如何伪造HttpContext进行单元测试？

public class MockHttpContext : HttpContextBase
{
    private readonly HttpRequestBase _request;
    private readonly HttpResponseBase _response;
    private readonly HttpSessionStateBase _session;

    public MockHttpContext(HttpRequestBase request, HttpResponseBase response, HttpSessionStateBase session)
    {
        _request = request;
        _response = response;
        _session = session;
    }

    public override HttpRequestBase Request => _request;
    public override HttpResponseBase Response => _response;
    public override HttpSessionStateBase Session => _session;
}

public class MockHttpRequest : HttpRequestBase
{
    private readonly Uri _url;

    public MockHttpRequest(Uri url)
    {
        _url = url;
    }

    public override Uri Url => _url;
}

public class MockHttpResponse : HttpResponseBase
{
    private readonly StringWriter _output;

    public MockHttpResponse(StringWriter output)
    {
        _output = output;
    }

    public override StringWriter Output => _output;
}

public class MockHttpSessionState : HttpSessionStateBase
{
    private readonly Dictionary<string, object> _sessionItems;

    public MockHttpSessionState()
    {
        _sessionItems = new Dictionary<string, object>();
    }

    public override object this[string name]
    {
        get => _sessionItems.ContainsKey(name) ? _sessionItems[name] : null;
        set => _sessionItems[name] = value;
    }
}

[Test]
public void MyTestMethod()
{
    // 创建伪造的HttpContext对象
    var request = new MockHttpRequest(new Uri("http://example.com"));
    var response = new MockHttpResponse(new StringWriter());
    var session = new MockHttpSessionState();
    var context = new MockHttpContext(request, response, session);

    // 调用被测试的方法或类，并传递伪造的HttpContext对象
    var result = MyTestClass.MyTestMethod(context);

    // 断言结果是否符合预期
    Assert.AreEqual("expected result", result);
}