C# Signature:
/// <summary>
/// The MoveWindow function changes the position and dimensions of the specified window. For a top-level window, the position and dimensions are relative to the upper-left corner of the screen. For a child window, they are relative to the upper-left corner of the parent window's client area.
/// </summary>
/// <param name="hWnd">Handle to the window.</param>
/// <param name="X">Specifies the new position of the left side of the window.</param>
/// <param name="Y">Specifies the new position of the top of the window.</param>
/// <param name="nWidth">Specifies the new width of the window.</param>
/// <param name="nHeight">Specifies the new height of the window.</param>
/// <param name="bRepaint">Specifies whether the window is to be repainted. If this parameter is TRUE, the window receives a message. If the parameter is FALSE, no repainting of any kind occurs. This applies to the client area, the nonclient area (including the title bar and scroll bars), and any part of the parent window uncovered as a result of moving a child window.</param>
/// <returns>If the function succeeds, the return value is nonzero.
/// <para>If the function fails, the return value is zero. To get extended error information, call GetLastError.</para></returns>
[DllImport("user32.dll", SetLastError = true)]
internal static extern bool MoveWindow(IntPtr hWnd, int X, int Y, int nWidth, int nHeight, bool bRepaint);
VB.Net Signature:
''' <summary>
''' The MoveWindow function changes the position and dimensions of the specified window. For a top-level window, the position and dimensions are relative to the upper-left corner of the screen. For a child window, they are relative to the upper-left corner of the parent window's client area.
''' </summary>
''' <param name="hWnd">Handle to the window.</param>
''' <param name="X">Specifies the new position of the left side of the window.</param>
''' <param name="Y">Specifies the new position of the top of the window.</param>
''' <param name="nWidth">Specifies the new width of the window.</param>
''' <param name="nHeight">Specifies the new height of the window.</param>
''' <param name="bRepaint">Specifies whether the window is to be repainted. If this parameter is TRUE, the window receives a message. If the parameter is FALSE, no repainting of any kind occurs. This applies to the client area, the nonclient area (including the title bar and scroll bars), and any part of the parent window uncovered as a result of moving a child window.</param>
''' <returns>If the function succeeds, the return value is nonzero.
''' <para>If the function fails, the return value is zero. To get extended error information, call GetLastError.</para></returns>
<DllImport("user32.dll")> _
Public Shared Function MoveWindow(ByVal hWnd As IntPtr, ByVal x As Integer, ByVal y As Integer, ByVal nWidth As Integer, ByVal nHeight As Integer, ByVal bRepaint As Boolean) As Boolean
End Function
C++ Signature:
[DllImport("User32.dll")]
extern bool MoveWindow(IntPtr handle, int x, int y, int width, int height, bool redraw);
User-Defined Types:
None.
Notes:
Note 1
Note that when performing arithmetic operations in vb.net (3.0) to resize a window (For example, calculating the height and width on the basis of two int32's) you should covert the resulting variable to an uint32 (unsigned integer) before passing it to the DLL. The below code is a badly coded example of this. The RECT used in this code is the size of second window. The first two examples behave as expected, but the latter example resizes the window to minimal size.
WORKS
- MoveWindow(hwnd, (RECT.left RECT.right) / 2, (RECT.top RECT.bottom) / 2, UInt32.Parse(RECT.right - RECT.left), UInt32.Parse(RECT.bottom - RECT.top), True)
- MoveWindow(hwnd, (RECT.left RECT.right) / 2, (RECT.top RECT.bottom) / 2, 609, 195, True)
FAILS
- MoveWindow(hwnd, (RECT.left RECT.right) / 2, (RECT.top RECT.bottom) / 2,(RECT.right - RECT.left), (RECT.bottom - RECT.top), True)
Note 2
The api can resize windows that are normally not re sizable, including the ones build in windows such as Calc.exe and Osk.exe. Note that sizes are saved on application exit, so if don't accidentally resize them to dimensions where they become unusable as you will not be able to recover their normal size trough the applications normal interface!
Tips & Tricks:
None.
Sample Code:
C# Code:
class Program
{
internal struct RECT
{
public int left;
public int top;
public int right;
public int bottom;
}
[DllImport("user32.dll", ExactSpelling = true, SetLastError = true)]
internal static extern IntPtr GetForegroundWindow();
[DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall, ExactSpelling = true, SetLastError = true)]
internal static extern bool GetWindowRect(IntPtr hWnd, ref RECT rect);
[DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall, ExactSpelling = true, SetLastError = true)]
internal static extern void MoveWindow(IntPtr hwnd, int X, int Y, int nWidth, int nHeight, bool bRepaint);
static void Main(string[] args)
{
IntPtr id;
RECT Rect = new RECT();
Thread.Sleep(2000);
id = GetForegroundWindow();
Random myRandom = new Random();
GetWindowRect(id, ref Rect);
MoveWindow(id, myRandom.Next(1024), myRandom.Next(768), Rect.right - Rect.left, Rect.bottom - Rect.top, true);
}
}
VB code:
Public Declare Auto Function MoveWindow Lib "user32.dll" ( _
ByVal hWnd As IntPtr, _
ByVal X As Int32, _
ByVal Y As Int32, _
ByVal nWidth As Int32, _
ByVal nHeight As Int32, _
ByVal bRepaint As Boolean _
) As Boolean
Private Sub ResizeMe_MouseMove(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles ResizeMe.MouseMove
If e.Button = MouseButtons.Left Then
MoveWindow(Me.Handle, Me.Location.X, Me.Location.Y, (Control.MousePosition.X - (Me.Left)) + 10, (Control.MousePosition.Y - Me.Top) + 10, True)
Me.Refresh()
System.Windows.Forms.Application.DoEvents()
End If
contributed by http://kaleemsoft.com
Alternative Managed API:
Omnicoder's Managed Windows API: http://www.fileden.com/files/2008/4/5/1852663/ManWinAPI.zip
Additional Uses (Contributed by Hayden B):
I always enjoyed how when you typed an incorrect password on a mac the window shakes itself back and forth like it's saying no. Here's a simple piece of code you could use in a login form to do just that.
VB code:
Public Declare Auto Function MoveWindow Lib "user32.dll" ( _
ByVal hWnd As IntPtr, _
ByVal X As Int32, _
ByVal Y As Int32, _
ByVal nWidth As Int32, _
ByVal nHeight As Int32, _
ByVal bRepaint As Boolean _
) As Boolean
Private InitX As Integer
Private LR As String = "L"
Private C As Integer = 0
Private X As Integer = 0
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
InitX = Me.Location.X
X = InitX
C = 0
Timer1.Interval = 1
Timer1.Start()
End Sub
Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick
C += 1
If X = InitX - 6 Then
LR = "R"
ElseIf X = InitX + 6 Then
LR = "L"
End If
If LR = "L" Then
X -= 2
Else
X += 2
End If
MoveWindow(Me.Handle, X, Me.Location.Y, Me.Width, Me.Height, True)
Me.Refresh()
System.Windows.Forms.Application.DoEvents()
If C = 30 Then
Timer1.Stop()
End If
End Sub
