我们在C ++类中做了一个非常相似的代码类型，但是我的版本没有正常工作，即使它是逐行（几乎）相同的。
我的代码是为了保存用户的口袋妖怪，他们可以随意添加和删除。我的显示功能正常，但我的添加和删除功能不正常。所有文件都在打开，但它不会覆盖文件，就像它应该的那样。真的不确定该做什么，我非常喜欢初学者而且我不太了解。
这是我到目前为止所得到的：
string name[100];
string type[100];
int level[100];
string newPokemon;
string newType;
int newLevel;
ifstream fin;
ofstream fout;
int numberOfPokemon = 0;
//Input Pokemon Info
cout << "Name of Pokemon: ";
getline(cin, newPokemon);
cin.ignore(100, '\n');
cout << "Pokemon type: ";
getline(cin, newType);
cin.ignore(100, '\n');
cout << "Pokemon level: "; //weird gap between "Pokemon type" and "pokemon level". I have to press enter twice from "pokemon type" to get to "pokemon level"
cin >> newLevel;
cin.ignore(5, '\n');
fin.open("pokemon.txt");
//Put file in array
if (fin.is_open())
{
while (isalnum(fin.peek()) && numberOfPokemon < 100)
{
getline(fin, name[numberOfPokemon]);
getline(fin, type[numberOfPokemon]);
fin >> level[numberOfPokemon];
fin.ignore(100, '\n');
if (name[numberOfPokemon] != newPokemon)
numberOfPokemon++;
}
fin.close();
}
//Output file
fout.open("pokemon.txt");
if (fout.is_open())
{
for (int i = 0; i < numberOfPokemon; i++)
{
fout << name[i] << "\n";
fout << type[i] << "\n";
fout << level[i] << "\n";
}
//Tack on new piece
fout << newPokemon << "\n";
fout << newType << "\n";
fout << newLevel << "\n";
fout.close();
cout << "Add Successful\n";
}
else
{
cout << "Add Failure\n";
}
现在我的删除功能：
string name[100];
string type[100];
int level[100];
int pokemonCount = 0;
string deletedPokemon = "";
bool found = false;
ifstream fin;
cout << "Which Pokemon would you like to delete?" << endl;
getline(cin, deletedPokemon);
cin.ignore(5, '\n');
fin.open("pokemon.txt");
if (fin.is_open())
{
while (isalnum(fin.peek()))
{
getline(fin, name[pokemonCount]);
getline(fin, type[pokemonCount]);
fin >> level[pokemonCount];
fin.clear();
fin.ignore(100, '\n');
if (deletedPokemon == name[pokemonCount])
{
pokemonCount--;
found = true;
}
pokemonCount++;
}
fin.close();
cout << "ya the file opened" << endl; //always appears
}
ofstream fout;
fout.open("pokemon.txt");
if (fout.is_open())
{
for (int i = 0; i < pokemonCount; i++)
{
fout << name[i] << "\n";
fout << type[i] << "\n";
fout << level[i] << endl;
}
fout.close();
cout << "pokemon removed\n";
cout << "the file opened."; //it is returning that the file opened in both occasions in this function but nothing is happening!
}
else
{
cout << "removal failure";
cout << "The file didn't open";
}
return found;
在这个功能的最后（如果我选择删除一个），它将提供＆＃34;你想添加一个口袋妖怪吗？＆＃34;但它不会让我输入答案，它只会结束程序。
答案 0 :(得分：0)
ofstream::open的默认行为是简单地打开文件进行读写。如果您要覆盖该文件，则需要在调用open。
fout.open("pokemon.txt", ios_base::in|ios_base::out|ios_base::trunc);
答案 1 :(得分：0)
确保您的文件未在属性下标记为只读。
此外，您的删除功能还有一个错误：
当你写出文件时，bfound应该用nDelete pokemon替换：
if (deletedPokemon == name[pokemonCount])
{
pokemonCount--;
found = true;
nDeleteIndex = i;
}
....
for (int i = 0; i < pokemonCount; i++)
{
if(i == nDeleteIndex)
continue;
fout << name[i] << "\n";
fout << type[i] << "\n";
fout << level[i] << endl;
}
现在它会重新编写你所有的小宠物而不会跳过你要删除的那个！
此外，如果用户有完整索引的155个小宠物，会发生什么。你想使用：
std::vector<string> names;
....
string szPokemon;
getline(fin, name[numberOfPokemon]);
names.push_back(szPokemon);
因此你不再有限制了！
答案 2 :(得分：0)
这里有更清晰的代码，它更易于维护，无论何时你从口袋妖怪添加/删除一个字段（Shiny？男/女？独特？），你将能够轻松地在CPokemonObject内部进行，而不必复制将代码粘贴100次。
#include "stdafx.h"
#include <iostream>
#include <fstream>
#include <string>
#include <sstream>
#include <vector>
using namespace std;
#define POKEMON_FILE "Pokemon.txt"
class CPokemon
{
public:
string szName;
string szType;
int nLevel;
CPokemon() : szName("Pika"), nLevel(10), szType("Lightning")
{};
void Read(ifstream &file)
{
file >> szName;
file >> szType;
file >> nLevel;
};
void Write(ofstream &file)
{
file << szName << endl;
file << szType << endl;
file << nLevel << endl;
};
void CreatePokemon()
{
//Input Pokemon Info
cout << "Name of Pokemon: ";
getline(cin, szName);
cout << "Pokemon type: ";
getline(cin, szType);
cout << "Pokemon level: "; //weird gap between "Pokemon type" and "pokemon level". I have to press enter twice from "pokemon type" to get to "pokemon level"
cin >> nLevel;
}
};
void WritePokemons(vector<CPokemon>& Pokemons)
{
ofstream fout;
fout.open(POKEMON_FILE);
//check the file open
if (!fout.is_open())
{
cout << "removal failure";
cout << "The file didn't open";
return;
}
//Write out all the pokemons
for (unsigned int i = 0; i < Pokemons.size(); i++)
Pokemons[i].Write(fout);
fout.close();
}
void ReadPokemons(vector<CPokemon>& Pokemons)
{
ifstream fin;
fin.open(POKEMON_FILE);
if (fin.is_open())
{
while (isalnum(fin.peek()))
{
CPokemon Pokemon;
Pokemon.Read(fin);
Pokemons.push_back(Pokemon);
}
fin.close();
cout << "ya the file opened" << endl; //always appears
}
}
bool DeletePokemon()
{
vector<CPokemon> Pokemons;
string szPokemonToDelete = "";
cout << "Which Pokemon would you like to delete?" << endl;
cin >> szPokemonToDelete;
//Read all pokemons
ReadPokemons(Pokemons);
ofstream fout;
fout.open("pokemon.txt");
//check the file open
if (!fout.is_open())
{
cout << "removal failure";
cout << "The file didn't open";
return false;
}
bool bFound = false;
for (unsigned int i = 0; i < Pokemons.size(); i++)
{
//Skip the pokemon to delete
if(Pokemons[i].szName == szPokemonToDelete)
{
bFound = true; //we found the pokemon to delete
continue;
}
Pokemons[i].Write(fout);
}
fout.close();
return bFound;
}
void AddPokemon()
{
vector<CPokemon> Pokemons;
//Read all pokemons from the file
ReadPokemons(Pokemons);
//Create the new porkemon
CPokemon Pokemon;
Pokemon.CreatePokemon();
//Add the pokemon to the list
Pokemons.push_back(Pokemon);
//Output file
WritePokemons(Pokemons);
}