老师的列子文档.txt

文件是程序设计中一个重要概念。所谓“文件”一般指：存处在外部介质上数据的集合。C对文件操作

#include <fstream>
#include <iostream>
using namespace std;

class A
{
public:
	int data;
	char ch[20];
};

int main()
{	
	A a;
	a.data = 200;
	strcpy(a.ch, "tom");

	fstream file("data.data", ios::out|ios::binary);
	if(file.fail())
	{
		cout << "Can not ..." << endl;
		return 0;
	}

	file.write(   (char*)(&a) , sizeof(a) );

	file.close();

// =================
	file.open("data.data", ios::in|ios::binary);
	if(file.fail())
	{
		cout << "Can not ..." << endl;
		return 0;
	}
	
	A b;
	file.read(    (char*)(&b), sizeof(b) );
	
	cout << b.data << endl;
	cout << b.ch << endl;

	file.close();
	
	return 0;
}