From 7d8c00c9b9678f26ee8ae2932378d81108a7ac7d Mon Sep 17 00:00:00 2001
From: halinhtvn3a <77691576+halinhtvn3a@users.noreply.github.com>
Date: Fri, 27 Mar 2026 00:48:05 +0700
Subject: [PATCH] refactor: file streams not properly disposed on preview
 failure

The `PreviewFile` method opens a file stream with `File.Open()` but doesn't handle exceptions.
If an exception occurs after opening the stream but before assignment to the `Document` property,
the stream will leak. This is a resource leak that could cause file locking issues or
exhaust file handles over time, especially when previewing problematic files.


Affected files: RichTextViewer.xaml.cs

Signed-off-by: halinhtvn3a <77691576+halinhtvn3a@users.noreply.github.com>
---
 .../RichTextViewer.xaml.cs                           | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/FileExplorer.Extension.RichTextPreview/RichTextViewer.xaml.cs b/FileExplorer.Extension.RichTextPreview/RichTextViewer.xaml.cs
index 34835e2..8105407 100644
--- a/FileExplorer.Extension.RichTextPreview/RichTextViewer.xaml.cs
+++ b/FileExplorer.Extension.RichTextPreview/RichTextViewer.xaml.cs
@@ -36,7 +36,17 @@ public RichTextViewer()
         public Task PreviewFile(string filePath)
         {
             ZoomFactor = 100f;
-            Document = File.Open(filePath, FileMode.Open, FileAccess.Read, FileShare.ReadWrite | FileShare.Delete);
+            Stream stream = null;
+            try
+            {
+                stream = File.Open(filePath, FileMode.Open, FileAccess.Read, FileShare.ReadWrite | FileShare.Delete);
+                Document = stream;
+            }
+            catch
+            {
+                stream?.Dispose();
+                throw;
+            }
 
             return Task.CompletedTask;
         }