Fix EditProspectDialog: update NumericEdit to handle null Foodsharing-ID correctly

FoodsharingSiegen.Contracts/Entity/User.cs

@@ -42,7 +42,12 @@ namespace FoodsharingSiegen.Contracts.Entity
             {
                 if (string.IsNullOrWhiteSpace(Groups)) return new List<UserGroup>();
                 var stringList = Groups.Split(",");
-                var enumList = stringList.Where(x => !string.IsNullOrWhiteSpace(x)).Select(Enum.Parse<UserGroup>).ToList();
+                var enumList = stringList
+                    .Where(x => !string.IsNullOrWhiteSpace(x))
+                    .Select(x => Enum.TryParse<UserGroup>(x.Trim(), out var result) ? result : (UserGroup?)null)
+                    .Where(x => x.HasValue)
+                    .Select(x => x!.Value)
+                    .ToList();
                 return enumList;
             }
             set => Groups = string.Join(",", value);

FoodsharingSiegen.Contracts/Helper/AttributeExtensions.cs

@@ -34,6 +34,7 @@ namespace FoodsharingSiegen.Contracts.Helper
         {
             var type = enumVal.GetType();
             var memInfo = type.GetMember(enumVal.ToString());
+            if (memInfo.Length == 0) return null;
             var attributes = memInfo[0].GetCustomAttributes(typeof(T), false);
             return attributes.Length > 0 ? (T)attributes[0] : null;
         }

FoodsharingSiegen.Server/Dialogs/EditProspectDialog.razor

@@ -11,7 +11,7 @@
     <div class="col">
         <Field>
             <FieldLabel>Foodsharing-ID</FieldLabel>
-            <NumericEdit TValue="int?" Value="Prospect.FsId" ValueChanged="@((int? v) => Prospect.FsId = v ?? 0)"></NumericEdit>
+            <NumericEdit TValue="int?" Value="@(Prospect.FsId == 0 ? (int?)null : Prospect.FsId)" ValueChanged="@((int? v) => Prospect.FsId = v ?? 0)"></NumericEdit>
         </Field>
     </div>
 </div>