使用HttpClient,如何防止自动重定向并获取原始状态代码并在301的情况下转发Url

Question

我有以下方法返回Http status code给定的Url:

public static async void makeRequest(int row, string url)
{
    string result;
    Stopwatch sw = new Stopwatch(); sw.Start();

    try
    {
        using (HttpClient client = new HttpClient())
        {
            HttpResponseMessage response = new HttpResponseMessage();
            response = await client.GetAsync(url);

            // dump contents of header
            Console.WriteLine(response.Headers.ToString());

            if (response.IsSuccessStatusCode)
            {
                result = ((int)response.StatusCode).ToString();
            }
            else
            {
                result = ((int)response.StatusCode).ToString();
            }
        }
    }
    catch (HttpRequestException hre)
    {
        result = "Server unreachable";
    }

    sw.Stop();
    long time = sw.ElapsedTicks / (Stopwatch.Frequency / (1000L * 1000L));

    requestComplete(row, url, result, time);
}

它适用于200/ 404etc,但是在301代码的情况下,我认为返回的结果是已经重定向的(200)结果,而不是301应该返回的实际结果,并且具有包含重定向将指向的位置的标头.

我在其他.Net Web请求类中看到了类似的东西,并且将某种allowAutoRedirect属性设置为false.如果这是沿着正确的路线,有人能告诉我正确的选择HttpClient吗？

这篇文章有关于上面的allowAutoRedirect概念的信息,我的意思是

另外,我怎么能让这种方法返回301s而不是200s我认为真实的网址301s呢？

Answer 1

我发现这样做的方法是HttpClientHandler在构造函数中创建一个实例并将其传递给它HttpClient

public static async void makeRequest(int row, string url)
{
    string result;
    Stopwatch sw = new Stopwatch(); sw.Start();

    // added here
    HttpClientHandler httpClientHandler = new HttpClientHandler();
    httpClientHandler.AllowAutoRedirect = false;

    try
    {
        // passed in here
        using (HttpClient client = new HttpClient(httpClientHandler))
        {

        }

有关详细信息,请参见此处