//+——————————————————————+
//| Expert Advisor |
//| Test of SymbolInfoDouble() |
//+——————————————————————+
#include <Trade\Trade.mqh> // Library for trade functions

//+——————————————————————+
//| Expert Advisor Start function |
//+——————————————————————+
void OnTick()
{
// Define the symbol name for the current chart
string symbol = _Symbol;

// Retrieve symbol information
double maxLotSize = SymbolInfoDouble(symbol,SYMBOL_VOLUME_MAX); // Retrieve max lot size
double minLotSize = SymbolInfoDouble(symbol, SYMBOL_VOLUME_MIN); // Retrieve minimum lot size
double pointsize = SymbolInfoDouble(symbol, SYMBOL_POINT);

// Output lot size
Print(“Max lot size: “, maxLotSize);
Print(“Min lot size: “, minLotSize);
Print(“Point Size: “, pointsize);

// Further processing of the result
// …

// Making trading decisions
// …
}

 

To create an Expert Advisor that utilizes the SymbolInfoDouble() function, you first need to incorporate the required libraries and functions into your code. Ensure you use the appropriate function variants when programming the Expert Advisor.

To use the SymbolInfoDouble() function, you must specify the desired trading symbol. This can either be the current chart or another trading symbol. You can specify the symbol name as a string, e.g., “EURUSD” or “GBPUSD”.

Once you’ve specified the trading symbol, you can invoke the SymbolInfoDouble() function to retrieve information about the symbol. The function returns a double value that contains various details about the symbol. Examples include the point value, minimum lot size, or other trading-specific information.

To utilize the returned data, you can assign the double value to a variable and further process it in your Expert Advisor. For instance, you might use the point value to make trading decisions or verify the minimum lot size before opening a position.

It’s essential to know that the SymbolInfoDouble() function only provides information about the specified trading symbol. If you wish to fetch details about other symbols, you must call the function again with the relevant symbol name.

To test your Expert Advisor, you can deploy the SymbolInfoDouble() function in a test environment to ensure the returned data is accurate. For example, you might want to check the spread value to ascertain it matches expected values.

Overall, the SymbolInfoDouble() function is a valuable tool for fetching details about trading symbols and utilizing them in your Expert Advisor. By leveraging this function, you can tailor your Expert Advisor to a trading symbol’s specific attributes and make informed trading decisions.