO
            Public CB_Size As Integer
            Public RC_ScrollBar As RECT
            Public DXY_LineButton As Integer
            Public XY_ThumbTop As Integer
            Public XY_ThumbBottom As Integer
            Public Reserved As Integer

            <MarshalAs(UnmanagedType.ByValArray, SizeConst:=6, ArraySubType:=UnmanagedType.U4)>
            Public RgState() As Integer

        End Structure

#End Region

    End Module

End Namespace