未知的C＃类型

Question

I've a method exMethod that return the value in this way:

return new {name = name, surname = surname};

and I use this code

var person = exMethod();

but at this point how can I access to its fields? I've tried with

person.name

but is thrown the exception

'object' does not contain a definition for 'name'

Answer 1

Anonymous types can't be passed across the boundaries of a method without losing their type (they will revert to object ). Since you can't cast it, you are stuck.

You have to create a type to expose that to the outside of the creating method. (I don't want to mention dynamic as a solution)

Answer 2

you could do

dynamic person = exMethod();

but not recommended and is 'the easy way out' and you wouldn't have any compile time errors then. Another solution could be to use reflection but that can be heavy.

The best (safest, best practice) idea is probably to create a class to define the type that is being returned

class Foo {
    public string name {get;set;}
    public string surname{get;set;}
}

return new Foo(){ name = name, surname = surname }

then you would be able to use those properties

Answer 3

If you have control over exMethod , modify it as Patrick suggests .

If you don't and must accept it as an Object use dynamic instead of var :

 
 
 
 
  
  
  dynamic person = exMethod(); person.name;
 
 
  

Answer is worthless, comments are good, particularly @Servy's:

Anonymous classes are internal, so if it's in an API that you don't have access to then dynamic wouldn't work. It's only an option when you have control over the implementation of the method.