How do I check if a type provides a parameterless constructor?

by

The Type class is reflection. You can do:

Type theType = myobject.GetType(); // if you have an instance
// or
Type theType = typeof(MyObject); // if you know the type

var constructor = theType.GetConstructor(Type.EmptyTypes);

It will return null if a parameterless constructor does not exist.

If you also want to find private constructors, use the slightly longer:

var constructor = theType.GetConstructor(
  BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic, 
  null, Type.EmptyTypes, null);

There’s a caveat for value types, which aren’t allowed to have a default constructor. You can check if you have a value type using the Type.IsValueType property, and create instances using Activator.CreateInstance(Type);

More Related Contents:

  1. How to create a new object instance from a Type
  2. Testing if object is of generic type in C#
  3. How to call generic method with a given Type object? [duplicate]
  4. Getting a System.Type from type’s partial name
  5. Determine if a type is static
  6. How do I use reflection to call a generic method?
  7. What’s the difference between an object initializer and a constructor?
  8. How costly is .NET reflection?
  9. Getting all types in a namespace via reflection
  10. Generics in C#, using type of a variable as parameter [duplicate]
  11. Read the value of an attribute of a method
  12. How does WCF deserialization instantiate objects without calling a constructor?
  13. GetMethod for generic method [duplicate]
  14. Is there an alternative to bastard injection? (AKA poor man’s injection via default constructor)
  15. AddEventHandler using reflection
  16. .NET : How do you get the Type of a null object?
  17. How to hide public methods from IntelliSense
  18. How to find out if a property is an auto-implemented property with reflection?
  19. How to get MethodInfo of interface method, having implementing MethodInfo of class method?
  20. How to switch between “possible” type of an object? [duplicate]
  21. what is ‘this’ constructor, what is it for
  22. Finding property differences between two C# objects
  23. Create object instance of a class from its name in string variable
  24. Automatically implemented property in struct can not be assigned
  25. Look if a method is called inside a method using reflection
  26. Using Reflection to create a DataTable from a Class?
  27. Get private Properties/Method of base-class with reflection
  28. What is the function of the “this” keyword in a constructor?
  29. Reflecting a private field from a base class
  30. Two Types not equal that should be

Leave a Comment