BDD规范流对象引用未设置为ObjectContainer.RegisterInstanceAs中对象的实例

我已经重新排列了我的类文件和Webdriver变量，这样我就可以使用上下文注入在步骤之间共享Webdrive变量。在我使用SetupFixture、Setup和TearDown之前，这对BDD来说是不正确的。现在尝试使用BeforeAllTests、BeforeTestRun等进行上下文注入。我得到错误：

System.NullReferenceException: Object reference not set to an instance of an object

错误所在的行突出显示：

[BeforeScenario]
        public void RunBeforeScenario()
        {
            objectContainer.RegisterInstanceAs<SeleniumContext>(seleniumContext);
        }

我的setup.cs实现是：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using TechTalk.SpecFlow;
using OpenQA.Selenium;
using OpenQA.Selenium.Support.PageObjects;
using OpenQA.Selenium.Firefox;
using SearchTest.Setup;
using BoDi;
using SearchTest.WebDriver;

namespace SearchTest.Setup
{
    [Binding]
    public class BeforeAllTests
    {
        private readonly IObjectContainer objectContainer;
        private static SeleniumContext seleniumContext;
        public BeforeAllTests(IObjectContainer container)
        {
            this.objectContainer = objectContainer;
        }
        [BeforeTestRun]
        public static void RunBeforeAllTests()
        {
            seleniumContext = new SeleniumContext();
        }
        [BeforeScenario]
        public void RunBeforeScenario()
        {
            objectContainer.RegisterInstanceAs<SeleniumContext>(seleniumContext);
        }
    }
}

我的主页类HomePage.cs的实现是：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using OpenQA.Selenium;
using OpenQA.Selenium.Support.PageObjects;
using OpenQA.Selenium.Firefox;
using NUnit.Framework;
using SearchTest.Setup;
using SearchTest.WebDriver;
using TechTalk.SpecFlow;
using BoDi;

namespace SearchTest.PageObjects
{
    [Binding]
    public class HomePage : PageObjectBase 
    {
        private SeleniumContext seleniumContext;
        //private IWebDriver driver{ get; set; }
        [FindsBy(How = How.XPath, Using = ".//TITLE")]
        public IWebElement Title{ get; set; }
        // search text field on the homepage
        //[FindsBy(How= How.Id, Using="twotabsearchtextbox")]
        //private IWebElement Searchfield_ID { get; set; }
        [FindsBy(How = How.XPath, Using = ".//*[@id='twotabsearchtextbox']")]
        private IWebElement Searchfield_XPATH { get; set; }
        [FindsBy(How = How.Id, Using = "nav-search-submit-text")]
        private IWebElement SearchButton { get; set; }
        [FindsBy(How = How.XPath, Using = ".//*[@id='nav-search']/form/div[2]/div/input")]
        private IWebElement searchButton_Xpath {get; set;}
//        public HomePage(IWebDriver driver)
        public HomePage(SeleniumContext seleniumContext)
            /*This is to reference the PageObjectBase Class.  Passing in the Title of the 
             * page that is expected for the HomePage to ensure the correct Page is loaded
             * before starting any tests.
             */
            //: base("Amazon.co.uk: Low Prices in Electronics, Books, Sports Equipment & more")
            : base(seleniumContext)

        {
           //driver = new FirefoxDriver();
           //Console.Out.WriteLine("from Homepage Constructor Driver.title in SearchResultsPage class = " + driver.Title);
           //driver.Manage().Timeouts().ImplicitlyWait(TimeSpan.FromSeconds(5)); // Set implicit wait timeouts to 5 secs
           //PageFactory.InitElements(driver, this);
            this.seleniumContext = seleniumContext;
            PageFactory.InitElements(seleniumContext.driver, this);
        }
    public void goToURL() {
        //driver.Navigate().GoToUrl("http://www.amazon.co.uk");
    }
    public void EnterSearchText(String text)
        {
            Searchfield_XPATH.SendKeys(text);
        }
    public SearchResultsPage click_search_button() {
        searchButton_Xpath.Click();
        return new SearchResultsPage(seleniumContext);
    }
   }   
}

Steps类SearchSteps.cs的实现是：

using System;
using TechTalk.SpecFlow;
using OpenQA.Selenium;
using OpenQA.Selenium.Firefox;
using NUnit.Framework;
using SearchTest.PageObjects;
using SearchTest.WebDriver;
namespace SearchTest
{
    [Binding]
    public class SearchSteps
    {
        private SeleniumContext seleniumContext;
        private IWebDriver driver { get; set; }
        PageObjects.HomePage home_page { get; set; }
        private SearchResultsPage search_results_page;
    [Given(@"I navigate to the page ""(.*)""")]
    public void GivenINavigateToThePage(string p0)
        home_page = new PageObjects.HomePage(seleniumContext);
        //home_page.goToURL();
    }
    [Given(@"I see the page is loaded")]
    public void GivenISeeThePageIsLoaded()
    {
        //Assert.AreEqual("http://localhost:8080: PS4 products", driver.Title);
    }
    [When(@"I enter Search Keyword in the Search Text box")]
    public void WhenIEnterSearchKeywordInTheSearchTextBox(Table table)
    {
        //string search_text = table.Rows[0]["Keyword"].ToString();
        //driver.FindElement(By.Id("twotabsearchtextbox")).SendKeys(search_text);
        //SearchResultsPage SearchResultsPage = home_page.EnterSearchText("F1");
        home_page.EnterSearchText("F1");
    }
    [When(@"I click on Search Button")]
    public void WhenIClickOnSearchButton()
    {
        //driver.FindElement(By.Name("BtnG")).Click();
        search_results_page = home_page.click_search_button();
    }
    [Then(@"Search items shows the items related to PS4")]
    public void ThenSearchItemsShowsTheItemsRelatedToPS4()
    {
        //Assert.AreEqual("PS4", driver.FindElement(By.XPath(".//*[@id='desktop-auto-sparkle-multi']/div/a")).Text);
        //Assert.AreEqual("PS4", driver.FindElement(By.XPath("//h2[contains(text(), "PS4")]")));
        search_results_page.get_search_result_title();
    }
  }
}

我该如何解决这个问题？我认为这是在抱怨objectContainer.RegisterInstanceAs没有任何值，它是Null。它还没有实例化？

谢谢，Riaz

public BeforeAllTests(IObjectContainer container)
{
    this.objectContainer = objectContainer;
}

public BeforeAllTests(IObjectContainer container)
{
    this.objectContainer = container;
}