Gestion de champs null sur les interactoins

Resources/config/doctrine/Scorm2004.Scorm2004Interaction.orm.xml

@@ -11,12 +11,12 @@
     <field name="identifier" type="string" column="identifier" length="255" nullable="false"/>
     <field name="type" type="string" column="type" length="50" nullable="false"/>
     <field name="weighting" type="float" column="weighting" nullable="false"/>
-    <field name="result" type="string" column="result" length="50" nullable="false"/>
-    <field name="description" type="text" column="description" nullable="false"/>
-    <field name="student_response" type="text" column="student_response" nullable="false"/>
-    <field name="correct_responses" type="text" column="correct_responses" nullable="false"/>
-    <field name="time" type="datetime" column="time" nullable="false"/>
-    <field name="latency" type="float" column="latency" nullable="false"/>
+    <field name="result" type="string" column="result" length="50" nullable="true"/>
+    <field name="description" type="text" column="description" nullable="true"/>
+    <field name="student_response" type="text" column="student_response" nullable="true"/>
+    <field name="correct_responses" type="text" column="correct_responses" nullable="true"/>
+    <field name="time" type="datetime" column="time" nullable="true"/>
+    <field name="latency" type="float" column="latency" nullable="true"/>
     
     <!-- item sur lequel l'essai est tenté -->
     <field name="itemIdentifier" type="string" column="item_identifier" length="255" nullable="false"/>

Tools/UnicodeTools.php

@@ -7,14 +7,16 @@ class UnicodeTools
 
     public static function strToUTF8($value)
     {
-        $encoding = self::getEncoding($value);
-
-        if ($encoding == 'UTF-8') {
-            return $value;
+        if (!empty($value)) {
+            $encoding = self::getEncoding($value);
+
+            if ($encoding == 'UTF-8') {
+                return $value;
+            }
+            
+            $value = @mb_convert_encoding($value, 'UTF-8', $encoding);
         }
         
-        $value = @mb_convert_encoding($value, 'UTF-8', $encoding);
-        
         return $value;
     }