public void TestDependencyTest()
{
var emailLogger = new EmailLogger();
BetterCustomer customer = new BetterCustomer(emailLogger);
var otherLogger = new OtherLogger();
BetterCustomer otherCustomer = new BetterCustomer(otherLogger);
Assert.IsInstanceOfType(emailLogger, typeof(EmailLogger));
Assert.IsInstanceOfType(emailLogger, typeof(ILogger));
Assert.IsNotInstanceOfType(emailLogger, typeof(OtherLogger));
Assert.IsInstanceOfType(otherLogger, typeof(OtherLogger));
Assert.IsInstanceOfType(otherLogger, typeof(ILogger));
Assert.IsNotInstanceOfType(otherLogger, typeof(EmailLogger));
}
// e.g. when it is used:
private void UseDependencyInjectionForLogger()
{
var customer = new BetterCustomer(new EmailLogger());
customer.Add(new Database());
}
