Question

#include "stdafx.h"
#include<iostream>
using namespace std;
class bank
{
public: char name[20];
public: float balance;
public: void get()
{
    cout << "\nEnter name and balance in Account respectively\n";
    cin >> name >> balance;
}
public: void display()
{
    cout << "Name: " << name << "    Balance: " << balance;
}
};
void main()
{
    int i = 0;
    bank b[10];
    bank max;
    bank temp;
    for (i = 0; i < 10; i++)
    {
        b[i].get();
    }
    for (i = 0; i < 10; i++)
    {
        if (b[i + 1].balance > b[i].balance)
        {
            max.balance = b[i + 1].balance;
            max.name = b[i + 1].name;//Error 1 error C2106: '=' : left operand must be l-value
        }
        else
        {
            temp.balance = b[i + 1].balance;
            temp.name = b[i + 1].name;//Error 2 error C2106: '=' : left operand must be l-value
            b[i + 1].balance = b[i].balance;
            b[i + 1].name = b[i].name;//Error 3 error C2106: '=' : left operand must be l-value
            b[i].balance = temp.balance;
            b[i].name = temp.name;//Error 4 error C2106: '=' : left operand must be l-value
            max.balance = b[i + 1].balance;
            max.name = b[i + 1].name;//Error 5  error C2106: '=' : left operand must be l-value
        }

    }
    max.display();
}

在这个程序中，我将输入作为10人的名字和余额，并将输出显示为与最高余额相对应的名称和余额。除了代码本身作为注释显示的错误之外，我还在相同的那些行中获得另一个代码，只有我对错误发表评论。另一个错误是：

IntelliSense: expression must be a modifiable lvalue

我正在使用Visual Studio Professional 2013，代码在Visual C ++中

Answer 1

您无法将char[]变量分配给另一个char[]变量。您应该使用strcpy函数来执行此操作（并且不要忘记先include<cstring>）。看到这个 how to copy char array to another char array in C?有待进一步说明。

如果它改变如此，那应该没问题：

#include<iostream>
#include<cstring>
using namespace std;
class bank
{
    public: char name[20];
    public: float balance;
    public: void get()
    {
        cout << "\nEnter name and balance in Account respectively\n";
        cin >> name >> balance;
    }
    public: void display()
    {
        cout << "Name: " << name << "    Balance: " << balance;
    }
};
void main()
{
    int i = 0;
    bank b[10];
    bank max;
    bank temp;
    char tempstr[20]; // use this for temporary string
    for (i = 0; i < 3; i++)
    {
        b[i].get();
    }
    for (i = 0; i < 2; i++) // you should change the upper bound to 9
                            // so it not crash when i = 9
    {
        if (b[i + 1].balance > b[i].balance)
        {
            max.balance = b[i + 1].balance;
            strcpy(max.name, b[i+1].name); // use strcpy
        }
        else
        {
            temp.balance = b[i + 1].balance;
            strcpy(temp.name, b[i+1].name); // use strcpy
            b[i + 1].balance = b[i].balance;
            strcpy(b[i+1].name, b[i].name); // use strcpy
            b[i].balance = temp.balance;
            strcpy(b[i].name, temp.name); // use strcpy
            max.balance = b[i + 1].balance;
            strcpy(max.name, b[i+1].name); // use strcpy
        }

    }
    max.display();
}

如何在C ++中将对象数组中的内容复制到另一个数组中？

1 个答案: