AX / D365FO – Deserialize JSON string in D365FO using X++

Create contract class for both outer and inner node.
FormJsonSerializer::deserializeObject method

Sample JSON : “data”: [
{
“ID Nation”: “01000US”,
“Nation”: “United States”,
“ID Year”: 2020,
“Year”: “2020”,
“Population”: 326569308,
“Slug Nation”: “united-states”
},
{
“ID Nation”: “01000US”,
“Nation”: “United States”,
“ID Year”: 2019,
“Year”: “2019”,
“Population”: 324697795,
“Slug Nation”: “united-states”
}]

Step 1: Create contract class 1 to hold all the values of data node.

[DataContract]
internal final class TestJSONContract
{
String50 parmNationId, parmNation,parmYearId,parmYear,parmPopulation,parmSlugNation;[DataMemberAttribute('ID Nation')]
public String50 parmNationId(String50 _parmNationId = parmNationId)
{
    parmNationId = _parmNationId;
    return parmNationId;
}

[DataMemberAttribute('Nation')]
public String50 parmNation(String50 _parmNation = parmNation)
{
    parmNation = _parmNation;
    return parmNation;
}

[DataMemberAttribute('ID Year')]
public String50 parmYearId(String50 _parmYearId = parmYearId)
{

    parmYearId = _parmYearId;
    return parmYearId;
}

[DataMemberAttribute('Year')]
public String50 parmYear(String50 _parmYear = parmYear)
{
    parmYear = _parmYear;
    return parmYear;
}

[DataMemberAttribute('Population')]
public String50 parmPopulation(String50 _parmPopulation = parmPopulation)
{
    parmPopulation = _parmPopulation;
    return parmPopulation;
}

[DataMemberAttribute('Slug Nation')]
public String50 parmSlugNation(String50 _parmSlugNation = parmSlugNation)
{
    parmSlugNation = _parmSlugNation;
    return parmSlugNation;
}
}

Step 2: Create contract class for outer node.

if there is more than one outer node then you need to create your class according to your JOSN. ex

[DataContract]
internal final class TestJSONDataContract
{
List parmData;
[DataMemberAttribute('data'),DataCollectionAttribute(Types::class, classStr(TestJSONContract))]
public List parmData(List _parmData = parmData)
{
    parmData = _parmData;
    return parmData;
}
}

Step 3: Create runnable class to call your API and get the result.

   internal final class TestConsumeAPITest
{
public static void main(Args _args)
{
System.Net.HttpWebRequest webRequest;
System.Net.HttpWebResponse webresponse;
System.Exception ex;
System.IO.Stream responseStream;
System.IO.StreamReader reader;
str output;
ListEnumerator listEnumerator;
try
    {
      new InteropPermission(InteropKind::ClrInterop).assert();

      webRequest = System.Net.WebRequest::Create("##########"); //your API URL goes here.   

      webRequest.Method = "GET";
      webRequest.ContentType = "application/json";
      webresponse = webRequest.GetResponse();
      responseStream = webresponse.GetResponseStream();
      reader = new System.IO.StreamReader(responseStream);

      output = reader.ReadToEnd();

      TestJSONDataContract TestJSONDataContract = FormJsonSerializer::deserializeObject(classNum(TestJSONDataContract),output);

      List listData = new List(Types::Class);

      listData          = TestJSONDataContract.parmData();
      listEnumerator    = listData.getEnumerator();

      while (listEnumerator.moveNext())
      {
        TestJSONContract jsonDataContract = listEnumerator.current();

        info(strFmt("Nation id %1 : %2 = %3",jsonDataCOntract.parmNationId(), jsonDataContract.parmNation(), jsonDataContract.parmPopulation()));
      }

    }
    catch
    {
      ex = CLRInterop::getLastException().GetBaseException();
      error(ex.get_Message());
    }

  }

}

Finally execute your runnable class to test the API and JSON format.