Handle zips with Windoze directory separators (\) rather than the standard linux (/)

Author: MarkBaker

src/PhpSpreadsheet/Reader/Xlsx.php

@@ -403,12 +403,18 @@ private function getFromZipArchive(ZipArchive $archive, $fileName = '')
         // Sadly, some 3rd party xlsx generators don't use consistent case for filenaming
         //    so we need to load case-insensitively from the zip file
 
-        // Apache POI fixes
         $contents = $archive->getFromName($fileName, 0, ZipArchive::FL_NOCASE);
+
+        // Apache POI fixes
         if ($contents === false) {
             $contents = $archive->getFromName(substr($fileName, 1), 0, ZipArchive::FL_NOCASE);
         }
 
+        // Has the file been saved with Windoze directory separators rather than unix?
+        if ($contents === false) {
+            $contents = $archive->getFromName(str_replace('/', '\\', $fileName), 0, ZipArchive::FL_NOCASE);
+        }
+
         return ($contents === false) ? '' : $contents;
     }
 

src/PhpSpreadsheet/Shared/File.php

@@ -156,7 +156,11 @@ public static function assertFile(string $filename, string $zipMember = ''): voi
         if ($zipMember !== '') {
             $zipfile = "zip://$filename#$zipMember";
             if (!self::fileExists($zipfile)) {
-                throw new ReaderException("Could not find zip member $zipfile");
+                // Has the file been saved with Windoze directory separators rather than unix?
+                $zipfile = "zip://$filename#" . str_replace('/', '\\', $zipMember);
+                if (!self::fileExists($zipfile)) {
+                    throw new ReaderException("Could not find zip member $zipfile");
+                }
             }
         }
     }