想通过OCR服务来做身份证识别，但执行到hc.GetData()就出现“500 内部服务器错误”，请教是不是代码不正确？

Foxtable使用hc.GetData()，但示例代码用的是httpClient.PostAsync()，是不是这里出问题，该如何定呢？多谢。

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以下为Foxtable代码：

Dim hc As New HttpClient(http://netocr.com/api/recog.do)

\'设置参数
hc.Timeout = 5 \'秒
hc.Headers.Add("user-agent", "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/36.0.1985.143 Safari/537.36")

hc.FormData.Add("XXXXX","key")
hc.FormData.Add("XXXXX","secret")
hc.FormData.Add("2","typeId")

\'添加文件
hc.Files.Add("file","C:\\图片2\\IMAG3622.jpg")

Output.Show(hc.GetData())

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以下为OCR示例代码：

Public String PostIdCardDataToXiangYun(String filePath)
{
 String url = "http://netocr.com/api/recog.do";
 System.Net.Http.HttpClient httpClient = new System.Net.Http.HttpClient();
 httpClient.MaxResponseContentBufferSize = 256000;
 httpClient.DefaultRequestHeaders.Add("user-agent", "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/36.0.1985.143 Safari/537.36");
 FileStream fileStream = new FileStream(filePath, FileMode.Open, FileAccess.Read);
 System.Net.Http.MultipartFormDataContent content = new System.Net.Http.MultipartFormDataContent();
 //增加文件数据
 content.Add(new System.Net.Http.StreamContent(fileStream), "file", "idcard.jpg");
 //增加参数
 content.Add(new StringContent("xxxx"),"key");
 content.Add(new StringContent("ddddd"),"secret");
 //二代身份证正面识别
 content.Add(new StringContent("2"),"typeId");
 content.Add(new StringContent("json"),"format");
 System.Net.Http.HttpResponseMessage response = httpClient.PostAsync(new Uri(url), content).Result;
 string result = response.Content.ReadAsStringAsync().Result;
 fileStream.Close();
 return result;
}