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Easy help: Start and stop reading in the middle of a file

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Join Date: Oct 2008

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ApMignonne ApMignonne is offline

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Easy help: Start and stop reading in the middle of a file

Oct 6th, 2008

I'm trying to make a program that will read names and numbers from a file, but I'm quite inexperienced in C++ in general, and most tutorials and help threads I read tend to make me confused.

So far, I have used a test file with a text like "NameA 01234 NameB 11111 NameC 55555". I want the names in one string and the numbers in another one, which I have managed to do with the code:

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
	ifstream in("test.txt");
	string inName[3], inChar[3];
	for (int i= 0; i<3; i++)
		in >> plant[i].name >> plant[i].charString
	ifstream in("test.txt");
	string inName[3], inChar[3];
	for (int i= 0; i<3; i++)
		in >> plant[i].name >> plant[i].charString

My problem now is that the file I actually want to read from is more complicated, and looks more like:
"LotsOfTextThat;IAmNotInterestedIn; MATRIXNameA 01234 NameB 11111 NameC 55555; MoreTextThatIsOfNoUse".
In other words, I want to start reading after the word "MATRIX" and stop at the character ";". How do I edit my code to make it do that?

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Join Date: Oct 2008

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ApMignonne ApMignonne is offline

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Re: Easy help: Start and stop reading in the middle of a file

Oct 6th, 2008

I just saw that I messed up a bit. The code was supposed to be like this:

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
ifstream in("test.txt");
	string inName[3], inChar[3];
	for (int i= 0; i<3; i++)
		in >> inName[i] >> inChar[i]
ifstream in("test.txt");
	string inName[3], inChar[3];
	for (int i= 0; i<3; i++)
		in >> inName[i] >> inChar[i]

and what I want to do is to start reading after the word "MATRIX" and stop before the character ";"

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Join Date: Mar 2008

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Sky Diploma Sky Diploma is offline

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Re: Easy help: Start and stop reading in the middle of a file

Oct 6th, 2008

And Secondly. Why dont you just search for the word Matrix in Your File?

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
string inName[3],inChar[3];
while(in.eof())
string s;
in>>s;
if(s=="matrix")
{
	for (int i= 0; i<3; i++)
{
		in >> inName[i] >> inChar[i];
}
break;
}
else 
//Do nothing 
}
string inName[3],inChar[3];
while(in.eof())
string s;
in>>s;
if(s=="matrix")
{
	for (int i= 0; i<3; i++)
{
		in >> inName[i] >> inChar[i];
}
break;
}
else 
//Do nothing 
}

That way You will read the next words into strings

Last edited by Sky Diploma; Oct 6th, 2008 at 7:22 am.

1. Please Mark Your Thread as Solved After Getting Your Answers.
2. Please Use CODE TAGS .

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Join Date: Oct 2008

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ApMignonne ApMignonne is offline

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Re: Easy help: Start and stop reading in the middle of a file

Oct 6th, 2008

Well, that's just about the help I wanted

As I said, my programming skills are not too great. After a while, I figured out that you must have meant "while(!in.eof())", and now my program works perfectly fine.

Thanks!