月更

AntDesignWPF/Extensions/UiElementExtensions.cs

@@ -0,0 +1,37 @@
+
+using System.Windows;
+
+namespace AntDesignWPF.Extensions;
+
+internal static class UiElementExtensions
+{
+    private static int Get_X_LParam(IntPtr lParam) { return (short)(lParam.ToInt32() & 0xFFFF); }
+
+    private static int Get_Y_LParam(IntPtr lParam) { return (short)(lParam.ToInt32() >> 16); }
+
+    /// <summary>
+    /// 不要在 NCHITTEST、NCLBUTTONUP、NCLBUTTONDOWN 消息之外调用它！
+    /// </summary>
+    /// <returns>如果鼠标位于元素上<see langword="true"/>。 否则，<see langword="false"/> </returns>
+    public static bool IsMouseOverElement(this UIElement element, IntPtr lParam)
+    {
+        // 此方法将非常频繁地调用，并且必须尽可能简单。
+        if (lParam == IntPtr.Zero)
+        {
+            return false;
+        }
+
+        try
+        {
+            var mousePosScreen = new Point(Get_X_LParam(lParam), Get_Y_LParam(lParam));
+            var bounds = new Rect(default, element.RenderSize);
+
+            Point mousePosRelative = element.PointFromScreen(mousePosScreen);
+
+            return bounds.Contains(mousePosRelative);
+        } catch
+        {
+            return false;
+        }
+    }
+}