//+——————————————————————+
//| Demo_FileReadStruct.mq4 |
//| Copyright 2014, MetaQuotes Software Corp. |
//| https://www.mql5.com |
//+——————————————————————+
#property copyright “Copyright 2014, MetaQuotes Software Corp.”
#property link “https://www.mql5.com”
#property version “1.00”
#property indicator_separate_window
#property indicator_buffers 4
//—- plot Label1
#property indicator_label1 “Open”
#property indicator_type1 DRAW_LINE
#property indicator_color1 clrBlue
#property indicator_style1 STYLE_SOLID
#property indicator_width1 1
#property indicator_label1 “High”
#property indicator_type2 DRAW_LINE
#property indicator_color2 clrGreen
#property indicator_style2 STYLE_SOLID
#property indicator_width2 1
#property indicator_label1 “Low”
#property indicator_type3 DRAW_LINE
#property indicator_color3 clrOrange
#property indicator_style3 STYLE_SOLID
#property indicator_width3 1
#property indicator_label1 “Close”
#property indicator_type4 DRAW_LINE
#property indicator_color4 clrRed
#property indicator_style4 STYLE_SOLID
#property indicator_width4 1
#property indicator_separate_window
//— parameters for receiving data
input string InpFileName=“EURUSD.txt”; // file name
input string InpDirectoryName=“Data”; // directory name
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//| Structure for storing candlestick data |
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struct candlesticks
{
double open; // open price
double close; // close price
double high; // high price
double low; // low price
datetime date; // date
};
//— indicator buffers
double open_buff[];
double close_buff[];
double high_buff[];
double low_buff[];
//— global variables
candlesticks cand_buff[];
int size=0;
int ind=0;
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//| Custom indicator initialization function |
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int OnInit()
{
int default_size=100;
ArrayResize(cand_buff,default_size);
//— open the file
ResetLastError();
int file_handle=FileOpen(InpDirectoryName+“//”+InpFileName,FILE_READ|FILE_BIN|FILE_COMMON);
if(file_handle!=INVALID_HANDLE)
{
PrintFormat(“%s file is available for reading”,InpFileName);
PrintFormat(“File path: %s\\Files\\”,TerminalInfoString(TERMINAL_COMMONDATA_PATH));
//— read data from the file
while(!FileIsEnding(file_handle))
{
//— write data to the array
uint bytesread=FileReadStruct(file_handle,cand_buff[size]);
//— check data read
if (bytesread!=sizeof(candlesticks))
{
PrintFormat(“Error reading data. Error code=%d”,GetLastError());
//— close the file
FileClose(file_handle);
return(INIT_FAILED);
}
else
{
size++;
//— check if the array is overflown
if(size==default_size)
{
//— increase the array size
default_size+=100;
ArrayResize(cand_buff,default_size);
}
}
}
//— close the file
FileClose(file_handle);
PrintFormat(“Data is read, %s file is closed”,InpFileName);
}
else
{
PrintFormat(“Failed to open %s file, Error code = %d”,InpFileName,GetLastError());
return(INIT_FAILED);
}
//— indicator buffers mapping
SetIndexBuffer(0,open_buff,INDICATOR_DATA);
SetIndexBuffer(1,high_buff,INDICATOR_DATA);
SetIndexBuffer(2,low_buff,INDICATOR_DATA);
SetIndexBuffer(3,close_buff,INDICATOR_DATA);
//— empty value
PlotIndexSetDouble(0,PLOT_EMPTY_VALUE,0);
//—
return(INIT_SUCCEEDED);
}
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//| Custom indicator iteration function |
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int OnCalculate(const int rates_total,
const int prev_calculated,
const datetime &time[],
const double &open[],
const double &high[],
const double &low[],
const double &close[],
const long &tick_volume[],
const long &volume[],
const int &spread[])
{
ArraySetAsSeries(time,false);
//— the loop for the candlesticks that have not been handled yet
for(int i=prev_calculated;i<rates_total;i++)
{
//— 0 by default
open_buff[i]=0;
close_buff[i]=0;
high_buff[i]=0;
low_buff[i]=0;
//— check if any data is still present
if(ind<size)
{
for(int j=ind;j<size;j++)
{
//— if dates coincide, the value from the file is used
if(time[i]==cand_buff[j].date)
{
open_buff[i]=cand_buff[j].open;
close_buff[i]=cand_buff[j].close;
high_buff[i]=cand_buff[j].high;
low_buff[i]=cand_buff[j].low;
//— increase the counter
ind=j+1;
break;
}
}
}
}
//— return value of prev_calculated for next call
return(rates_total);
} |