C++程序练习

定义一个类CheckPath，它由两个public方法组成：

1） checkPath：检查传入的字符串指定的路径是否存在，存在返回true，否则返回false。

2） createFilePath：根据传入的字符串指定的路径，创建由 pathDepth指定的路径，例如：如果传入字符串为/home/user/aa/bb，如果指定的pathDepath为0，则不创建这个路径，如果pathDepath为1，则创建从/开始创建所有路径，如果pathDepath为2，则创建从/home开始创建所有路径。

class CheckPath{
public:
        bool checkPath(std::string &filePath);
        bool createFilePath(const char * path, int pathDepth);
};

checkpath.cpp源文件： 

#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
 
#define MAX_FILENAME_LEN        256
 
class CheckPath{
public:
        bool checkPath(std::string &filePath);
        bool createFilePath(const char * path, int pathDepth);
};
 
/* 测试指定目录是否存在 */
bool CheckPath::checkPath(std::string &filePath)
{
        char lastChar;
        struct stat buff;
        int istat;
        int isDir = 0;
        bool pathExists = false;
 
        int len = filePath.size();
 
        if (len == 0) return false;
 
        lastChar = filePath[len - 1];
 
        if (lastChar == '/'){
                filePath.resize(len - 1);
        }
 
        istat = stat(filePath.c_str(), &buff);
 
        if (!istat) isDir = (S_IFDIR & buff.st_mode);
 
        if (!istat && isDir){
                pathExists = true;
        }
 
        filePath.append("/");
 
        return pathExists;
}
 
/* 安pathDepath指定深度开始创建指定的目录 */
bool CheckPath::createFilePath(const char * path, int pathDepth)
{
        bool    result = true;
        char    * parts[MAX_FILENAME_LEN];
        int     num_parts;
        char    directory[MAX_FILENAME_LEN];
        char    nextDir[MAX_FILENAME_LEN];
        char    * saveptr;
        int     i = 0;
 
        /* donot create path */
        if (pathDepth == 0) return result;
 
        while ((path[i] == '/') && i < MAX_FILENAME_LEN){
                nextDir[i] = path[i];
                i++;
        }
 
        nextDir[i] = 0;
        printf("nextDir: %s\n", nextDir);
 
        strcpy(directory, &path[i]);
        printf("Directory: %s\n", directory);
 
        num_parts = 0;
        parts[num_parts] = strtok_r(directory, "\\/", &saveptr);
 
        while (parts[num_parts] != NULL){
                parts[++num_parts] = strtok_r(NULL, "\\/", &saveptr);
        }
 
//        for (i = 0; i < num_parts; i++){
//                printf("%d: %s\n", i+1, parts[i]);
        //}
 
        if (pathDepth < 0){
                pathDepth = num_parts + pathDepth;
                if (pathDepth < 1) pathDepth = 1;
        }
 
        for (i = 0; i < num_parts && result != false; i++){
                strcat(nextDir, parts[i]);
 
                if (i >= pathDepth)
                {
        //                printf("depath = %d,create path %s\n",i, nextDir);
                        if (mkdir(nextDir, 0777) != 0 && errno != EEXIST){
                                result = false;
                        }
                }
                strcat(nextDir, "/");
        }
 
        return result;
}
 
/* 测试主程序 */
int main(int argc, char ** argv)
{
        if (argc != 2){
                fprintf(stderr, "Usage: %s pathname\n", argv[0]);
                return -1;
        }
 
        std::string filePath = argv[1];
        std::cout << "Check File Path : " << filePath << " exists?" << std::endl;;
        CheckPath * pcp = new CheckPath();
 
        /* Test file path exists or not */
        std::cout << "*****************************************"<
        std::cout << "Test Function 1 checkPath:" << std::endl;
        if (pcp->checkPath(filePath))
        {
                std::cout << "FilePath:" << filePath <<" does exist" << std::endl;
        }
        else{
                std::cout << "FilePath:" << filePath << " does not exist" << std::endl;
        }
        std::cout << "*****************************************"<
 
        std::cout << "*****************************************"<
        std::cout << "Test Function 2 createFilePath:" << std::endl;
        std::cout << "Please enter a path to create:";
        std::cin >> filePath;
        std::cout << "The path to create :" << filePath << std::endl;
        int depth;
        std::cout << "Please enter the create depth:";
        std::cin >> depth;
        printf("Depth: %d\n", depth);
 
 
        if (pcp->createFilePath(filePath.c_str(), depth)){
                std::cout << "Create the "  << depth << " depth of file path " << filePath << std::endl;
        }
        else{
                std::cout << "can not create file path " << filePath << std::endl;
        }
        std::cout << "*****************************************"<
 
        delete pcp;
 
        return 0;
}

编译以上代码，观察结果：

orangepi@orangepi5:~/C_program$ ./checkpath aa
Check File Path : aa exists?
*****************************************
Test Function 1 checkPath:
FilePath:aa/ does exist
*****************************************
 
*****************************************
Test Function 2 createFilePath:
Please enter a path to create:/home/orangepi/C_program/aa/bb
The path to create :/home/orangepi/C_program/aa/bb
Please enter the create depth:3
Depth: 3
nextDir: /
Directory: home/orangepi/C_program/aa/bb
Create the 3 depth of file path /home/orangepi/C_program/aa/bb
*****************************************
orangepi@orangepi5:~/C_program$ ls aa/
bb

检查当前目录下aa目录时存在的，并且在aa目录下创建了一个bb目录。