visual studio drag form code example

Example 1: drag form in C# winform

[DllImport("user32")]
private static extern bool ReleaseCapture();

[DllImport("user32")]
private static extern int SendMessage(IntPtr hWnd, int Msg, int wp, int lp);

protected override void OnMouseDown(MouseEventArgs e)
{
  	base.OnMouseDown(e);
	if (e.Button == MouseButtons.Left)
    {
    	ReleaseCapture();
      	SendMessage(Handle, 161, 2, 0);
    }
}

Example 2: vb.net drag window without titlebar

Public Const WM_NCLBUTTONDOWN As Integer = &HA1 
Public Const HT_CAPTION As Integer = &H2 

<DllImportAttribute("user32.dll")> _ 
Public Shared Function SendMessage(ByVal hWnd As IntPtr, ByVal Msg As Integer, ByVal wParam As Integer, ByVal lParam As Integer) As Integer
End Function

<DllImportAttribute("user32.dll")> _ 
Public Shared Function ReleaseCapture() As Boolean
End Function

Private Sub Form1_MouseDown(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles Me.MouseDown, Panel1.MouseDown 
    If e.Button = Windows.Forms.MouseButtons.Left Then
        ReleaseCapture() 
        SendMessage(Handle, WM_NCLBUTTONDOWN, HT_CAPTION, 0) 
    End If
End Sub