diff --git a/src/Writer/WriterAbstract.php b/src/Writer/WriterAbstract.php
index fd7c472..a2a5e37 100644
--- a/src/Writer/WriterAbstract.php
+++ b/src/Writer/WriterAbstract.php
@@ -22,6 +22,9 @@ abstract class WriterAbstract implements WriterInterface
     /** @var resource Pointer to the file/stream we will write to */
     protected $filePointer;
 
+    /** @var bool faut-il garder ouvert le flux quand close() est appelé? */
+    protected $dontCloseFilePointer = false;
+
     /** @var bool Indicates whether the writer has been opened or not */
     protected $isWriterOpened = false;
 
@@ -57,6 +60,20 @@ abstract class WriterAbstract implements WriterInterface
         return $this;
     }
 
+    public function writeToStream($filePointer)
+    {
+      $this->outputFilePath = null;
+
+      $this->filePointer = $filePointer;
+      $this->dontCloseFilePointer = true;
+      $this->throwIfFilePointerIsNotAvailable();
+
+      $this->openWriter();
+      $this->isWriterOpened = true;
+
+      return $this;
+    }
+
     /**
      * {@inheritdoc}
      */
@@ -177,7 +194,7 @@ abstract class WriterAbstract implements WriterInterface
 
         $this->closeWriter();
 
-        if (\is_resource($this->filePointer)) {
+        if (!$this->dontCloseFilePointer && \is_resource($this->filePointer)) {
             $this->globalFunctionsHelper->fclose($this->filePointer);
         }
 
diff --git a/src/Reader/XLSX/Helper/CellValueFormatter.php b/src/Reader/XLSX/Helper/CellValueFormatter.php
index 1734fb5..08e5282 100644
--- a/src/Reader/XLSX/Helper/CellValueFormatter.php
+++ b/src/Reader/XLSX/Helper/CellValueFormatter.php
@@ -268,9 +268,13 @@ class CellValueFormatter
         $dateObj->modify('+'.$secondsRemainder.'seconds');
 
         if ($this->shouldFormatDates) {
-            $styleNumberFormatCode = $this->styleManager->getNumberFormatCode($cellStyleId);
-            $phpDateFormat = DateFormatHelper::toPHPDateFormat($styleNumberFormatCode);
+            //$styleNumberFormatCode = $this->styleManager->getNumberFormatCode($cellStyleId);
+            //$phpDateFormat = DateFormatHelper::toPHPDateFormat($styleNumberFormatCode);
+            // Toujours utiliser le format français complet
+            $phpDateFormat = "d/m/Y H:i:s";
             $cellValue = $dateObj->format($phpDateFormat);
+            // Enlever la composante heure si elle n'existe pas
+            $cellValue = preg_replace('/ 00:00:00$/', "", $cellValue);
         } else {
             $cellValue = $dateObj;
         }
diff --git a/src/Reader/XLSX/Manager/OptionsManager.php b/src/Reader/XLSX/Manager/OptionsManager.php
index b04b92c..5749f65 100644
--- a/src/Reader/XLSX/Manager/OptionsManager.php
+++ b/src/Reader/XLSX/Manager/OptionsManager.php
@@ -29,7 +29,7 @@ class OptionsManager extends OptionsManagerAbstract
     protected function setDefaultOptions()
     {
         $this->setOption(Options::TEMP_FOLDER, sys_get_temp_dir());
-        $this->setOption(Options::SHOULD_FORMAT_DATES, false);
+        $this->setOption(Options::SHOULD_FORMAT_DATES, true);
         $this->setOption(Options::SHOULD_PRESERVE_EMPTY_ROWS, false);
         $this->setOption(Options::SHOULD_USE_1904_DATES, false);
     }