How to return data in JSON format from a Webapi . net

Question

I’m making a call inside the API to return consumer data, but I would like to know how to return this data to the client in JSON format.

My controller:

[System.Web.Http.HttpGet]   
public async Task<ActionResult> GetConsumidor()
{
  ConsumidorDAO consumidor = new ConsumidorDAO();
  string dadosConsumidor = consumidor.getDados();

  return (dadosConsumidor);
}

I make a query in the database to bring up some data of a consumer such as name, surname, etc.

public string getDados()
{
  OracleCommand lOracleCommand = lOracleConnection.CreateCommand();
  String query;
  string nome = "";

  try
  {
    query = "select nome " +
      "from crd.cliente " +
      "where cpf_cgc = 'xxxxxxx'" +
      "  and empresa_origem = '367' ";

    lOracleCommand.CommandText = query;
    OracleDataReader reader = lOracleCommand.ExecuteReader();
    while (reader.Read())
    {
      nome = reader["nome"].ToString();
    }
  }
  catch (Exception lException)
  {
    _status += lException.Message + "\n";
    lOracleCommand.Connection.Close();
  }

  return nome;
}

Answer 1

JSON is an object representation in Javascript format (Javascript Object Notation).
As you are returning only one string, this does not fit as an object, objects are formed by zero or more key and value pairs.

If you insist on returning one JSON, can make an object with a property that has its value as a string and serialize it in the return of API, follows an example.

Example:

//outros using
using System.Web.Script.Serialization;


public class ResultadoObjeto
{
    public string Propriedade { get; set; }
}

[System.Web.Http.HttpGet]   
public async Task<string> GetConsumidor()
{
   ConsumidorDAO consumidor = new ConsumidorDAO();
   string dadosConsumidor = consumidor.getDados();

   //aqui gero e preencho o objeto
   var resultadoObjeto = new ResultadoObjeto();
   resultadoObjeto.Propriedade = dadosConsumidor;

   //aqui o transformo em JSON e retorno
   string json = new JavaScriptSerializer().Serialize(resultadoObjeto);
   return (json);

}