Cannot create an instance of interface

• Jun 07, 2019

CodeRush Classic shows the Cannot create an instance of interface code issue if an instance creation statement references an interface.

Fix

Create an instance of a class implementing the current interface.

Purpose

Highlights the instance creation statements, which would cause the Cannot create an instance of the abstract class or interface compilation error.

Example

C#

interface IMyClass
{
    void OutputText(string text);
}
public class TestClass
{
    public TestClass()
    {
        IMyClass objVar = new │IMyClass();
    }
}

Fix:

C#

interface IMyClass
{
    void OutputText(string text);
}
class MyClass: IMyClass
{
    public override void OutputText(string text)
    {
        Console.Write(text);
    }
}
public class TestClass
{
    public TestClass()
    {
        IMyClass objVar = new MyClass();
    }
}