WCF Service and Windows Application Client. why client receives null - winforms

Question

I have mapped the service with a linq to Sql classes and I am using wcf library for vs 2019 and in client a win form app.
I am trying sending the class created for linq to sql the next way
public List<Trades> GetAllTradings()
{
context = new DCStockTradingDataContext();
List<Trades> tradings = (from t in context.Trades
select t).ToList();
return tradings;
}
and the client
private void btnRun_Click(object sender, EventArgs e)
{
Service1Client client = new Service1Client();
var trades = client.GetAllTradings();
dgViewStocks.DataSource = trades;
//string ret = client.GetData("Hello");
//Console.WriteLine(ret);
}
I din´t know what is happening and I don´t know what is wrong
The service
and the client receives all null
I would appreciate any help about this and thank you in advance

Answer 1

If you get null response in WCF client, some advices:
try to call the service in SoapUi with Validation of request and response turned on. It may be useful in detecting problems.
debug Reference.cs file to see more closely what is going on
use MessageInspector to see what is received in AfterReceiveReply method
examine namespaces attentively, response often cannot be deserialized because of the difference in namespaces that are in Reference.cs and in real service

Answer 2

Thanks for your response and everything if this I did.
I found how I have to work with linq to sql classes and wcf. We need to take into account that you need to convert the List of linq classes to List<string. What I did
enter code here
public List<string[]> GetAllStocks()
{
context = new DCStockTradingDataContext();
System.Data.Linq.Table<Stocks> stocks = context.GetTable<Stocks>();
var allStock = (from st in stocks
select new
{
stockId = (string) st.CodeID,
currency = (char) st.Currency,
stName = st.Name,
price = (decimal) st.Price,
volument = (decimal) st.Volumen
}).ToList();
List<string[]> listRetruned = new List<string[]>();
foreach (var tr in allStock)
{
string[] t = new string[5];
t[0] = tr.stockId;
t[1] = tr.currency.ToString();
t[2] = tr.stName;
t[3] = tr.price.ToString();
t[4] = tr.volument.ToString();
listRetruned.Add(t);
}
return listRetruned;
}
and the client
I have created a model class with the expected data
public class TradingModel
{
public string TradeID { get; set; }
public string StockId { get; set; }
public decimal Bid { get; set; }
public int BidQty { get; set; }
public decimal Ask{get;set;}
public int AskQty { get; set; }
public decimal Last { get; set; }
}
and finally the method
List<TradingModel> models = new List<TradingModel>();
for(int i = 0; i < trades.Length; i++)
{
TradingModel model = new TradingModel()
{
Ask = Convert.ToDecimal(trades[i][0]),
Bid = Convert.ToDecimal(trades[i][1]),
BidQty = Convert.ToInt32(trades[i][2]),
AskQty = Convert.ToInt32(trades[i][3]),
Last = Convert.ToDecimal(trades[i][4]),
StockId = trades[i][5],
TradeID = trades[i][6],
};
models.Add(model);
}
dgViewStocks.DataSource = models;
I am not sure if this is the best way to jump to next step, but it worked for me. If someone is looking for this info as I did, wasting several days chasing the solution, I leave what I did.
There is off course changing the service and generate the proxy again