public void Delete3DPrinter_ShouldReturnOK() { // Arrange this.dbContext.ThreeDPrinters.Add(new ThreeDPrinter() { Id = 1 }); this.dbContext.SaveChanges(); var service = new ThreeDPrinterService(this.dbContext); // Act service.Delete3DPrinters(1); bool isDeleted = this.IsDeleted(); // Assert Assert.AreEqual(true, isDeleted); }