How can I pass in a func with a generic type parameter?

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死守一世寂寞
死守一世寂寞 2020-12-01 17:59

I like to send a generic type converter function to a method but I can\'t figure out how to do it.

Here\'s invalid syntax that explains what I like to achieve, the p

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  •  死守一世寂寞
    2020-12-01 18:14

    You cannot have instances of generic functions or actions - all type parameters are defined upfront and cannot be redefined by the caller.

    An easy way would be to avoid polymorphism altogether by relying on down-casting:

    public void SomeUtility(Func converter)
    {
        var myType = (MyType)converter(typeof(MyType), "foo");
    }
    

    If you want type safety, you need to defer the definition of the type parameters to the caller. You can do this by composing a generic method within an interface:

    public void SomeUtility(IConverter converter)
    {
        var myType = converter.Convert("foo");
    }
    
    interface IConverter
    {
       T Convert(object obj);
    }
    

    Edit:

    If the 'converter type' is known at the call-site, and only this type will be used inside the utility method, then you can define a generic type on the method and use that, just like other posters have suggested.

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