尝试这样做，您可以在将进程ID打印到文本框之前，在do while循环中指定它。

public partial class Form1 : Form
{
    private readonly IntPtr _bufferReadyEvent;
    private readonly IntPtr _dataReadyEvent;
    private readonly IntPtr _mapping;
    private readonly IntPtr _file;
    private const int WaitTimeout = 500;
    private const uint WAIT_OBJECT_0 = 0;
    private readonly Thread _reader;

    [DllImport("kernel32.dll", SetLastError = true)]
    private static extern bool SetEvent(IntPtr hEvent);

    [DllImport("kernel32.dll", SetLastError = true, CharSet = CharSet.Auto)]
    private static extern IntPtr CreateFileMapping(IntPtr hFile, IntPtr lpFileMappingAttributes, FileMapProtection flProtect, uint dwMaximumSizeHigh, uint dwMaximumSizeLow, string lpName);

    [DllImport("kernel32.dll", SetLastError = true)]
    private static extern IntPtr CreateEvent(IntPtr lpEventAttributes, bool bManualReset, bool bInitialState, string lpName);

    [DllImport("kernel32.dll", SetLastError = true)]
    private static extern uint WaitForSingleObject(IntPtr handle, uint milliseconds);

    [DllImport("kernel32.dll", SetLastError = true)]
    private static extern IntPtr MapViewOfFile(IntPtr hFileMappingObject, FileMapAccess dwDesiredAccess, uint dwFileOffsetHigh, uint dwFileOffsetLow, uint dwNumberOfBytesToMap);

    [Flags]
    private enum FileMapAccess
    {
        FileMapRead = 0x0004,
    }

    [Flags]
    private enum FileMapProtection
    {
        PageReadWrite = 0x04,
    }

    public Form1()
    {
        InitializeComponent();

        _bufferReadyEvent = CreateEvent(IntPtr.Zero, false, false, "DBWIN_BUFFER_READY");
        if (_bufferReadyEvent == IntPtr.Zero)
            Marshal.ThrowExceptionForHR(Marshal.GetLastWin32Error());

        _dataReadyEvent = CreateEvent(IntPtr.Zero, false, false, "DBWIN_DATA_READY");
        if (_dataReadyEvent == IntPtr.Zero)
            Marshal.ThrowExceptionForHR(Marshal.GetLastWin32Error());

        _mapping = CreateFileMapping(new IntPtr(-1), IntPtr.Zero, FileMapProtection.PageReadWrite, 0, 4096, "DBWIN_BUFFER");
        if (_mapping == IntPtr.Zero)
            Marshal.ThrowExceptionForHR(Marshal.GetLastWin32Error());

        _file = MapViewOfFile(_mapping, FileMapAccess.FileMapRead, 0, 0, 1024);
        if (_file == IntPtr.Zero)
            Marshal.ThrowExceptionForHR(Marshal.GetLastWin32Error());

        _reader = new Thread(Read)
        {
            IsBackground = true
        };
        _reader.Start();
    }

    private void Read()
    {
        try
        {
            do
            {
                SetEvent(_bufferReadyEvent);

                uint wait = WaitForSingleObject(_dataReadyEvent, WaitTimeout);
                if (wait == WAIT_OBJECT_0) // we don't care about other return values
                {
                    int pid = Marshal.ReadInt32(_file);
                    string text = Marshal.PtrToStringAnsi(new IntPtr(_file.ToInt32() + Marshal.SizeOf(typeof(int)))).TrimEnd(null);
                    if (string.IsNullOrEmpty(text))
                    {
                        continue;
                    }
                    Textbox_DebugConsole.Invoke((MethodInvoker)delegate
                    {
                        Textbox_DebugConsole.AppendText(string.Format("{0} - {1}", pid, text + Environment.NewLine));
                    });
                }
            }
            while (true);
        }
        catch (Exception e)
        {
            MessageBox.Show(e.Message, Application.ProductName, MessageBoxButtons.OK, MessageBoxIcon.Error);
        }
    }
}