Enable Non-Client Area DPI scaling in WinForms

MainForm.cs

// app.manifest which declares this application Monitor DPI aware is required.
using System;
using System.Diagnostics;
using System.Runtime.InteropServices;
using System.Windows.Forms;

public partial class MainForm : Form
{
    public MainForm()
    {
        InitializeComponent();
    }

    [DllImport("User32.dll", SetLastError = true)]
    private static extern bool EnableNonClientDpiScaling(IntPtr hwnd);

    private const int WM_NCCREATE = 0x0081;
    private const int WM_DPICHANGED = 0x02E0;

    protected override void WndProc(ref Message m)
    {
        switch (m.Msg)
        {
            case WM_NCCREATE:
                var result = EnableNonClientDpiScaling(this.Handle);
                Debug.WriteLine($"{nameof(EnableNonClientDpiScaling)} -> {result}");
                break;

            case WM_DPICHANGED:
                Debug.WriteLine($"DPI Changed!");
                break;
        }
        base.WndProc(ref m);
    }
}