FileRead problem

[Удален] 2009.11.13 18:43

I wrote a small script to learn how to use FileRead and FileWrite. FileWrite works OK, becauseI can open the resulting CSV file in NotePad to see the data. The problem is reading the data back into MT4. The script has an Alert in it so I can immediately visualize the data read back in. Only some of the data is read in correctly (see Alert box image following the code). As can be seen in the code, I have numerous FileFlush() commands commented out, as I experimented with number & placement of this command trying to get some output. I seem to be half-way there, but I can only get the first 6 numbers read back in, the last 5 numbers don't read in properly.

Here is the code, following the code is a screen shot of the Alert box and the data from the CSV file.

//+------------------------------------------------------------------+
//| FileFunctionTest.mq4                                             |
//| 										                         |
//+------------------------------------------------------------------+
#include <stdlib.mqh>

#property copyright "Copyright 2009 under Creative Commons BY-SA License by Neil D. Rosenthal"
#property link      "http://creativecommons.org/licenses/by-sa/3.0/"

int             FileHandle;
string		FileName;
int		FileMode;
int		UnitCount = 5;
double		Unit1_Size = 0.1;
double		Unit2_Size = 0.1;
double		Unit3_Size = 0.1;
double		Unit4_Size = 0.2;
double		Unit5_Size = 0.3;
double		TargetPrice1 = 1.47952;
double		TargetPrice2 = 1.47986;
double		TargetPrice3 = 1.48842;
double		TargetPrice4 = 1.48931;
double		TargetPrice5 = 1.49075;
double		PriceTarget1;
double		PriceTarget2;
double		PriceTarget3;
double		PriceTarget4;
double		PriceTarget5;
int             CountUnit;
double          UnitSize1;
double          UnitSize2;
double          UnitSize3;
double          UnitSize4;
double          UnitSize5;

//----
int start()
{
	//----
	FileName = Symbol() + " Trade Data.csv";
	FileHandle = FileOpen(FileName,FILE_CSV|FILE_WRITE,',');
	if(FileHandle > 0)
	{
		FileWrite(FileHandle,UnitCount);
		FileFlush(FileHandle);
		FileWrite(FileHandle,Unit1_Size,Unit2_Size,Unit3_Size,Unit4_Size,Unit5_Size);
		FileFlush(FileHandle);
		FileWrite(FileHandle,TargetPrice1,TargetPrice2,TargetPrice3,TargetPrice4,TargetPrice5);					
		FileClose(FileHandle);
	} //end if(FileHandle > 0)
	
	
	FileHandle = FileOpen(FileName,FILE_CSV|FILE_READ,',');
	if(FileHandle > 0)
	{
		while(!FileIsEnding(FileHandle))
		{
			CountUnit = FileReadNumber(FileHandle);
			//FileFlush(FileHandle);
			UnitSize1 = FileReadNumber(FileHandle);
			//FileFlush(FileHandle);
			UnitSize2 = FileReadNumber(FileHandle);
			//FileFlush(FileHandle);
			UnitSize3 = FileReadNumber(FileHandle);
			//FileFlush(FileHandle);
			UnitSize4 = FileReadNumber(FileHandle);
			//FileFlush(FileHandle);
			UnitSize5 = FileReadNumber(FileHandle);
			FileFlush(FileHandle);
			PriceTarget1 = FileReadNumber(FileHandle);
			//FileFlush(FileHandle);
			PriceTarget2 = FileReadNumber(FileHandle);
			//FileFlush(FileHandle);
			PriceTarget3 = FileReadNumber(FileHandle);
			//FileFlush(FileHandle);
			PriceTarget4 = FileReadNumber(FileHandle);
			//FileFlush(FileHandle);
			PriceTarget5 = FileReadNumber(FileHandle);
			//FileFlush(FileHandle);			
		} //end while(!FileIsEnding(FileHandle))
		FileClose(FileHandle);
	} //end if(FileHandle > 0)
	
	Alert("CountUnit = " + CountUnit +
	       "\nUnitSize1 = " + UnitSize1 +
	       "\nUnitSize2 = " + UnitSize2 +
	       "\nUnitSize3 = " + UnitSize3 +
	       "\nUnitSize4 = " + UnitSize4 +
	       "\nUnitSize5 = " + UnitSize5 +
	       "\nPriceTarget1 = " + PriceTarget1 +
	       "\nPriceTarget2 = " + PriceTarget2 +
	       "\nPriceTarget3 = " + PriceTarget3 +
	       "\nPriceTarget4 = " + PriceTarget4 +
	       "\nPriceTarget5 = " + PriceTarget5);
	       //
	//----
	return(0);
}

Here is the data from the CSV file:

5
0.1,0.1,0.1,0.2,0.3
1.47952,1.47986,1.48842,1.48931,1.49075

Please help! Thanks!

Alexander 2009.11.13 19:16 #1

Try this:

//+------------------------------------------------------------------+
//| FileFunctionTest.mq4                                             |
//|                          |
//+------------------------------------------------------------------+
#include <stdlib.mqh>

#property copyright "Copyright 2009 under Creative Commons BY-SA License by Neil D. Rosenthal"
#property link      "http://creativecommons.org/licenses/by-sa/3.0/"

int             FileHandle;
string FileName;
int FileMode;
int UnitCount = 5;
double Unit1_Size = 0.1;
double Unit2_Size = 0.1;
double Unit3_Size = 0.1;
double Unit4_Size = 0.2;
double Unit5_Size = 0.3;
double TargetPrice1 = 1.47952;
double TargetPrice2 = 1.47986;
double TargetPrice3 = 1.48842;
double TargetPrice4 = 1.48931;
double TargetPrice5 = 1.49075;
double PriceTarget1;
double PriceTarget2;
double PriceTarget3;
double PriceTarget4;
double PriceTarget5;
int             CountUnit;
double          UnitSize1;
double          UnitSize2;
double          UnitSize3;
double          UnitSize4;
double          UnitSize5;

//----
int start()
{
//----
FileName = Symbol() + " Trade Data.csv";
FileHandle = FileOpen(FileName,FILE_CSV|FILE_WRITE,',');
if(FileHandle > 0)
{
FileWrite(FileHandle,UnitCount);
//FileFlush(FileHandle);
FileWrite(FileHandle,Unit1_Size,Unit2_Size,Unit3_Size,Unit4_Size,Unit5_Size);
//FileFlush(FileHandle);
FileWrite(FileHandle,TargetPrice1,TargetPrice2,TargetPrice3,TargetPrice4,TargetPrice5); 
FileClose(FileHandle);
} //end if(FileHandle > 0)


FileHandle = FileOpen(FileName,FILE_CSV|FILE_READ,',');
if(FileHandle > 0)
{
//while(!FileIsEnding(FileHandle))
//{
CountUnit = FileReadNumber(FileHandle);
//FileFlush(FileHandle);
UnitSize1 = FileReadNumber(FileHandle);
//FileFlush(FileHandle);
UnitSize2 = FileReadNumber(FileHandle);
//FileFlush(FileHandle);
UnitSize3 = FileReadNumber(FileHandle);
//FileFlush(FileHandle);
UnitSize4 = FileReadNumber(FileHandle);
//FileFlush(FileHandle);
UnitSize5 = FileReadNumber(FileHandle);
//FileFlush(FileHandle);
PriceTarget1 = FileReadNumber(FileHandle);
//FileFlush(FileHandle);
PriceTarget2 = FileReadNumber(FileHandle);
//FileFlush(FileHandle);
PriceTarget3 = FileReadNumber(FileHandle);
//FileFlush(FileHandle);
PriceTarget4 = FileReadNumber(FileHandle);
//FileFlush(FileHandle);
PriceTarget5 = FileReadNumber(FileHandle);
//FileFlush(FileHandle); 
//end while(!FileIsEnding(FileHandle))
FileClose(FileHandle);
} //end if(FileHandle > 0)

Alert("CountUnit = " + CountUnit +
       "\nUnitSize1 = " + UnitSize1 +
       "\nUnitSize2 = " + UnitSize2 +
       "\nUnitSize3 = " + UnitSize3 +
       "\nUnitSize4 = " + UnitSize4 +
       "\nUnitSize5 = " + UnitSize5 +
       "\nPriceTarget1 = " + PriceTarget1 +
       "\nPriceTarget2 = " + PriceTarget2 +
       "\nPriceTarget3 = " + PriceTarget3 +
       "\nPriceTarget4 = " + PriceTarget4 +
       "\nPriceTarget5 = " + PriceTarget5);
       //
//----
return(0);
}

[Удален] 2009.11.13 23:09 #2

Roger:

Try this:

Thanks, Roger! That works.

I copied the use of the while loop from an article I found here, so I never even thought to remove it.

Why does it fail with the while loop? It would be good to know to increase my understanding of MQL.

Again, thanks for your help.

Trying to add a Questions from Beginners MQL5 How to delete pending

Alexander 2009.11.13 23:52 #3

You can use the loop, this case you have to check every reading for empty string. But this is a waisting time in your case, you know exactly how many numbers you have in the file.

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