When new-able use new T(), otherwise use default(T)

Question

I am working on a C# generic function. When error, if the generic type can be new-able, return new T(), otherwise return default(T).

The code like this:

private T Func<T>()
{
    try
    {
        // try to do something...
    }
    catch (Exception exception)
    {
        if (T is new-able) // <---------- How to do this?
        {
            return new T();
        }
        else
        {
            return default(T);
        }
    }
}

I know it needs where T : new() for those using new T(). This question is, how to judge this on runtime?

Answer 1

You just need to check whether the type has a parameterless constructor. You do it by callingType.GetConstructor method with empty types as parameter.

var constructorInfo = typeof(T).GetConstructor(Type.EmptyTypes);
if(constructorInfo != null)
{
   //here you go
   object instance = constructorInfo.Invoke(null);
}