返回從網頁API C＃

Question

響應數組我試圖創建一個Web API，它調用其他服務，並返回響應的陣列。被叫服務返回響應。我能夠從被叫服務中獲取單個項目。但不知道如何構建數組項並返回來自我創建的API的響應。

的JSON從服務返回的樣子

{ 
"cr_response": { 
    "details": [{ 
     "name": "Req", 
     "fields": [{ 
       "value": "Prj0\r\nPrj1", 
       "name": "Project" 
      }, 
      { 
       "value": "October 13, 2017 14:18", 
       "name": "Submitted" 
      }, 
      { 
       "value": "John", 
       "name": "Rec Name" 
      } 
     ] 
    }], 
    "cr_metadata": {} 
} 
} 

而POCO類看起來像

public class Field 
{ 
    public string value { get; set; } 
    public string name { get; set; } 
} 

public class Detail 
{ 
    public string name { get; set; } 
    public List<Field> fields { get; set; } 
} 

public class CrMetadata 
{ 
} 

public class CrResponse 
{ 
    public List<Detail> details { get; set; } 
    public CrMetadata cr_metadata { get; set; } 
} 

public class RootObject 
{ 
     public CrResponse cr_response { get; set; } 
} 

下面是調用服務和檢索來自服務的響應代碼

var response = await iLab_client.GetAsync(uri); 
var datafile = await response.Content.ReadAsStringAsync(); 
var returnDataObj = JsonConvert.DeserializeObject<DTO.RootObject>(datafile); 

foreach (var form in returnDataObj.cr_response.details) 
{ 
    name_response = form.name; 
    return Ok(name_response); 
} 

在這裏，我可以從細節訪問的名字，但不知道如何我可以訪問字段中的所有名稱和值並將其構造成一個數組。並將其作爲JSON響應發送。 我試着像

  foreach (var form in returnDataObj.cr_response.details) 
      { 
       var id_response = form.fields; 
       return Ok(id_response); 
      } 

但它拋出錯誤，如

<Error> 
<Message>An error has occurred.</Message> 
<ExceptionMessage> 
The 'ObjectContent`1' type failed to serialize the response body for content 
type 'application/xml; charset=utf-8'. 
</ExceptionMessage> 

System.InvalidOperationException

Answer 1

返回從您需要填寫您的陣列外返回它foreach循環網絡API陣列：

var list = new List<string>(); 
foreach (...){ 
    var name = ... 
    list.Add(name); 
} 
return Ok(list.ToArray()); // or just return Ok(list); 

這是豪w ^反序列化JSON到POCO並獲得名稱列表：

[TestMethod] 
public void TestJsonToPocoAndGetNames() 
{ 
    const string Json = @" 
     { 
     ""cr_response"": { 
      ""details"": [{ 
       ""name"": ""Req"", 
       ""fields"": [{ 
         ""value"": ""Prj0\r\nPrj1"", 
         ""name"": ""Project"" 
        }, 
        { 
         ""value"": ""October 13, 2017 14:18"", 
         ""name"": ""Submitted"" 
        }, 
        { 
         ""value"": ""John"", 
         ""name"": ""Rec Name"" 
        } 
       ] 
      }], 
      ""cr_metadata"": {} 
     } 
    } 
    "; 

    var settings = new JsonSerializerSettings 
    { 
     MetadataPropertyHandling = MetadataPropertyHandling.Ignore, 
     DateParseHandling = DateParseHandling.None, 
    }; 
    var response = JsonConvert.DeserializeObject<RootJsonObject>(Json, settings); 

    var names = new List<string>(); 
    foreach (var detail in response.CrResponse.Details) 
    { 
     names.Add(detail.Name); 

     foreach (var field in detail.Fields) 
     { 
      names.Add(field.Name); 
     } 
    } 

    Assert.AreEqual(
     "Req, Project, Submitted, Rec Name", 
     string.Join(", ", names.ToArray())); 
} 

POCO類：

public class RootJsonObject 
{ 
    [JsonProperty("cr_response")] 
    public CrResponse CrResponse { get; set; } 
} 

public class CrResponse 
{ 
    [JsonProperty("cr_metadata")] 
    public CrMetadata CrMetadata { get; set; } 

    [JsonProperty("details")] 
    public Detail[] Details { get; set; } 
} 

public class CrMetadata 
{ 
} 

public class Detail 
{ 
    [JsonProperty("fields")] 
    public Field[] Fields { get; set; } 

    [JsonProperty("name")] 
    public string Name { get; set; } 
} 

public class Field 
{ 
    [JsonProperty("name")] 
    public string Name { get; set; } 

    [JsonProperty("value")] 
    public string Value { get; set; } 
}