Question

//
#include <fstream>
#include <string>
#include <iomanip>
#include <iostream>
void addMember();
void getChoice();
double nextID();
void removeMember();
void displayMember();
using namespace std;

void removeMember()
{   
    string membername;
    double line, deleteline;
    system("cls");
    cout<<"--------------------REMOVE MEMBER MENU--------------------\n";
    displayMember();
    ifstream memberList;
    memberList.open("member.txt");
    ofstream temp;
    temp.open("temp.txt");
    cout<<"Enter the member to remove: ";
    cin>>deleteline;
    //Statement to deleteline.
    temp.close();
    memberList.close();

}

从removeMember（）函数中，我应该使用什么语句？我应该使用while循环或数组（逐个搜索信息）？对于此功能，我需要执行的是当用户键入成员名称（删除行）时，该功能将跟踪名称并删除所需的行。

member.txt

0001    name1
0002    name2
0003    name3

temp.txt是一个空文件

对于搞砸的语法，我很抱歉，我是C ++编程的新手。

Answer 1

因此，您可以更改memberList的分隔符，而不会过于复杂，这应该只允许您使用istream_iterator。

void removeMember()
{
    system("cls");
    cout<<"--------------------REMOVE MEMBER MENU--------------------\n";
    displayMember();

    const ctype<char>::mask foo[ctype<char>::table_size] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, ctype_base::space };
    int deleteline = -1; // Changed this to an int and initialized in case cin fails
    ifstream memberList("member.txt"); // Used ifstream constructor
    ofstream temp("temp.txt"); // Used ofstream constructor

    cout << "Enter the member to remove: ";
    cin >> deleteline;
    memberList.imbue(local(foo.getloc(), new ctype<char>(foo)));
    copy_if(istream_iterator<string>(memberList), istream_iterator<string>(), ostream_iterator<string>(temp, "\n"), [&](const string& i){return --deleteline != 0;});
} // Removed the closes as they will happen automatically when the fstreams go out of scope

请注意，对于此黑客攻击，您应该#include <locale>，#include <iterator>和#include <algorithm>。而且这个hack假定'\n'是foo形成的第10个字符。

C ++如何删除文本文件中的行？

1 个答案: