Question

我使用visual studio 2012在asp.net mvc 4中创建了一个Web api。我使用Post方法接收用户/调用应用程序发送的数据。

[HttpPost]
public HttpResponseMessage Post(Object model)
{
    HttpResponseMessage hrm;
    try
    {
        if (model == null)
        {
            hrm = new HttpResponseMessage(HttpStatusCode.NotFound);
            hrm.Content = new StringContent("Null request data");
            hrm.ReasonPhrase = "Incomming contract info is NULL";

            return hrm;
        }
        InputData IDat = JsonConvert.DeserializeObject<InputData>(model.ToString());
        ...

当我使用以下代码使用HttpClient.PostAsJsonAsync测试帖子到api时，

HttpClient hc = new HttpClient();
string resp = "";
if (idat.GetType().Name == "InputData")
{
    hc = new HttpClient();
    hc.BaseAddress = new Uri("http://localhost:49688/");
    hc.DefaultRequestHeaders.Accept.Clear();
    hc.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));

    var response = hc.PostAsJsonAsync("api/ ComputeFR", idat).Result;
    resp = response.Content.ReadAsStringAsync().Result;
    ...

web api收到JSON，上面的“model”不为null，它显示调用例程发送的JSON。发送的JSON如下，

{
   "UserId": "test",
   "pwd": "test123",
   "ContractParam": [
     {
       "ContractID": "00000",
       "Units": [
         {
           "UnitID": "11111111",
           "TypeCode": 25,
           "PracticeCode": 35,
           "InsuredShare": 1.0,
           "SaleDate": "20180315"
         }
       ],
       "Intervals": [
         {
           "IntervalStartDate": "20171101",
           "IntervalEndDate": "20171130"
         }
       ]
     }
   ]
}

当我用下面的R使用“POST”（httr包）调用web api时，Sample1.txt文件包含上面的json。

myjson <- read_file("C:\\Testing\\Sample1.txt")
# JSON encoded
url1 <- "http://localhost:49688/api/ComputeFR"
 postresult <- POST(url1, body = myjson, verbose())
output <- content(postresult)

R中的

verbose（）生成以下内容，

-> POST /api/ComputeFR HTTP/1.1
-> Host: localhost:49688
-> User-Agent: libcurl/7.53.1 r-curl/2.4 httr/1.3.1
-> Accept-Encoding: gzip, deflate
-> Accept: application/json, text/xml, application/xml, */*
-> Content-Length: 831
-> 
>> {
>>   "UserId": "test",
>>   "pwd": "test123",
>>   "ContractParam": [
>>     {
>>       "ContractID": "00000",
>>       "Units": [
>>         {
>>           "UnitID": "11111111",
>>           "TypeCode": 25,
>>           "PracticeCode": 35,
>>           "InsuredShare": 1.0,
>>           "SaleDate": "20180315"
>>         }
>>       ],
>>       "Intervals": [
>>         {
>>           "IntervalStartDate": "20171101",
>>           "IntervalEndDate": "20171130"
>>         }
>>       ]
>>     }
>>   ]
>> }

Web api然后返回以下

<- HTTP/1.1 404 Incomming contract info is NULL
<- Cache-Control: no-cache
<- Pragma: no-cache
<- Content-Length: 17
<- Content-Type: text/plain; charset=utf-8
<- Expires: -1
<- Server: Microsoft-IIS/10.0
<- X-AspNet-Version: 4.0.30319
<- X-SourceFiles: =?UTF-8?B?QzpcQ3JvcENvZGVcRmxleFJhdGVXZWJBcGlcRmxleFJhdGVXZWJBcGlcYXBpXEZsZXhSYXRl?=
<- X-Powered-By: ASP.NET
<- Date: Wed, 10 Jan 2018 15:28:41 GMT
<-

web api收到请求（我可以看到标题和内容长度=从R调用发送的内容）。但是“模型”始终为空。

有人可以帮我理解这个问题并为此提出解决方案。非常感谢你的时间和帮助。

Answer 1

尝试在R请求中将Content-Type标头设置为application / json。 PostAsJsonAsync可能会在您的c＃客户端中为您执行此操作。 Content-Type告诉端点您要发送的数据类型。接受说出你的回应。

从R

1 个答案: