flie 备份.txt

图书管理小程序实现了图书读者的输入,图书的借还.文件读写.

#include <stdio.h>
#include <string>
#include <stdlib.h>

using namespace std;

class FileEngine {
	private :

		FILE* ReadStream;
		FILE* WriteStream;
		string path;

		FileEngine () {
		
		}

	public :

		FileEngine (string p) {
			WriteStream = 0;
			ReadStream = 0;
			path = p;
		}

		~FileEngine () {
		}

		/* 结构体 , 结构体size , 结构体个数   return : 写入的结构体个数*/
		int put (void* data , int size , int counter) {

			if (!(WriteStream = fopen (path.c_str () , "ab"))) {
				printf ("写流初始化失败!");
			}

			int result = fwrite (data , size , counter , WriteStream);

			if (WriteStream) fclose (WriteStream);

			return result;
		}
		/* 结构体 , 结构体size , return : 读出的结构体的个数*/
		int get (void* data , int size) {

			if (!(ReadStream = fopen (path.c_str () , "rb"))) {
				printf ("读流初始化失败!");
			}

			int counter = 0;
			char* tmp = (char*)data;
			while (fread (&tmp[counter*size] , size , 1 , ReadStream))
				counter ++;
	
			if (ReadStream) fclose (ReadStream);

			return counter;
		}

		void Clear () {
			if (!(WriteStream = fopen (path.c_str () , "w+"))) {
				printf ("写流初始化失败!");
			}
			if (WriteStream) fclose (WriteStream);
		}
		void Build () {
			Clear ();
		}
};