1.21

Changed how the cBot reacts to a zero lot size value reported by the broker. It now uses a fallback value set via parameters.

Author: aamoraru

PositionSizer/PositionSizer/Model/Main/Model.cs

@@ -9,6 +9,7 @@ namespace cAlgo.Robots;
 
 public interface IModelResources
 {
+    double InputFallbackLotSize { get; }
     bool InputCalculateUnadjustedPositionSize { get; }
     bool InputSurpassBrokerMaxPositionSizeWithMultipleTrades { get; }
     //--
@@ -29,6 +30,7 @@ public partial class Model : IModel
 
     private IModelResources _resources;
 
+    private double InputFallbackLotSize => _resources.InputFallbackLotSize;
     private bool InputCalculateUnadjustedPositionSize => _resources.InputCalculateUnadjustedPositionSize;
     private bool InputSurpassBrokerMaxPositionSizeWithMultipleTrades => _resources.InputSurpassBrokerMaxPositionSizeWithMultipleTrades;
     private IAccount Account => _resources.Account;
@@ -257,7 +259,8 @@ public double StandardCommission()
 
         if (Symbol.CommissionType == SymbolCommissionType.UsdPerMillionUsdVolume)
         {
-            var lotSizeOfBaseAssetInAccountCurrency = baseAsset.Convert(accountAsset, Symbol.LotSize);
+            var lotSize = Symbol.LotSize == 0 ? InputFallbackLotSize : Symbol.LotSize;
+            var lotSizeOfBaseAssetInAccountCurrency = baseAsset.Convert(accountAsset, lotSize);
             var commissionPerLotInAccountCurrency = Symbol.Commission / 1_000_000.0 * lotSizeOfBaseAssetInAccountCurrency;
 
             return commissionPerLotInAccountCurrency;

PositionSizer/PositionSizer/Model/TradeSizeMethods.cs

@@ -1,3 +1,4 @@
+using System;
 using System.Linq;
 using cAlgo.API;
 using cAlgo.API.Internals;
@@ -124,6 +125,8 @@ private double CommissionPerUnitVolume()
     {
         // round-trip commission per unit volume in account currency
         // uses StandardCommission() per lot, then divides by lot size and doubles (entry + exit)
-        return 2.0 * StandardCommission() / Symbol.LotSize;
+        return Symbol.LotSize == 0 
+            ? 2.0 * StandardCommission() / InputFallbackLotSize
+            : 2.0 * StandardCommission() / Symbol.LotSize;
     }
 }

PositionSizer/PositionSizer/Parameters.cs

@@ -492,6 +492,9 @@ public partial class PositionSizer
 
     [Parameter("Keep Lines When Robot Is Stopped", DefaultValue = false, Group = "Miscellaneous")]
     public bool InputKeepLinesWhenRobotIsStopped { get; set; }
+
+    [Parameter("Fallback Lot Size", DefaultValue = 1, MinValue = 0.01, Step = 0.01, Group = "Miscellaneous")]
+    public double InputFallbackLotSize { get; set; }
 
     #endregion
 

PositionSizer/PositionSizer/PositionSizer.cs

@@ -4,7 +4,7 @@
 //   WARNING: No warranty. This EA is offered "as is". Use at your own risk.
 //   Note: Pressing Shift+T will open a trade.
 //   
-//   Version 1.20
+//   Version 1.21
 //   Copyright 2024-2025, EarnForex.com
 //   https://www.earnforex.com/ctrader-robots/cTrader-Position-Sizer/
 // -------------------------------------------------------------------------------
@@ -34,7 +34,7 @@ public partial class PositionSizer : Robot,
     public event EventHandler TimerEvent;
     public event EventHandler StopEvent;
     public IModel Model { get; set; }
-    public const string Version = "v1.20";
+    public const string Version = "v1.21";
     public CustomStyle CustomStyle { get; private set; }
     public BreakEven BreakEven { get; private set; }
     public TrailingStop TrailingStop { get; private set; }
@@ -58,9 +58,8 @@ protected override void OnStart()
     {
         if (Symbol.LotSize == 0)
         {
-            var msgText = "This symbol reports a lot size of zero, which prevents the bot from operating correctly. Please select a symbol with a non-zero lot size or update the symbol's contract size and restart the bot.";
+            var msgText = $"This symbol reports zero lot size. Using the Fallback Lot Size value {InputFallbackLotSize}. Commission and swap calculation may be incorrect.";
             MessageBox.Show(msgText, "Warning!", MessageBoxButton.OK, MessageBoxImage.Warning);
-            Stop();
         }
 
         //System.Diagnostics.Debugger.Launch();

PositionSizer/PositionSizer/View/Pages/SwapsView.cs

@@ -11,6 +11,7 @@ public interface ISwapsViewResources
     IAccount Account { get; }
     CustomStyle CustomStyle { get; }
     bool InputDarkMode { get; }
+    double InputFallbackLotSize { get; }
 }
 
 public class SwapsView : Button, ISwapsViewResources
@@ -32,6 +33,10 @@ public SwapsView(ISwapsViewResources resources)
         _grid.AddRows(9);
         Content = _grid;
         Width = 400;
+        
+        var lotSizeValue = Symbol.LotSize == 0 
+            ? InputFallbackLotSize
+            : Symbol.LotSize;
 
         var row = 0;
 
@@ -87,11 +92,11 @@ public SwapsView(ISwapsViewResources resources)
 
         _grid.AddChild(dailyTextBlock, row, 0);
 
-        var longDailyTextBox = MakeTextBox((Symbol.SwapLong * Symbol.PipValue * Symbol.LotSize).ToString("F"));
+        var longDailyTextBox = MakeTextBox((Symbol.SwapLong * Symbol.PipValue * lotSizeValue).ToString("F"));
 
         _grid.AddChild(longDailyTextBox, row, 1);
 
-        var shortDailyTextBox = MakeTextBox((Symbol.SwapShort * Symbol.PipValue * Symbol.LotSize).ToString("F"));
+        var shortDailyTextBox = MakeTextBox((Symbol.SwapShort * Symbol.PipValue * lotSizeValue).ToString("F"));
 
         _grid.AddChild(shortDailyTextBox, row, 2);
 
@@ -120,11 +125,11 @@ public SwapsView(ISwapsViewResources resources)
 
         _grid.AddChild(yearlyTextBlock, row, 0);
 
-        var longYearlyTextBox = MakeTextBox($"{Symbol.SwapLong * Symbol.PipValue * Symbol.LotSize * 360:F2}");
+        var longYearlyTextBox = MakeTextBox($"{Symbol.SwapLong * Symbol.PipValue * lotSizeValue * 360:F2}");
 
         _grid.AddChild(longYearlyTextBox, row, 1);
 
-        var shortYearlyTextBox = MakeTextBox($"{Symbol.SwapShort * Symbol.PipValue * Symbol.LotSize * 360:F2}");
+        var shortYearlyTextBox = MakeTextBox($"{Symbol.SwapShort * Symbol.PipValue * lotSizeValue * 360:F2}");
 
         _grid.AddChild(shortYearlyTextBox, row, 2);
 
@@ -248,4 +253,5 @@ private XTextBoxDouble MakeTextBox(double value)
     public IAccount Account => _resources.Account;
     public CustomStyle CustomStyle => _resources.CustomStyle;
     public bool InputDarkMode => _resources.InputDarkMode;
+    public double InputFallbackLotSize => _resources.InputFallbackLotSize;
 }

PositionSizer/PositionSizer/View/SetupWindowView.cs

@@ -79,6 +79,7 @@ public interface ISetupWindowResources
     Color InputLongButtonColor { get; }
     Color InputShortButtonColor { get; }
     Color InputTradeButtonColor { get; }
+    double InputFallbackLotSize { get; }
 }
 
 public enum WindowActive
@@ -696,6 +697,7 @@ public void Stop()
 
     public LocalStorage LocalStorage => _resources.LocalStorage;
     public string CleanBrokerName => _resources.CleanBrokerName;
+    public double InputFallbackLotSize => _resources.InputFallbackLotSize;
 
     private void OnHideShowClickEvent()
     {