Modification of the property Mail. Now, we want this property to never be empty or null because it will serve for login

MCTG/MCTGLib/User.cs

@@ -37,7 +37,7 @@ namespace MCTGLib
                 {
                     throw new ArgumentNullException("Erreur pour la photo d'utilisateur!");
                 }
-            
+            }
           
         }
         /// <summary>
@@ -67,15 +67,27 @@ namespace MCTGLib
             {
                 if (string.IsNullOrWhiteSpace(value))
                 {
-                    throw new ArgumentNullException("Il y a une erreur de Prénom d'utilisateur");
+                    throw new ArgumentNullException("Il y a une erreur de Prénom d'utilisateur.");
                 }
                 surname = value;
             }
         }
+        /// <summary>
+        /// Property to get mail of users and a setter 
+        /// </summary>
+        /// <exception cref="ArgumentNullException" >User's mail will serve to log the user. So there's no setter, just an init. User will enter one time his email at his
+        /// account creation.</exception>
         public string Mail
         {
             get { return mail; }
-            private set { mail = value; }
+            init
+            {
+                if (string.IsNullOrWhiteSpace(value))
+                {
+                    throw new ArgumentNullException("Il y a une erreur de Mail d'utilisateur.");
+                }
+                mail = value;
+            }
         }
 
 
@@ -95,6 +107,9 @@ namespace MCTGLib
         /// <summary>
         /// Construtors of user.
         /// </summary>
+        /// <param name="name">The name of the user</param>
+        /// <param name="surname">The surname of the user</param>
+        /// <param name="mail">The user needs an email to login. </param>
         public User(string name, string surname, string mail)
         {
             Name = name;