工作好几天终于把这个问题搞定了。呵呵，前些天linux老师给我们布置了一个作业，对window和linux的文件操作进行封装，并且将这两个封装写成一个基类的派生类，通过基类调用派生类访问。以前都是用直接访问派生类的，现在用基类访问派生类不知道怎么搞了，查了一下工厂模式可以帮我完成。代码如下：在Windows和Linux 下都能运行。/*赵丽 电子科大实现基于工厂模式的windows和linux文件操作的封装*///head.h
#include <map>#include <string>#include <stdio.h>class file;typedef file* (*FactoryFunction)();#ifdef WIN32 #define TEST 1#else#define TEST 0 #endif #define NAME “test”class DeviceFactory{public:static void Register(std::string name, FactoryFunction instanceFunction){m_FactoryFunctions[name] = instanceFunction;}static file* GetInstance(std::string name){if (m_FactoryFunctions.count(name)){return m_FactoryFunctions[name]();}else{return NULL;}}private:static std::map<std::string, FactoryFunction> m_FactoryFunctions;};std::map<std::string, FactoryFunction> DeviceFactory::m_FactoryFunctions;
class file{public:virtual void open() = 0;virtual void createfile(char* path)=0;virtual void writefile(char* path,char inText[])=0;virtual void readfile(char* path)=0;//virtual void closefile()=0;};
#if TEST==1#include <windows.h>#include <stdio.h>DWORD szBuffer[4];const char inText[] = “QQ:610847323”;char Length;class file_windows : public file{public:void open(){std::cout <<“windows class”<<std::endl;}
void createfile(char* path){ HANDLE hFile; hFile=CreateFile(path,GENERIC_WRITE,FILE_SHARE_READ,NULL,OPEN_ALWAYS,FILE_ATTRIBUTE_NORMAL,NULL);}
void writefile(char* path,char inText[]){HANDLE hFile;DWORD nBytes;hFile=CreateFile(path,GENERIC_WRITE,FILE_SHARE_WRITE,NULL,CREATE_ALWAYS,0,NULL);if(hFile!=INVALID_HANDLE_VALUE){WriteFile(hFile,inText, lstrlen(inText),&nBytes,NULL);CloseHandle(hFile);} }
void readfile(char* path){HANDLE hFile;DWORD dwBytesRead;char buffer[4096]; hFile = CreateFile(“hello.txt”, GENERIC_READ,0,NULL,OPEN_EXISTING,FILE_ATTRIBUTE_NORMAL,NULL); ReadFile(hFile, buffer, 4096, &dwBytesRead, NULL);CloseHandle(hFile); for(int j=0;j<5;j++){printf(“%c”,buffer[j]);}printf(“\n”);}
static file* CreateInstance(){static file_windows* windows0=new file_windows;return windows0;}};#elseclass file_linux : public file{public:void open(){std::cout<<“linux class”<<std::endl;}
void createfile(char* path){ fp=fopen(path,”w”);}
void readfile(char* path){printf(“reading start—-\n”);FILE * stream;char buffer[10];int i;stream = fopen(path,”r”);fread(buffer,sizeof(char),5,stream); fclose(stream);for(i=0;i<5;i++){printf(“%c”,buffer[i]);}printf(“\n”);}
void writefile(char* path,char buffer[]){printf(“writing start—-\n”);FILE * stream;int i;stream = fopen(path,”w”);fwrite(buffer,sizeof(char),5,stream);fclose(stream);for(i=0;i<5;i++){printf(“%c”,buffer[i]);}printf(“\n”);}
/* void open(const char* path,const char* mode){FILE * fp;fp=fopen(path,mode);if(fp==NULL){return;}fclose(fp);}*/
static file* CreateInstance(){static file_linux* linux0=new file_linux;return linux0;}};#endif
#if TEST==1FactoryFunction fun=&file_windows::CreateInstance;#elseFactoryFunction fun=&file_linux::CreateInstance;#endif
//main.cpp#include <iostream>#include “head.h”using namespace std;int main(){DeviceFactory::Register(NAME,fun);file* file = DeviceFactory::GetInstance(NAME);file->open();file->createfile(“hello0.txt”);file->writefile(“hello.txt”,”hello”);file->readfile(“hello.txt”);delete file;return 0;}
，离开之后，我想你不要忘记一件事：不要忘记想念我。
