From 2590ea5bdbaef568b79c87a4d4ad65e97a9198da Mon Sep 17 00:00:00 2001
From: CJK_mkp <113243675+CJKmkp@users.noreply.github.com>
Date: Mon, 23 Mar 2026 16:46:28 +0800
Subject: [PATCH] Fix PPT disconnect null check crash (#413)

---
 Ink Canvas/Helpers/ROTPPTManager.cs | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/Ink Canvas/Helpers/ROTPPTManager.cs b/Ink Canvas/Helpers/ROTPPTManager.cs
index 333de9b2..4044058a 100644
--- a/Ink Canvas/Helpers/ROTPPTManager.cs	
+++ b/Ink Canvas/Helpers/ROTPPTManager.cs	
@@ -1344,10 +1344,22 @@ namespace Ink_Canvas.Helpers
             catch { }
         }
 
+        private static bool IsObjectNull(object comObject)
+        {
+            return ReferenceEquals(comObject, null);
+        }
+
         private void DisconnectFromPPT()
         {
-            if (PPTApplication == null && _pptActivePresentation == null && _pptSlideShowWindow == null &&
-                CurrentPresentation == null && CurrentSlides == null && CurrentSlide == null)
+            object pptApplication = PPTApplication;
+            object activePresentation = _pptActivePresentation;
+            object slideShowWindow = _pptSlideShowWindow;
+            object currentPresentation = CurrentPresentation;
+            object currentSlides = CurrentSlides;
+            object currentSlide = CurrentSlide;
+
+            if (IsObjectNull(pptApplication) && IsObjectNull(activePresentation) && IsObjectNull(slideShowWindow) &&
+                IsObjectNull(currentPresentation) && IsObjectNull(currentSlides) && IsObjectNull(currentSlide))
             {
                 return;
             }