aspnetboilerplate/aspnetboilerplate · error · Exception

Input types must be unique.There is already an input type…

Error message

Input types must be unique.There is already an input type named \"{inputTypeName}\"

What it means

AddAllowedInputType maintains a dictionary of allowed input types keyed by the input type's name; registering a second IInputType whose resolved name equals an existing one throws a plain Exception because input type names must be unique for lookup (GetOrNullAllowedInputType). Duplicate names would make name-based resolution ambiguous.

Solutions

1. Give each input type implementation a distinct, unique Name
2. Skip registration if _allowedInputTypes already contains the name
3. Rename one of the colliding input types (prefix with feature/module name)
4. Ensure PreInitialize/registration code runs only once per app start

Example fix

// before
public class DropdownInput : InputTypeBase { public override string Name => "combobox"; }
public class ComboboxInput : InputTypeBase { public override string Name => "combobox"; } // duplicate
// after
public class DropdownInput : InputTypeBase { public override string Name => "dropdown"; }
public class ComboboxInput : InputTypeBase { public override string Name => "combobox"; }

string name = InputTypeBase.GetName<TInputType>();
if (manager.GetOrNullAllowedInputType(name) != null) { return; } // already registered
manager.AddAllowedInputType<TInputType>();

bool IsUniqueName<T>() where T : IInputType { var n = InputTypeBase.GetName<T>(); return !string.IsNullOrWhiteSpace(n) && existingNames.All(x => x != n); }

try { manager.AddAllowedInputType<TInputType>(); } catch (Exception ex) when (ex.Message.StartsWith("Input types must be unique")) { // duplicate name — rename input type or skip registration }

When it happens

Trigger: Calling AddAllowedInputType<T>() with two different classes that resolve to the same input type name — e.g. two custom input types both returning Name = "checkbox", or re-registering the same input type twice in different modules' PreInitialize.

Common situations: Copy-pasted input type classes where the Name string wasn't changed; base/subclass pairs sharing the same Name value; module double-initialization running registration twice.

Understand the failure class

Background: "already exists" / EEXIST / FileAlreadyExistsException: what the 'file already exists' error means and how to fix it — this error's family across 37 libraries.

Related errors

• ArgumentNullException
• Entity already registered
• Setting group has already a Parent ().
• There is already a audit field configuration with name:
• There is already a filter with name:

AI-assisted analysis of aspnetboilerplate/aspnetboilerplate@2323c13a15 (2026-09-08). Data as JSON: /api/errors/7f4128c5f7d11f4a. Report an issue: GitHub.

Appendix: source

Thrown at src/Abp/DynamicEntityProperties/DynamicEntityPropertyDefinitionManager.cs:57

                using (var provider = _iocManager.ResolveAsDisposable<DynamicEntityPropertyDefinitionProvider>(providerType))
                {
                    provider.Object.SetDynamicEntityProperties(context);
                }
            }
        }

        public void AddAllowedInputType<TInputType>() where TInputType : IInputType
        {
            var inputTypeName = InputTypeBase.GetName<TInputType>();

            if (inputTypeName.IsNullOrWhiteSpace())
            {
                throw new ArgumentNullException(typeof(TInputType).FullName + "/" + nameof(inputTypeName));
            }

            if (_allowedInputTypes.ContainsKey(inputTypeName))
            {
                throw new Exception($"Input types must be unique.There is already an input type named \"{inputTypeName}\"");
            }

            _allowedInputTypes.Add(inputTypeName, typeof(TInputType));
        }

        public IInputType GetOrNullAllowedInputType(string name)
        {
            return _allowedInputTypes.ContainsKey(name)
                ? (IInputType)Activator.CreateInstance(_allowedInputTypes[name])
                : null;
        }

        public List<string> GetAllAllowedInputTypeNames()
        {
            return _allowedInputTypes.Keys.ToList();
        }

        public List<IInputType> GetAllAllowedInputTypes()

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