support for .NET framework 3.5

Still have bugs

Net35/HandyControl_Net35/Shell/Standard/DpiHelper.cs

@@ -0,0 +1,64 @@
+namespace Standard
+{
+    using System;
+    using System.Diagnostics.CodeAnalysis;
+    using System.Windows;
+    using System.Windows.Media;
+
+    internal static class DpiHelper
+    {
+        private static Matrix _transformToDevice;
+        private static Matrix _transformToDip;
+
+        [SuppressMessage("Microsoft.Performance", "CA1810:InitializeReferenceTypeStaticFieldsInline")]
+        static DpiHelper()
+        {
+            using (Standard.SafeDC edc = Standard.SafeDC.GetDesktop())
+            {
+                int deviceCaps = Standard.NativeMethods.GetDeviceCaps(edc, Standard.DeviceCap.LOGPIXELSX);
+                int num2 = Standard.NativeMethods.GetDeviceCaps(edc, Standard.DeviceCap.LOGPIXELSY);
+                _transformToDip = Matrix.Identity;
+                _transformToDip.Scale(96.0 / ((double) deviceCaps), 96.0 / ((double) num2));
+                _transformToDevice = Matrix.Identity;
+                _transformToDevice.Scale(((double) deviceCaps) / 96.0, ((double) num2) / 96.0);
+            }
+        }
+
+        public static Point DevicePixelsToLogical(Point devicePoint)
+        {
+            return _transformToDip.Transform(devicePoint);
+        }
+
+        public static Rect DeviceRectToLogical(Rect deviceRectangle)
+        {
+            Point point = DevicePixelsToLogical(new Point(deviceRectangle.Left, deviceRectangle.Top));
+            return new Rect(point, DevicePixelsToLogical(new Point(deviceRectangle.Right, deviceRectangle.Bottom)));
+        }
+
+        public static Size DeviceSizeToLogical(Size deviceSize)
+        {
+            Point point = DevicePixelsToLogical(new Point(deviceSize.Width, deviceSize.Height));
+            return new Size(point.X, point.Y);
+        }
+
+        public static Point LogicalPixelsToDevice(Point logicalPoint)
+        {
+            return _transformToDevice.Transform(logicalPoint);
+        }
+
+        [SuppressMessage("Microsoft.Performance", "CA1811:AvoidUncalledPrivateCode")]
+        public static Rect LogicalRectToDevice(Rect logicalRectangle)
+        {
+            Point point = LogicalPixelsToDevice(new Point(logicalRectangle.Left, logicalRectangle.Top));
+            return new Rect(point, LogicalPixelsToDevice(new Point(logicalRectangle.Right, logicalRectangle.Bottom)));
+        }
+
+        [SuppressMessage("Microsoft.Performance", "CA1811:AvoidUncalledPrivateCode")]
+        public static Size LogicalSizeToDevice(Size logicalSize)
+        {
+            Point point = LogicalPixelsToDevice(new Point(logicalSize.Width, logicalSize.Height));
+            return new Size { Width = point.X, Height = point.Y };
+        }
+    }
+}
+