C++ 数据文件处理

Question

我在网上为我的学校项目获得了这段代码，它在 Turbo C++ 上运行良好，但为什么我运行在 visual studio enterprise 2015 中使用此代码并且 code::blocks 它给了我一些未知的输出.我附上了输出，请帮帮我，我试过 _strcmp 但没有解决问题。这是我试图在代码块中运行的代码。

#include <iostream>
#include<string.h>
#include <fstream>
#include <stdio.h>

using namespace std;

class crim_rec
{
    char name[20], sex[10], fathr_name[20], addrs[25], offense[20], blood[25], dob[9], reward[50];
    int crim_code;
    void disp();
public:
    void get();
    void wtf();
    void rff();
    void search();
    void del();
    void mod();
}c;
void crim_rec::get()
{
    puts("\nEnter name of criminal:");
    gets(name);
    puts("\nsex (m/f):");
    cin >> sex;
    puts("\nEnter date of birth:");
    gets(dob);
    puts("Enter blood group (Ap/An/Bp/Bn/ABp/ABn/Op/On:");
    gets(blood);
    puts("\nenter father's name:");
    gets(fathr_name);
    puts("enter address:");
    gets(addrs);
    puts("\nEnter crime commited:");
    gets(offense);
    puts("\nEnter reward on criminal:");
    gets(reward);
}
void crim_rec::disp()
{
    cout << "The record of criminal:\n";
    cout << "\nName of criminal: " << name;
    cout << "\nsex: " << sex;
    cout << "\nDOB: " << dob;
    cout << "\nBlood Group: " << blood;
    cout << "\nFather's name: " << fathr_name;
    cout << "\nAddress: " << addrs;
    cout << "\nCrime: " << offense;
    cout << "\nReward: " << reward;

}
void crim_rec::wtf()
{
    ofstream ofile;
    ofile.open("CBI.txt", ios::app);

    get();
    ofile.write((char*)&c, sizeof(c));
    ofile.close();
}
void crim_rec::rff()
{
    ifstream ifile;
    ifile.open("CBI.txt");
    ifile.seekg(0, ios::beg);
    ifile.read((char*)&c, sizeof(c));
    while (ifile)
    {
        disp();
        ifile.read((char*)&c, sizeof(c));
    }
    ifile.close();
}
void crim_rec::search()
{
    char m[20];
    ifstream ifile("CBI.txt");
    puts("Enter name of criminal which has to be searched");
    gets(m);
    ifile.seekg(0, ios::beg);
    ifile.read((char*)&c, sizeof(c));
    while (ifile)
    {
        if (strcmp(m, name) == 0)
            disp();
        ifile.read((char*)&c, sizeof(c));
    }
    ifile.close();
}
void crim_rec::del()
{
    char b[20];
    ifstream ifile;
    ifile.open("CBI.txt", ios::app);
    ofstream ofile;
    ofile.open("new.txt", ios::app);
    puts("Enter the name of the criminal whose records you want to del");
    gets(b);
    ifile.seekg(0, ios::beg);
    ifile.read((char*)&c, sizeof(c));
    while (ifile)
    {
        if (strcmp(b, name))
            ofile.write((char*)&c, sizeof(c));
        ifile.read((char*)&c, sizeof(c));
    }
    ifile.close();
    ofile.close();
    remove("CBI.txt");
    rename("new.txt", "CBI.txt");
}
void crim_rec::mod()
{
    char d[20];
    int p;
    puts("\nEnter name of criminal whose record you want to modify\n");
    gets(d);
    fstream f;
    f.open("CBI.txt", ios::in | ios::out);
    f.seekg(0, ios::beg);
    f.read((char*)&c, sizeof(c));
    int a = f.tellg();
    while (!f.eof())
    {
        if (!strcmp(d, name))
        {
            puts("\nPress 1 to change name\nPress 2 to change sex\nPress 3  to change date of birth\nPress 4 to change blood group\nPress 5 to change father's name\nPress 6 to change address\nPress 7 to change crime committed\nPress 8 to change reward on criminal\n");
            cin >> p;
            switch (p)
            {
            case 1:
                gets(name);
                break;
            case 2:
                cin >> sex;
                break;
            case 3:
                gets(dob);
                break;
            case 4:
                gets(blood);
                break;
            case 5:
                gets(fathr_name);
                break;
            case 6:
                gets(addrs);
                break;
            case 7:
                gets(offense);
                break;
            case 8:
                cin >> reward;
                break;
            }
            f.seekg(a - sizeof(c), ios::beg);
            f.write((char*)&c, sizeof(c));
        }
        f.read((char*)&c, sizeof(c));
        a = f.tellg();
    }
    f.close();
}
int main()
{
    int ch;
    char choice;
    do
    {
        cout << "\t Central Bureau of Investigation";
        cout << "\n ********************************************";
        cout << "\n\n *  1. View criminal details                 *";
        cout << "\n\n *  2. Add new criminal details               *";
        cout << "\n\n *  3. Search a criminal record              *";
        cout << "\n\n *  4. Delete a criminal record              *";
        cout << "\n\n *  5. Modify a criminal record              *";
        cout << "\n ********************************************";
        cout << "\n\n Enter your choice: ";
        cin >> ch;


        switch (ch)
        {
        case 1:

            c.rff();
            break;
        case 2:

            c.wtf();

            break;
        case 3:
            c.search();
            break;
        case 4:
            c.del();
            break;
        case 5:
            c.mod();
            break;
        default:
        {
            cout << "\nerror!";
        }
        break;
        }
        cout << "\ncontinue? (y/n)\n";
        cin >> choice;
    } while (choice == 'y');
    cout << "\nGood bye";
    return 0;
}

image 1 image 2

Answer 1

问题可能是由于使用了 puts() 和 gets()。他们似乎在输入中留下了尾随的换行符。分别用 std::cout 和 std::cin 替换它们为我修复了奇怪的输出（如果我正确理解你的问题）

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