MQL5 ReferenceMarket InfoSymbolName 

SymbolName

Returns the name of a symbol.

string  SymbolName(
   int   pos,          // number in the list
   bool  selected      // true - only symbols in MarketWatch
   );

Parameters

pos

[in] Order number of a symbol.

selected

[in] Request mode. If the value is true, the symbol is taken from the list of symbols selected in MarketWatch. If the value is false, the symbol is taken from the general list.

Return Value

Value of string type with the symbol name.