diff --git a/ContextMenuManager/BulePointLilac.Methods/FileExtension.cs b/ContextMenuManager/BulePointLilac.Methods/FileExtension.cs
new file mode 100644
index 0000000..6a19279
--- /dev/null
+++ b/ContextMenuManager/BulePointLilac.Methods/FileExtension.cs
@@ -0,0 +1,17 @@
+using Microsoft.Win32;
+
+namespace BulePointLilac.Methods
+{
+    public static class FileExtension
+    {
+        public const string FileExtsPath = @"HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\FileExts";
+
+        public static string GetOpenMode(string extension)
+        {
+            string mode = Registry.GetValue($@"{FileExtsPath}\{extension}\UserChoice", "ProgId", null)?.ToString();
+            if(mode != null) return mode;
+            mode = Registry.GetValue($@"HKEY_CLASSES_ROOT\{extension}", "", null)?.ToString();
+            return mode;
+        }
+    }
+}
\ No newline at end of file