尝试使用 C# 连接到 Dropbox API v2 在所有尝试中收到 400 错误

Question

新的 Dropbox API 文档位于：

https://blogs.dropbox.com/developers/2015/04/a-preview-of-the-new-dropbox-api-v2/

我正在尝试执行一个简单的元数据调用，但收效甚微。这是我正在使用的代码：

    private void go()
    {
        var httpWebRequest = (HttpWebRequest)WebRequest.Create("https://api.dropbox.com/2-beta/files/get_metadata");
        httpWebRequest.ContentType = "text/json";
        httpWebRequest.Method = "POST";
        httpWebRequest.Headers.Add("Authorization: Bearer xxxxxxxxxxxxxxxxxxx");

        using (var streamWriter = new StreamWriter(httpWebRequest.GetRequestStream()))
        {
            string json = "{\"path\": \"/avatar_501.png\"}";

            streamWriter.Write(json);
            streamWriter.Flush();
            streamWriter.Close();
        }

        var httpResponse = (HttpWebResponse)httpWebRequest.GetResponse();
        using (var streamReader = new StreamReader(httpResponse.GetResponseStream()))
        {
            var result = streamReader.ReadToEnd();
            this.TextBox1.Text = result;
        }
    }

如有任何帮助，我们将不胜感激！

Answer 1

如果您尝试此代码，您将看到 400 响应的正文，它告诉您 text/json 不是有效的 Content-Type。我将您的代码转换为控制台应用程序，并使用 Newtonsoft.Json 进行 JSON 序列化。否则，你的代码和我的代码之间的唯一区别是添加了异常处理来获取 400 的主体。

class Program
{
    static void Main(string[] args)
    {
        var httpWebRequest = (HttpWebRequest)WebRequest.Create("https://api.dropbox.com/2-beta/files/get_metadata");
        httpWebRequest.ContentType = "text/json";
        httpWebRequest.Method = "POST";
        httpWebRequest.Headers.Add("Authorization: Bearer <REDACTED>");

        using (var streamWriter = new StreamWriter(httpWebRequest.GetRequestStream()))
        {
            streamWriter.Write(JsonConvert.SerializeObject(new {
                path = "/avatar_501.png"
            }));
        }

        HttpWebResponse response;

        try
        {
            response = (HttpWebResponse)httpWebRequest.GetResponse();
        }
        catch (WebException e)
        {
            response = (HttpWebResponse)e.Response;
        }

        Console.WriteLine("Status code: {0}", (int)response.StatusCode);
        using (var streamReader = new StreamReader(response.GetResponseStream()))
        {
            Console.WriteLine(streamReader.ReadToEnd());
        }

        Console.ReadLine();
    }
}

输出结果如下：

Status code: 400
Error in call to API function "files/get_metadata": Bad HTTP "Content-Type" header: "text/json".  Expecting one of "application/json", "application/json; charset=utf-8", "text/plain; charset=dropbox-cors-hack".

将 Content-Type 更改为 application/json 会导致调用成功。

尝试使用 C# 连接到 Dropbox API v2 在所有尝试中收到 400 错误

Trying to connect to the Dropbox API v2 using C# Receive 400 error on all attempts

c#

json

dropbox