how to use Ref Parameter in REST Web API

Question

Hi

How to pass ref parameter through HTTP Get method in Rest Web api and get the result in postman.

How to return the no of records as well as Dataset in Rest Web api.plz help.

public JsonResult<DataSet> GetRecords(string Code,ref int noofrecords
{
    DataSet ds = new DataSet();
    try
    {
        SqlDataAdapter da = new SqlDataAdapter("GetRecords", con);
        con.Open();
        da.SelectCommand.CommandType = CommandType.StoredProcedure;
        SqlParameter ret = new SqlParameter();
        ret.Direction = ParameterDirection.ReturnValue;
        da.SelectCommand.Parameters.Add("@Code", SqlDbType.VarChar, 20).Value = Code;
        da.SelectCommand.Parameters.Add(ret);
        da.Fill(ds, "StudentList");
        noofrecords = (int)ret.Value;
    } 
    catch (Exception)  {   
    }
    return Json(ds);
}

Sachin Singh · Answer

what do you think a rest API should look like the first HTTP is stateless, and second, everything is a resource, your method definition is violating these principles. second, it is completely not possible to call a method having ref/out keyword by an URL, so again the violation of REST principle. Moreover, ref and out are not designed for Action Methods as they can't be called using query string or routed data. So, Your Method is wrong. You can simply use public IHttpActionResult GetRecords(string Code) { DataSet ds = new DataSet(); try { SqlDataAdapter da = new SqlDataAdapter( "GetRecords" , con); con.Open(); da.SelectCommand.CommandType = CommandType.StoredProcedure; SqlParameter ret = new SqlParameter(); ret.Direction = ParameterDirection.ReturnValue; da.SelectCommand.Parameters.Add( "@Code" , SqlDbType.VarChar, 20).Value = Code; da.SelectCommand.Parameters.Add(ret); da.Fill(ds, "StudentList" ); int noofrecords = ( int )ret.Value; } catch (Exception) { } return Ok( new KeyValuePair int ,DataSet>(noofrecords ,ds)); }

Kiran Mohanty · Answer

Hi, You can use Tuple to return multiple paramters . Tuple int , DataSet> data = new Tuple int , DataSet,>( noofrecords, ds ); return Json(data);