diff --git a/business/Task.php b/business/Task.php
index bb84679..cdea1fb 100644
--- a/business/Task.php
+++ b/business/Task.php
@@ -10,7 +10,7 @@
 	    private string $idlist; // # id associating task to list
         private bool $isDone; // # si la tache est complete
         
-	function __construct($titre,$description,$priorite,$idl,$dateDeb=null,$dateFin=null,$isDone=false,$id=0) {
+	function __construct($titre,$description,$priorite,$idl,$dateDeb="",$dateFin="",$isDone=false,$id=0) {
             # if id = 0, on veut donc creer une nouvelle tache
             # qui n'est pas encore dans la base de donnée et donc
             # le id sera fait avec le auto increment
diff --git a/controller/VisitorCtrl.php b/controller/VisitorCtrl.php
index 8fd2f82..6951be5 100644
--- a/controller/VisitorCtrl.php
+++ b/controller/VisitorCtrl.php
@@ -88,6 +88,7 @@ class VisitorCtrl
             }
             
         } catch (Exception $e) {
+            var_dump($_POST);
             $TMessage[] = $e->getMessage();
             require($this->TabVues["erreur"]); 
         }
diff --git a/model/TaskModel.php b/model/TaskModel.php
index 748a3c5..1a63606 100644
--- a/model/TaskModel.php
+++ b/model/TaskModel.php
@@ -13,7 +13,7 @@ class TaskModel
         $this->gtw= new TaskGateway($con);
     }
 
-    public function addTask($titre,$desc,$priorite,$idList,$dateDeb=null,$dateFin=null,$isDone=false,$id=0)
+    public function addTask($titre,$desc,$priorite,$idList,$dateDeb="",$dateFin="",$isDone=false,$id=0)
     {
         $t = new Task($titre,$desc,$priorite,$idList,$dateDeb,$dateFin,$isDone,$id);
         $this->gtw->insertT($t);