我正在尝试使用HttpWebRequest验证Url的存在性。 我找到了一些基本上执行此操作的示例:
HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(Url);
request.Method = "HEAD";
using (HttpWebResponse response = request.GetResponse() as HttpWebResponse)
{
return response.StatusCode;
}
然而,如果URL确实存在问题,它不会返回响应,而是抛出异常。
我将我的代码修改为以下内容:
try
{
HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(Url);
request.Method = "HEAD";
using (HttpWebResponse response = request.GetResponse() as HttpWebResponse)
{
return response.StatusCode;
}
}
catch (System.Net.WebException ex)
{
var response = ex.Response as HttpWebResponse;
return response == null ? HttpStatusCode.InternalServerError : response.StatusCode;
}
这似乎最终做到了我想要的。
但是我想知道为什么请求会抛出异常而不返回带有未找到状态代码的响应?