动态数组类指针

时间:2016-04-17 06:13:08

标签: c++ arrays pointers

我正在尝试创建一个指向类ElectricityBill的实例数量的动态指针数组。

我目前的方法是创建一个动态电力数据阵列(目前没有任何东西),然后创建一个POWERBill的单个实例,创建另一组尺寸较大的电力账单,复制旧动态阵列的所有实例,最后添加新的。

我尝试过的代码在

之下
// Define the dyn array
int EBcount = 0;
ElectricityBill **EB = new ElectricityBill*[EBcount];

// Create a temp instance and input the data
ElectricityBill *tempEB = new ElectricityBill;
std::cin >> *tempEB;

std::cout << *tempEB << std::endl;

// Create a new dyn array and copy the instances accross
EBcount++;
ElectricityBill **temp = new ElectricityBill*[EBcount];
for (int i = 0; i < EBcount-1; i++) {
    temp[i] = EB[i];
}

// Append the new instance at the end and delete the old array
temp[EBcount-1] = tempEB;
delete [] EB;
EB = temp;

std::cout << temp[0] << std::endl;
std::cout << EB[0] << std::endl;

,输出

E;name;1;2;3;acc;add;1/1/2000;1/2/2000;22.721;2.2721
0x100500000
0x100500000

值得注意的是,我在类定义中重载了运算符<<>>>>运算符提示用户输入数据并将输入数据存储在类的私有变量部分中,<<运算符的构建方式如下:

std::ostream& operator<<(std::ostream &stream, ElectricityBill &printStream) {

    stream << "E;"
    << printStream.billerName << ";"
    << printStream.billerCode << ";"
    << printStream.referenceNumber << ";"
    << printStream.accountNumber << ";"
    << printStream.accountName << ";"
    << printStream.address << ";"
    << printStream.periodStartDate.day << "/" << printStream.periodStartDate.month << "/" << printStream.periodStartDate.year << ";"
    << printStream.periodDueDate.day << "/" << printStream.periodDueDate.month << "/" << printStream.periodDueDate.year << ";"
    << printStream.amountDue << ";"
    << printStream.totalGST;

    return stream;
}

由于某种原因,输出正在输出内存地址而不是预期的数据。为什么会发生这种情况,我该怎么做才能解决它?

1 个答案:

答案 0 :(得分:2)

您的重载操作符接受对ElectricityBill的引用,但您似乎正在提供指针。因此,正在使用<<的默认实现,它打印内存位置。尝试:

std::cout << *temp[0] << std::endl;
std::cout << *EB[0] << std::endl;