c# - HttpClient 响应内容可以为空吗？

Question

当收到 HttpResponseMessage来自 HttpClient , 是否有任何情况下其 Content可能是 null ?

HttpClient client = new HttpClient();
HttpResponseMessage response = await client.GetAsync("https://www.stackoverflow.com/");
if (response.Content == null) {
    // Can this happen?
}
else
{
    string responseBody = await response.Content.ReadAsStringAsync();
    // ...
}

如果你认为可以是 null ，请提供一个例子来重现它。

我尝试了很多东西，但无法获得 null :

╔═══════════════════════╦═════════════════════════════════╦═══════════════════════╗
║        Request        ║            Response             ║        Content        ║
╠═══════════════════════╬═════════════════════════════════╬═══════════════════════╣
║ GET  http             ║ 200 OK, a response              ║ The response          ║
║ GET  http             ║ 200 OK, empty response          ║ Empty string          ║
║ GET  http             ║ 204 No Response, empty response ║ Empty string          ║
║ GET  http             ║ 400 Bad Request, a response     ║ The response          ║
║ GET  http             ║ 400 Bad Request, empty response ║ Empty string          ║
║ GET  http             ║ 500 Bad Request, empty response ║ Empty string          ║
║ HEAD http             ║ 200 OK, empty response          ║ Empty string          ║
║ OPTIONS http          ║ 200 OK, empty response          ║ Empty string          ║
║ GET  http, bad DNS    ║ (never hit)                     ║ HttpRequestException  ║
║ GET  http, bad scheme ║ (never hit)                     ║ ArgumentException     ║
║ GET  http             ║ Never respond                   ║ TaskCanceledException ║
╚═══════════════════════╩═════════════════════════════════╩═══════════════════════╝

Answer 1

如 MSDN says ，是的，它可以为空，但你应该使用 EnsureSuccessStatusCode检查响应是否有效