How to re-use existing/already-opened Windows Explorer window to launch Explorer

Question

I have an application that makes frequent use of launching explorer.exe. I would like to re-use existing/already-opened explorer windows instead of creating a new one each time I start the process.

Here is what my code looks like:

System.Diagnostics.ProcessStartInfo info = new System.Diagnostics.ProcessStartInfo
{
    UseShellExecute = true,
    FileName = "Explorer.exe",
    Arguments = myDirectoryPath
};
System.Diagnostics.Process.Start(info);

I didn't see a command-line switch to do this. One approach I tried was to simply kill any 1 existing explorer process and replace it with a new one:

var processes = System.Diagnostics.Process.GetProcesses(Environment.MachineName);int kills = 0;
for (int i = 0; i < processes.Length; i++)
{
    System.Diagnostics.Process p = processes[i];
    if (p.ProcessName == "explorer" && kills < 1)
        ++kills
    p.Kill();
}

But this results in the unwanted effect of not just killing 1 process, but killing explorer completely so that even the taskbar disappears.

So, how do you use an existing Explorer window, if one exists, to start Explorer?

Answer 1

The IShellWindows COM interface will give you a list of open explorer windows, you can get and set the address of any explorer window, see this blog entry for a C++ sample. I doubt .NET has a native implementation of this, so you probably need to PInvoke