Question

我是c ++的初学者，所以请耐心等待。我被要求编写一个程序，其中一个功能是从文件中删除一个记录，并使用数组将其放在另一个文件中（因此计数器的大小未知）。我尝试了很多不同的方法但无济于事。现在我收到abort()错误，我真的不知道该做什么或修复什么。非常需要你的帮助。

void DeletePatient ()
{
    ifstream infile;
    infile.open ("patients.txt");

    ofstream outfile;
    outfile.open ("deletedpatients.txt");

    int i=0, flag=0, counter=0, deleteID, deletedindex;

    //Read contents into array

    while(!infile.eof())
    {
        infile>>IDnumber[i]>> FirstName [i] >> LastName [i] >> PhoneNumber [i] >> Nationality [i];
        i++;
        counter++;
    }

    if ( !infile )
        cout << "Error opening file\n";
    else  
    {
        cout<<"Enter ID number of patient to be deleted\n";
        cin >> deleteID;

        for(i=0;i<counter;i++)
        {
            if(deleteID==IDnumber[i])
            {

                infile >> IDnumber [i] >> FirstName [i] >> LastName [i] >> PhoneNumber [i] >> Nationality [i];

                outfile << IDnumber [i] <<" "<< FirstName [i]<<" " << LastName [i]<<" " << PhoneNumber [i]<<" " << Nationality [i];

                flag++;

                for(deletedindex=i; i<counter; deletedindex++)
                {
                    IDnumber[deletedindex]=IDnumber[deletedindex+1];
                    FirstName[deletedindex]=FirstName[deletedindex+1];
                    LastName[deletedindex]=LastName[deletedindex+1];
                    PhoneNumber[deletedindex]=PhoneNumber[deletedindex+1];
                    Nationality[deletedindex]=Nationality[deletedindex+1];
                }

            }
        }

        infile.close();

        if(flag==0)
            cout<<"User does not exsist\n";
        else
        {
            ofstream updatefile;
            updatefile.open("patients.txt");

            for ( i=0 ; i < counter; i++ ) //update file
            {

                updatefile << IDnumber [i] <<" "<< FirstName [i]<<" " << LastName [i]<<" " << PhoneNumber [i]<<" " << Nationality [i];
            }   
            cout << "Patient is deleted" << endl;
            updatefile.close();
        }
    }

    outfile.close ();
}

Answer 1

让我们看一下这个循环的条件：

for(deletedindex = i; i < counter; deletedindex++)

循环内部i和counter都没有被修改，所以一旦你进入，你就不会离开（没有未定义的行为） - 无限循环

也许，你的意思是：

for(deletedindex = i; deletedindex + 1 < counter; deletedindex++)

无论如何，您的代码需要严格的重构 - 使用具有这些属性的一个对象数组，还要考虑使用std::vector。

使用数组删除记录

1 个答案: