C#: Cannot create an instance of the abstract class or interface

Question

i'm using a web service from HotelsPro and trying to create an instance but it gives me an error:

Cannot create an instance of the abstract class or interface 'HotelsPro.hotelsProSvc.b2bHotelSOAPPortType'

here is what i'm trying to do.

FORM1.CS

hotelsProSvc.b2bHotelSOAPPortType a = new b2bHotelSOAPPortType(); getAvailableHotelResponse getres = new getAvailableHotelResponse(); getres=a.getAvailableHotel(apiKey, "A990", checkIn, checkOut, "EUR", "UK", false, rooms, f);

Answer 1

In C# it is not possible to create an instance of an abstract class or interface.
b2bHotelSOAPPortType is either an interface or an abstract class. If you intend on creating a new object in this way (rather than using dependency injection for instance) then you must find a concrete class that implements b2bHotelSOAPPortType and new that.

For example

hotelsProSvc.b2bHotelSOAPPortType a = new Concreteb2bHotelSOAPPortType();

assuming Concreteb2bHotelSOAPPortType implements b2bHotelSOAPPortType.

A better approach would be to set up the relationship between these two classes in a DI container like Autofaq.

If b2bHotelSOAPPortType is an interface then it would be implemented thus

interface b2bHotelSOAPPortType {

}

if it is an abstract class then thus

abstract class b2bHotelSOAPPortType  {

}

What you need is to find a class that either implements b2bHotelSOAPPortType directly or indirectly. If it implements it directly it will look like this

class Concreteb2bHotelSOAPPortType : b2bHotelSOAPPortType {

}

If you are using Visual Studio you will be able to find which classes implement this interface or abstract class pretty easily.

Answer 2

Abstract classes or interfaces cannot be instanciated.

You'll have to instanciate a class that inherits from this class (or implements that interface).