| //+——————————————————————+//|                                         Demo_FileWriteStruct.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”
 //— show the window of input parameters when launching the script
 #property script_show_inputs
 #property strict
 //— parameters for receiving data from the terminal
 input string          InpSymbolName=“EURUSD”;           // currency pair
 input ENUM_TIMEFRAMES InpSymbolPeriod=PERIOD_H1;        // time frame
 input datetime        InpDateStart=D’2013.01.01 00:00′; // data copying start date
 //— parameters for writing data to the file
 input string          InpFileName=“EURUSD.txt”;         // file name
 input string          InpDirectoryName=“Data”;          // directory name
 //+——————————————————————+
 //| Structure for storing candlestick data                           |
 //+——————————————————————+
 struct candlesticks
 {
 double            open;  // open price
 double            close; // close price
 double            high;  // high price
 double            low;   // low price
 datetime          date;  // date
 };
 //+——————————————————————+
 //| Script program start function                                    |
 //+——————————————————————+
 void OnStart()
 {
 datetime     date_finish=TimeCurrent();
 int          size;
 datetime     time_buff[];
 double       open_buff[];
 double       close_buff[];
 double       high_buff[];
 double       low_buff[];
 candlesticks cand_buff[];
 //— reset the error value
 ResetLastError();
 //— receive the time of the arrival of the bars from the range
 if(CopyTime(InpSymbolName,InpSymbolPeriod,InpDateStart,date_finish,time_buff)==-1)
 {
 PrintFormat(“Failed to copy time values. Error code = %d”,GetLastError());
 return;
 }
 //— receive high prices of the bars from the range
 if(CopyHigh(InpSymbolName,InpSymbolPeriod,InpDateStart,date_finish,high_buff)==-1)
 {
 PrintFormat(“Failed to copy values of high prices. Error code = %d”,GetLastError());
 return;
 }
 //— receive low prices of the bars from the range
 if(CopyLow(InpSymbolName,InpSymbolPeriod,InpDateStart,date_finish,low_buff)==-1)
 {
 PrintFormat(“Failed to copy values of low prices. Error code = %d”,GetLastError());
 return;
 }
 //— receive open prices of the bars from the range
 if(CopyOpen(InpSymbolName,InpSymbolPeriod,InpDateStart,date_finish,open_buff)==-1)
 {
 PrintFormat(“Failed to copy values of open prices. Error code = %d”,GetLastError());
 return;
 }
 //— receive close prices of the bars from the range
 if(CopyClose(InpSymbolName,InpSymbolPeriod,InpDateStart,date_finish,close_buff)==-1)
 {
 PrintFormat(“Failed to copy values of close prices. Error code = %d”,GetLastError());
 return;
 }
 //— define dimension of the arrays
 size=ArraySize(time_buff);
 //— save all data in the structure array
 ArrayResize(cand_buff,size);
 for(int i=0;i<size;i++)
 {
 cand_buff[i].open=open_buff[i];
 cand_buff[i].close=close_buff[i];
 cand_buff[i].high=high_buff[i];
 cand_buff[i].low=low_buff[i];
 cand_buff[i].date=time_buff[i];
 }
 //— open the file for writing the structure array to the file (if the file is absent, it will be created automatically)
 ResetLastError();
 int file_handle=FileOpen(InpDirectoryName+“//”+InpFileName,FILE_READ|FILE_WRITE|FILE_BIN|FILE_COMMON);
 if(file_handle!=INVALID_HANDLE)
 {
 PrintFormat(“%s file is open for writing”,InpFileName);
 PrintFormat(“File path: %s\\Files\\”,TerminalInfoString(TERMINAL_COMMONDATA_PATH));
 //— prepare the counter of the number of bytes
 uint counter=0;
 //— write array values in the loop
 for(int i=0;i<size;i++)
 {
 uint byteswritten=FileWriteStruct(file_handle,cand_buff[i]);
 //— check the number of bytes written
 if(byteswritten!=sizeof(candlesticks))
 {
 PrintFormat(“Error read data. Error code=%d”,GetLastError());
 //— close the file
 FileClose(file_handle);
 return;
 }
 else
 counter+=byteswritten;
 }
 PrintFormat(“%d bytes of information is written to %s file”,InpFileName,counter);
 PrintFormat(“Total number of bytes: %d * %d * %d = %d, %s”,size,5,8,size*5*8,size*5*8==counter ? “Correct” : “Error”);
 //— close the file
 FileClose(file_handle);
 PrintFormat(“Data is written, %s file is closed”,InpFileName);
 }
 else
 PrintFormat(“Failed to open %s file, Error code = %d”,InpFileName,GetLastError());
 }
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