外汇货币对的交易成本(The trade cost of Forex Currency) Part4

通过比较发现，在美元账户和英镑账户下，计算得到的点差成本与实际交易得到的点差成本完全一致。由于价格的波动，某些货币对输出的点差成本可能与实际点差成本有略微的差别。

3.  测试EA代码

//+------------------------------------------------------------------+
//|                                            EA_TestSpreadCost.mq5 |
//|                                      Copyright 2017, Yupeng Xiao |
//|                                                  shaw_yp@126.com |
//+------------------------------------------------------------------+
#include "SpreadCost.mqh"
#include <Trade\Trade.mqh>
//+------------------------------------------------------------------+
//| Global var                                                       |
//+------------------------------------------------------------------+
const double TestLots = 1.0;
string g_symbols[] = {"EURUSD","CADJPY","EURGBP","XAUEUR","EURHKD"};
int g_totalnum = 5;
int g_spread_output[5]; //output spread
double g_cost_output[5];//putput cost
int g_spread_test[5];   //test spread by trade 
double g_cost_test[5];  //test cost by trade 
CTrade otrade;
CSpreadCost oSpreadCost(TestLots);
int OnInit()
{
   oSpreadCost.GetSymbolsSpreadCost(g_symbols,g_spread_output,g_cost_output);
   TradeSymbols();
   PrintInfo();
   return(INIT_SUCCEEDED);
}
//+------------------------------------------------------------------+
//| Expert deinitialization function                                 |
//+------------------------------------------------------------------+
void OnDeinit(const int reason)
  {
//---
  }
//+------------------------------------------------------------------+
//| Print spread and Trade Cost Info                                 |
//+------------------------------------------------------------------+
void PrintInfo()
{     
   string AccountCurrency = "USD";
   for(int i=0;i<g_totalnum;i++) 
   {
      AccountCurrency = AccountInfoString(ACCOUNT_CURRENCY);
      Print(i+1,". ",g_symbols[i]," OutputSpread is:",g_spread_output[i],", TestSpread is:",g_spread_test[i],
            ", OutputCost is:",DoubleToString(g_cost_output[i],2),"(",AccountCurrency,"), TestCost is:",
            DoubleToString(g_cost_test[i],2),"(",AccountCurrency,")!!"); 
   }
   
   return;
}
//+------------------------------------------------------------------+
//| Trade get test cost                                              |
//+------------------------------------------------------------------+
void TradeSymbols()
{
   MqlTick latest_price;
    
   for(int i = 0; i < g_totalnum; i++)
   {
      otrade.Buy(TestLots,g_symbols[i],latest_price.ask);
      
      PositionSelect(g_symbols[i]);
      g_spread_test[i] = (int)SymbolInfoInteger(g_symbols[i],SYMBOL_SPREAD);
      g_cost_test[i] = MathAbs(PositionGetDouble(POSITION_PROFIT));
      
      otrade.PositionClose(g_symbols[i],g_spread_output[i]*2);
   }
}