Can an Enum have its own method in MQL4/MQL5. Can i store string in an Enum as a value?

Question

I am trying to write a code where i would like to use ENUM as a class and call some method on it.. For example toString(). Or can i store a string value in an Enum in Mql4/Mql5 language?

Answer 1

No an enum cannot have methods. You can, however, use polymorphic behavior to mimic this desired attribute.

#property strict
#property script_show_inputs
#include <Object.mqh>
//+------------------------------------------------------------------+
enum ENUM_STRAT {STRAT1, STRAT2};
//+------------------------------------------------------------------+
input ENUM_STRAT  inpStrategy=STRAT1;
//+------------------------------------------------------------------+
class StrategyBase : public CObject
{
   public: virtual string toString()=0;  
};
//+------------------------------------------------------------------+
class Strategy1 : public StrategyBase
{
   public: virtual string toString() override { return "Strategy #1"; }
};
//+------------------------------------------------------------------+
class Strategy2 : public StrategyBase
{
   public: virtual string toString() override { return "Strategy #2"; }
};
//+------------------------------------------------------------------+
StrategyBase* initStrategy()
{
   switch(inpStrategy)
   {
      case STRAT1:
         return new Strategy1();
      default:
         return new Strategy2();
   }
}
//+------------------------------------------------------------------+
//| Script program start function                                    |
//+------------------------------------------------------------------+
void OnStart()
{
   StrategyBase *strategy = initStrategy();
   printf("The result of the toString() method is %s", strategy.toString());
   delete strategy;
}