这是一个不需要模拟的解决方案。您实现了WebRequest 的所有三个组件：IWebRequestCreateWebRequest 和WebResponse。见下文。我的示例生成失败的请求（通过抛出 WebException），但应该能够对其进行调整以发送“真实”响应：
class WebRequestFailedCreate : IWebRequestCreate {
HttpStatusCode status;
String statusDescription;
public WebRequestFailedCreate(HttpStatusCode hsc, String sd) {
status = hsc;
statusDescription = sd;
}
#region IWebRequestCreate Members
public WebRequest Create(Uri uri) {
return new WebRequestFailed(uri, status, statusDescription);
}
#endregion
}
class WebRequestFailed : WebRequest {
HttpStatusCode status;
String statusDescription;
Uri itemUri;
public WebRequestFailed(Uri uri, HttpStatusCode status, String statusDescription) {
this.itemUri = uri;
this.status = status;
this.statusDescription = statusDescription;
}
WebException GetException() {
SerializationInfo si = new SerializationInfo(typeof(HttpWebResponse), new System.Runtime.Serialization.FormatterConverter());
StreamingContext sc = new StreamingContext();
WebHeaderCollection headers = new WebHeaderCollection();
si.AddValue("m_HttpResponseHeaders", headers);
si.AddValue("m_Uri", itemUri);
si.AddValue("m_Certificate", null);
si.AddValue("m_Version", HttpVersion.Version11);
si.AddValue("m_StatusCode", status);
si.AddValue("m_ContentLength", 0);
si.AddValue("m_Verb", "GET");
si.AddValue("m_StatusDescription", statusDescription);
si.AddValue("m_MediaType", null);
WebResponseFailed wr = new WebResponseFailed(si, sc);
Exception inner = new Exception(statusDescription);
return new WebException("This request failed", inner, WebExceptionStatus.ProtocolError, wr);
}
public override WebResponse GetResponse() {
throw GetException();
}
public override IAsyncResult BeginGetResponse(AsyncCallback callback, object state) {
Task<WebResponse> f = Task<WebResponse>.Factory.StartNew (
_ =>
{
throw GetException();
},
state
);
if (callback != null) f.ContinueWith((res) => callback(f));
return f;
}
public override WebResponse EndGetResponse(IAsyncResult asyncResult) {
return ((Task<WebResponse>)asyncResult).Result;
}
}
class WebResponseFailed : HttpWebResponse {
public WebResponseFailed(SerializationInfo serializationInfo, StreamingContext streamingContext)
: base(serializationInfo, streamingContext) {
}
}
您必须创建一个HttpWebResponse 子类，否则您无法创建一个。
棘手的部分（在GetException() 方法中）是输入您无法覆盖的值，例如StatusCode 这就是我们最好的伙伴SerializaionInfo 的用武之地！这是您提供无法覆盖的值的地方。显然，覆盖（HttpWebResponse 的）您可以的部分，以完成剩下的工作。
我是如何在所有AddValue() 调用中获得“名称”的？从异常消息！很高兴能轮流告诉我每个人，直到我开心为止。
现在，编译器会抱怨“过时”，但这仍然有效，包括 .NET Framework 版本 4。
这是一个（通过）测试用例供参考：
[TestMethod, ExpectedException(typeof(WebException))]
public void WebRequestFailedThrowsWebException() {
string TestURIProtocol = TestContext.TestName;
var ResourcesBaseURL = TestURIProtocol + "://resources/";
var ContainerBaseURL = ResourcesBaseURL + "container" + "/";
WebRequest.RegisterPrefix(TestURIProtocol, new WebRequestFailedCreate(HttpStatusCode.InternalServerError, "This request failed on purpose."));
WebRequest wr = WebRequest.Create(ContainerBaseURL);
try {
WebResponse wrsp = wr.GetResponse();
using (wrsp) {
Assert.Fail("WebRequest.GetResponse() Should not have succeeded.");
}
}
catch (WebException we) {
Assert.IsInstanceOfType(we.Response, typeof(HttpWebResponse));
Assert.AreEqual(HttpStatusCode.InternalServerError, (we.Response as HttpWebResponse).StatusCode, "Status Code failed");
throw we;
}
}