批量重命名文件

Posted 2020-10-12 鹅要长大

前言

实现代码的过程中经常需要将文件夹中的所有文件进行重命名，以方便对文件进行处理。

实现过程

1.测试代码；

/************************************************************************
* Copyright(c) 2017  AMY
* All rights reserved.
*
* File:    
* Brief: 
* Version: 1.0
* Author: 
* Email: [email protected]
* Date:    2017/10/27
* History:
* 20171027: ;

************************************************************************/
//-------------------------------------------------------------------------
#include <iostream>
#include <string>
#include <vector>
#include "opencv2/opencv.hpp"
#include "opencv2/contrib/contrib.hpp"
using namespace std;

int main()
{
    string oldFolder = "E:\\fatigue_detection\\dataset\\img\\";
    string oldType = "*.jpg";
    bool addPath = true;
    cv::Directory dir;
    vector<string> filenames = dir.GetListFiles(oldFolder, oldType, addPath);
    string newName;
    string oldName;
    string newType = ".png";
    for (int i = 0; i < filenames.size(); i++)
    {
        oldName = filenames[i];
        newName = oldFolder + to_string(i) + newType;
        ////method1
        //char *oldNamePointer, *newNamePointer;
        //oldNamePointer = (char *)malloc((oldName.size() + 1) * sizeof(char));
        //newNamePointer = (char *)malloc((newName.size() + 1) * sizeof(char));
        //strcpy(oldNamePointer, oldName.c_str());
        //strcpy(newNamePointer, newName.c_str());

        //rename(oldNamePointer, newNamePointer);
        //free(oldNamePointer);
        //free(newNamePointer);

        ////method2
        char* oldNamePointer = new char[(oldName.size() + 1) * sizeof(char)];
        char* newNamePointer = new char[(oldName.size() + 1) * sizeof(char)];
        strcpy(oldNamePointer, oldName.c_str());
        strcpy(newNamePointer, newName.c_str());

        rename(oldNamePointer, newNamePointer);
        delete [] oldNamePointer;
        delete [] newNamePointer;
    }
        
    return 0;

}

View Code

注意，不同类型之间的转换，比如char*和string、const char*和string等.

2.c++中new和delete的使用；

2.1）针对实体：

type_name * point_name = new type_name;
delete type_name;

注意，只能使用delete来释放使用new分配的内存；使用delete的关键在于只用于new分配的内存即new的地址.

2.2）针对动态数组：

type_name * point_name = new type_name [num_elements];
delete [] type_name;

注意，数组使用的是方括号[]；

2.3）使用new和delete应遵守的规则：

• 不要使用delete来释放不是new分配的内存；
• 不要使用delete释放同一个内存块两次；
• 如果使用new [] 为数组分配内存，则应使用delete [] 来释放；
• 如果使用new为一个实体分配内存，则应使用delete（没有方括号）来释放；
• 对空指针使用delete是安全的；

参考

1.here

2.书籍：c++ Primer Plus.

完