如何在C++中将对象数组中的内容复制到另一个数组中

How to copy contents in an array of object into another array in C++?

本文关键字:数组 复制 另一个 对象 C++      更新时间:2023-10-16
#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 respectivelyn";
    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,我必须将输入作为 10 人的名称和余额,并将输出显示为与最高余额对应的名称和余额。除了代码本身显示为注释的错误外,我还仅在对错误进行注释的地方在同一行中获得了另一段代码。另一个错误是:

IntelliSense: expression must be a modifiable lvalue

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

不能将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>(。看到这里如何将字符数组复制到 C 中的另一个字符数组?以进一步解释。

如果它像这样改变,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 respectivelyn";
        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();
}