Symbol Properties

To obtain the current market information there are several functions: SymbolInfoInteger(), SymbolInfoDouble() and SymbolInfoString(). The first parameter is the symbol name, the values of the second function parameter can be one of the identifiers of ENUM_SYMBOL_INFO_INTEGER, ENUM_SYMBOL_INFO_DOUBLE and ENUM_SYMBOL_INFO_STRING.

For function SymbolInfoInteger()

ENUM_SYMBOL_INFO_INTEGER

For function SymbolInfoDouble()

ENUM_SYMBOL_INFO_DOUBLE

For function SymbolInfoString()

ENUM_SYMBOL_INFO_STRING

A symbol price chart can be based on Bid or Last prices. The price selected for symbol charts also affects the generation and display of bars in the terminal. Possible values of the SYMBOL_CHART_MODE property are described in ENUM_SYMBOL_CHART_MODE

ENUM_SYMBOL_CHART_MODE

For each symbol several expiration modes of pending orders can be specified. A flag is matched to each mode. Flags can be combined using the operation of logicalOR (|), for example, SYMBOL_EXPIRATION_GTC|SYMBOL_EXPIRATION_SPECIFIED. In order to check whether a certain mode is allowed for the symbol, the result of the logical AND (&) should be compared to the mode flag.

If flag SYMBOL_EXPIRATION_SPECIFIED is specified for a symbol, then while sending a pending order, you may specify the moment this pending order is valid till.

Example:

//+------------------------------------------------------------------+
//| Checks if the specified expiration mode is allowed               |
//+------------------------------------------------------------------+
bool IsExpirationTypeAllowed(string symbol,int exp_type)
  {
//--- Obtain the value of the property that describes allowed expiration modes
   int expiration=(int)SymbolInfoInteger(symbol,SYMBOL_EXPIRATION_MODE);
//--- Return true, if mode exp_type is allowed
   return((expiration&exp_type)==exp_type);
  }

If the SYMBOL_EXPIRATION_MODE property is set to SYMBOL_EXPIRATION_GTC (good till canceled), the expiration of pending orders, as well as of Stop Loss/Take Profit orders should be additionally set using the ENUM_SYMBOL_ORDER_GTC_MODE enumeration.

ENUM_SYMBOL_ORDER_GTC_MODE

When sending an order, we can specify the filling policy of a volume set in the order. The possible volume-based order execution options for each symbol are specified in the table. It is possible to set several modes for each instrument via a combination of flags. The combination of flags is expressed by the logical OR (|) operation, for example SYMBOL_FILLING_FOK|SYMBOL_FILLING_IOC. To check if a specific mode is allowed for an instrument, compare the logical AND (&) result with the mode flag - example.

When sending a trade request using the OrderSend() function, the necessary volume execution policy can be set in the type_filling field, namely in the special MqlTradeRequest structure. The values from the ENUM_ORDER_TYPE_FILLING enumeration are available. If no filling type is specified, ORDER_FILLING_RETURN is automatically set in the trade request. The ORDER_FILLING_RETURN filling type is enabled in any execution mode except for “Market execution” (SYMBOL_TRADE_EXECUTION_MARKET).

While sending a trade request for execution at the current time (time in force), we should keep in mind that financial markets provide no guarantee that the entire requested volume is available for a certain financial instrument at the desired price. Therefore, trading operations in real time are regulated using the price and volume execution modes. The modes, or execution policies, define the rules for cases when the price has changed or the requested volume cannot be completely fulfilled at the moment.

Before sending an order with the current execution time, for the correct setting of the ORDER_TYPE_FILLING value (volume execution type), you can use the SymbolInfoInteger() function with each financial instrument to get the SYMBOL_FILLING_MODE property value, which shows volume execution types allowed for the symbol as a combination of flags. The ORDER_FILLING_RETURN filling type is enabled at all times except for the “Market execution” mode (SYMBOL_TRADE_EXECUTION_MARKET).

The use of filling types depending on the execution mode can be shown as the following table:

In case of pending orders, the ORDER_FILLING_RETURN filling type should be used regardless of an execution type (SYMBOL_TRADE_EXEMODE), since such orders are not meant for execution at the time of sending. When using pending orders, a trader agrees in advance that, when conditions for a deal on this order are met, the broker will use the filling type supported by the exchange.

Example:

//+------------------------------------------------------------------+
//| check if a given filling mode is allowed                         |
//+------------------------------------------------------------------+
bool IsFillingTypeAllowed(string symbol,int fill_type)
  {
//--- get the value of the property describing the filling mode
   int filling=(int)SymbolInfoInteger(symbol,SYMBOL_FILLING_MODE);
//--- return 'true' if the fill_type mode is allowed
   return((filling&fill_type)==fill_type);
  }

When sending a trade request using OrderSend() function, an order type from ENUM_ORDER_TYPE enumeration should be specified for some operations. Not all types of orders may be allowed for a specific symbol. SYMBOL_ORDER_MODE property describes the flags of the allowed order types.

Example:

//+------------------------------------------------------------------+
//| The function prints out order types allowed for a symbol         |
//+------------------------------------------------------------------+
void Check_SYMBOL_ORDER_MODE(string symbol)
  {
//--- receive the value of the property describing allowed order types
   int symbol_order_mode=(int)SymbolInfoInteger(symbol,SYMBOL_ORDER_MODE);
//--- check for market orders (Market Execution)
   if((SYMBOL_ORDER_MARKET&symbol_order_mode)==SYMBOL_ORDER_MARKET)
      Print(symbol+": Market orders are allowed (Buy and Sell)");
//--- check for Limit orders
   if((SYMBOL_ORDER_LIMIT&symbol_order_mode)==SYMBOL_ORDER_LIMIT)
      Print(symbol+": Buy Limit and Sell Limit orders are allowed");
//--- check for Stop orders
   if((SYMBOL_ORDER_STOP&symbol_order_mode)==SYMBOL_ORDER_STOP)
      Print(symbol+": Buy Stop and Sell Stop orders are allowed");
//--- check for Stop Limit orders
   if((SYMBOL_ORDER_STOP_LIMIT&symbol_order_mode)==SYMBOL_ORDER_STOP_LIMIT)
      Print(symbol+": Buy Stop Limit and Sell Stop Limit orders are allowed");
//--- check if placing a Stop Loss orders is allowed
   if((SYMBOL_ORDER_SL&symbol_order_mode)==SYMBOL_ORDER_SL)
      Print(symbol+": Stop Loss orders are allowed");
//--- check if placing a Take Profit orders is allowed
   if((SYMBOL_ORDER_TP&symbol_order_mode)==SYMBOL_ORDER_TP)
      Print(symbol+": Take Profit orders are allowed");
//--- check if closing a position by an opposite one is allowed
   if((SYMBOL_ORDER_TP&symbol_order_mode)==SYMBOL_ORDER_CLOSEBY)
      Print(symbol+": Close by allowed");
//---
  }

The ENUM_SYMBOL_CALC_MODE enumeration is used for obtaining information about how the margin requirements for a symbol are calculated.

ENUM_SYMBOL_CALC_MODE

There are several symbol trading modes. Information about trading modes of a certain symbol is reflected in the values of enumeration ENUM_SYMBOL_TRADE_MODE.

ENUM_SYMBOL_TRADE_MODE

Possible deal execution modes for a certain symbol are defined in enumeration ENUM_SYMBOL_TRADE_EXECUTION.

ENUM_SYMBOL_TRADE_EXECUTION

Methods of swap calculation at position transfer are specified in enumeration ENUM_SYMBOL_SWAP_MODE. The method of swap calculation determines the units of measure of the SYMBOL_SWAP_LONG and SYMBOL_SWAP_SHORT parameters. For example, if swaps are charged in the client deposit currency, then the values of those parameters are specified as an amount of money in the client deposit currency.

ENUM_SYMBOL_SWAP_MODE

Values of the ENUM_DAY_OF_WEEK enumeration are used for specifying days of week.

ENUM_DAY_OF_WEEK

An option is a contract, which gives the right, but not the obligation, to buy or sell an underlying asset (goods, stocks, futures, etc.) at a specified price on or before a specific date. The following enumerations describe option properties, including the option type and the right arising from it.

ENUM_SYMBOL_OPTION_RIGHT

ENUM_SYMBOL_OPTION_MODE

Financial instruments are categorized by sectors of the economy. An economic sector is a part of economic activity which has specific characteristics, economic goals, functions and behavior, which allow separating this sector from other parts of the economy. ENUM_SYMBOL_SECTOR lists the economic sectors which a trading instruments can belong to.

ENUM_SYMBOL_SECTOR

Each financial instrument can be assigned to a specific type of industry or economy branch. An industry is a branch of an economy that produces a closely related set of raw materials, goods, or services. ENUM_SYMBOL_INDUSTRY lists industries which a trading instrument can belong to.

ENUM_SYMBOL_INDUSTRY