I'm trying to find the first visible instance of Word. I have found some helpful code here and modified it sligthly.
using System;
using System.Diagnostics;
using System.Runtime.InteropServices;
using System.Runtime.InteropServices.ComTypes;
using Microsoft.Office.Interop.Word;
namespace TestConsole
{
internal class Program
{
[DllImport("ole32.dll")]
private static extern int GetRunningObjectTable(uint reserved, out IRunningObjectTable pprot);
private static void Main(string[] args)
{
Application word1 = new Application();
word1.Visible = false;
Application word2 = new Application();
word2.Visible = true;
Application word3 = new Application();
word3.Visible = false;
int index = 0;
while (true)
{
Application application = Program.GetRunningCOMObjectOfType<Application>(++index);
if (application != null)
{
Console.WriteLine($"{index}) IsVisible: {application.Visible}");
Debug.WriteLine($"{index}) IsVisible: {application.Visible}");
}
else
{
break;
}
}
Console.WriteLine("############# End of program #############");
Console.ReadLine();
}
public static T GetRunningCOMObjectOfType<T>(int index)
{
IRunningObjectTable runningObjectTable = null;
IEnumMoniker monikerList = null;
try
{
if (GetRunningObjectTable(0, out runningObjectTable) != 0 || runningObjectTable == null)
{
return default(T);
}
runningObjectTable.EnumRunning(out monikerList);
monikerList.Reset();
IMoniker[] monikerContainer = new IMoniker[1];
IntPtr pointerFetchedMonikers = IntPtr.Zero;
int counter = 0;
while (monikerList.Next(1, monikerContainer, pointerFetchedMonikers) == 0)
{
runningObjectTable.GetObject(monikerContainer[0], out object comInstance);
if (comInstance is T castedInstance)
{
if (index == ++counter)
{
return castedInstance;
}
}
}
}
finally
{
if (runningObjectTable != null)
{
Marshal.ReleaseComObject(runningObjectTable);
}
if (monikerList != null)
{
Marshal.ReleaseComObject(monikerList);
}
}
return default(T);
}
}
}
The result of this code looks like this:
1) IsVisible: False
2) IsVisible: False
3) IsVisible: False
I expect that for one instance Visible should return true. It seems that always the first instance is returned. If word1 is made visible true is returned for all instances.