This is a follow up question to one of the answers provided for post Quit() causes Access to become visible for a moment.
The answer recommends that I move the window off screen so that the flickering window can't be seen.
If I understand the accepted answer for the question C# Process.MainWindowHandle always returns IntPtr Zero
An application that has changed its visibility (accApp.Visible = false;
) does not have/return/initialize/... an IntPtr and it will always be set to zero.
How can I move this window/app off screen so that users will never see it. I don't want to make it visible and then have my program pop/move it off screen after. Unless there is a way to prevent the visibility to extend to the users eyes (Don't want to see the window ever).
In theory could I somehow pause screen rendering, make it visible, move it and then resume screen rendering? (doubtful this is a good solution)
Since my previous post I have moved the code creating the application into its separate class to allow for only one instance of the application to run instead of the previous way which was generating a new application for each request.
public class ConnectionManager
{
[DllImport("user32.dll")]
static extern int GetWindowThreadProcessId(int hWnd, out int lpdwProcessId);
//Old Code for tying to resolve flashing access window.
//[DllImport("user32.dll", EntryPoint = "SetWindowPos")]
//public static extern IntPtr SetWindowPos(IntPtr hWnd, int hWndInsertAfter, int x, int Y, int cx, int cy, int wFlags);
public ConnectionManager()
{
Console.WriteLine("Connection Manager Started");
AppDomain.CurrentDomain.ProcessExit += new EventHandler(OnProcessExit);
}
void OnProcessExit(object sender, EventArgs e)
{
BreakAllConnections();
}
private Microsoft.Office.Interop.Excel.Application _excelApp;
public Microsoft.Office.Interop.Excel.Application excelApp
{
get
{
if (_excelApp == null)
{
try
{
_excelApp = new Microsoft.Office.Interop.Excel.Application();
}
catch
{
//TODO Add Termination
MessageBox.Show("Abort Error: Could not open Exel Application");
}
}
return _excelApp;
}
}
private Microsoft.Office.Interop.Access.Application _accessApp;
public Microsoft.Office.Interop.Access.Application accessApp
{
get
{
if (_accessApp == null)
{
try
{
_accessApp = new Microsoft.Office.Interop.Access.Application();
//Old Code for tying to resolve flashing access window.
//GetWindowThreadProcessId(_accessApp.hWndAccessApp(), out int id);
//IntPtr handle = Process.GetProcessById(id).MainWindowHandle;
//if (handle != IntPtr.Zero)
//{
// const short SWP_NOSIZE = 1;
// const short SWP_NOZORDER = 0X4;
// SetWindowPos(handle, 0, 10000, 10000, 0, 0, SWP_NOZORDER | SWP_NOSIZE | 0);
//}
}
catch
{
//TODO Add Termination
MessageBox.Show("Abort Error: Could not open Exel Application");
}
}
return _accessApp;
}
}
public void BreakAllConnections()
{
try
{
if (_excelApp != null) { _excelApp.Quit(); Marshal.ReleaseComObject(_excelApp); }
}
catch
{
GetWindowThreadProcessId(_excelApp.Hwnd, out int id);
Process.GetProcessById(id).Kill();
}
try
{
if (_accessApp != null) { _accessApp.Quit(); Marshal.ReleaseComObject(_accessApp); }
}
catch
{
GetWindowThreadProcessId(_accessApp.hWndAccessApp(), out int id);
Process.GetProcessById(id).Kill();
}
}
}