Thread: File I/O both ASCII and binary handling in C++

well, here's some quick code to get you started with binary file I/O:

Code:

//use iostream for standard console I/O
#include <iostream>
//use fstream for standard file I/O
#include <fstream>

int main()
{
	//declare a variable to write to the file
	char ch='A';
	
	//open the file for binary reading and writing
	std::fstream file("test.in",std::ios::in|std::ios::out|
		std::ios::trunc|std::ios::binary);
	//write the char to the file (note the cast and sizeof method)
	file.write(reinterpret_cast<char*>(&ch),sizeof(ch));
	//reset the 'read' or 'get' pointer to the beginning of the file
	file.seekg(0,std::ios::beg);
	//read from the file (again note the cast and sizeof)
	file.read(reinterpret_cast<char*>(&ch),sizeof(ch));
	//close the file
	file.close();
	
	//output the character read from the file
	std::cout<<ch<<std::endl;
	//end the program
	return 0;
}

as for text reading and writing, this site has a tutorial on that: http://www.cprogramming.com/tutorial/lesson10.html

it's alot easier to find tutorials on text reading/writing - I didn't even know about binary reading/writing until college...

it enables you to put any data type out to the file, including your own home-baked ones... for example:

Code:

//use iostream for standard console I/O
#include <iostream>
//use fstream for standard file I/O
#include <fstream>
//use cctype for strlen
#include <cctype>

struct myStruct
{
	char*line;
	int letters;
};

int main()
{
	//declare a variable to write to the file
	myStruct A;

	//fill in the struct with some dummy data
	A.line="Hello World";
	A.letters=strlen(A.line);
	
	//open the file for binary reading and writing
	std::fstream file("test.in",std::ios::in|std::ios::out|
		std::ios::trunc|std::ios::binary);
	//write the char to the file (note the cast and sizeof method)
	file.write(reinterpret_cast<char*>(&A),sizeof(A));
	//reset the 'read' or 'get' pointer to the beginning of the file
	file.seekg(0,std::ios::beg);
	//read from the file (again note the cast and sizeof)
	file.read(reinterpret_cast<char*>(&A),sizeof(A));
	//close the file
	file.close();
	
	//output the character read from the file
	std::cout<<A.line<<std::endl<<A.letters<<std::endl;
	//end the program
	return 0;
}

technically every file is binary, but i believe there is a isascii()
function which test to see if its in that range of characters,
if there isnt which there might not be, you could always write
your own.


edit :
yea i dotn think there was a isascii() function thought
i saw it somewhere once, anyways you could write your
own using a few of these maybe?

open it manually and read it?