minor #10382 Update upload_file.rst for handling FileException (LS05)

This PR was submitted for the master branch but it was squashed and merged into the 2.8 branch instead (closes #10382).

Discussion
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Update upload_file.rst for handling FileException

#9642
Handled FileException in coding examples. We need to discuss how to handle specific file exceptions ;)

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Commits
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0a5e663 Update upload_file.rst for handling FileException

Author: javiereguiluz

controller/upload_file.rst

@@ -123,11 +123,15 @@ Finally, you need to update the code of the controller that handles the form::
 
                 $fileName = $this->generateUniqueFileName().'.'.$file->guessExtension();
 
-                // moves the file to the directory where brochures are stored
-                $file->move(
-                    $this->getParameter('brochures_directory'),
-                    $fileName
-                );
+                // Move the file to the directory where brochures are stored
+                try {
+                    $file->move(
+                        $this->getParameter('brochures_directory'),
+                        $fileName
+                    );
+                } catch (FileException $e) {
+                    // ... handle exception if something happens during file upload
+                }
 
                 // updates the 'brochure' property to store the PDF file name
                 // instead of its contents
@@ -229,7 +233,11 @@ logic to a separate service::
         {
             $fileName = md5(uniqid()).'.'.$file->guessExtension();
 
-            $file->move($this->getTargetDirectory(), $fileName);
+            try {
+                $file->move($this->getTargetDir(), $fileName);
+            } catch (FileException $e) {
+                // ... handle exception if something happens during file upload
+            }
 
             return $fileName;
         }