我发现了一种使用WinAPI获取dpi的方法。首先需要引用System.Drawing
和System.Windows.Forms
,可以使用WinAPI从显示区域上的某个点获取监视器句柄 - Screen
类可以给我们这些点。然后GetDpiForMonitor
函数返回指定监视器的dpi。
public static class ScreenExtensions
{
public static void GetDpi(this System.Windows.Forms.Screen screen, DpiType dpiType, out uint dpiX, out uint dpiY)
{
var pnt = new System.Drawing.Point(screen.Bounds.Left + 1, screen.Bounds.Top + 1);
var mon = MonitorFromPoint(pnt, 2/*MONITOR_DEFAULTTONEAREST*/);
GetDpiForMonitor(mon, dpiType, out dpiX, out dpiY);
}
//https://msdn.microsoft.com/en-us/library/windows/desktop/dd145062(v=vs.85).aspx
[DllImport("User32.dll")]
private static extern IntPtr MonitorFromPoint([In]System.Drawing.Point pt, [In]uint dwFlags);
//https://msdn.microsoft.com/en-us/library/windows/desktop/dn280510(v=vs.85).aspx
[DllImport("Shcore.dll")]
private static extern IntPtr GetDpiForMonitor([In]IntPtr hmonitor, [In]DpiType dpiType, [Out]out uint dpiX, [Out]out uint dpiY);
}
//https://msdn.microsoft.com/en-us/library/windows/desktop/dn280511(v=vs.85).aspx
public enum DpiType
{
Effective = 0,
Angular = 1,
Raw = 2,
}
有三种缩放类型,您可以在MSDN中找到详细介绍。
我用一个新的WPF应用程序快速测试了一下:
private void Window_Loaded(object sender, System.Windows.RoutedEventArgs e)
{
var sb = new StringBuilder();
sb.Append("Angular\n");
sb.Append(string.Join("\n", Display(DpiType.Angular)));
sb.Append("\nEffective\n");
sb.Append(string.Join("\n", Display(DpiType.Effective)));
sb.Append("\nRaw\n");
sb.Append(string.Join("\n", Display(DpiType.Raw)));
this.Content = new TextBox() { Text = sb.ToString() };
}
private IEnumerable<string> Display(DpiType type)
{
foreach (var screen in System.Windows.Forms.Screen.AllScreens)
{
uint x, y;
screen.GetDpi(type, out x, out y);
yield return screen.DeviceName + " - dpiX=" + x + ", dpiY=" + y;
}
}
希望这可以帮到你!