Question

我正在开发一个C ++银行系统。我能够正确地获得浮动，新的，值，当我尝试写入文件时，文件中没有数据。

else if (x == 2)
{
    cout << "You have selected option number 2. Deposit.\n";
    cout << "Please enter you account ID: ";
    cin >> ID;
    file.open("C:\\Users\\Raggulddon\\Desktop\\C++ supplement\\Cust_" + ID + ".dat", ios:: in | ios::out | ios::binary);

    if (!file)
    {
        cout << "Sorry the requested account could not be located.\n";
    }
    else
    {
        file >> firstname >> lastname;
        cout << endl << firstname << " " << lastname << endl;
        cout << "-----------------------------------\n";
        string line;
        while (getline(file, line))
        {

            // stringstream the getline for line string in file
            istringstream iss(line);

            if (iss >> date >> amount)
            {
                cout << date << "\t\t$" << showpoint << fixed << setprecision(2) << amount << endl;
                famount += amount;
            }

        }
        cout << "Your balance is $" << famount << endl;
        cout << "How much would you like to deposit today: $";
        cin >> amountinput;

        float newbal = 0;
        newbal = (famount += amountinput);


        cout << "\nYour new balance is: $" << newbal << ".\n";
        file << date << "\t\t" << newbal; //***This should be writing to file
        but it doesn 't.

file.close();

文本文件如下所示：

Tony Gaddis

05/24/12 100

05/30/12 300

07/01/12 -300

//控制台输出如下所示

Tony Gaddis

05/24/12 100

05/30/12 300

07/01/12 -300

您的余额是：＃1

您愿意存多少钱：＃2

您的新余额是：＃1 +＃2

写入文件

关闭文件。

//退出主循环::::

如何将其写入文件并保存，以及为什么会发生这种情况。

我尝试使用ostringstream并考虑如何使用istringstream作为输入。但它也没有工作：

float newbal=0;
newbal = (famount += amountinput);

ostringstream oss(newbal);
oss << date << "\t\t" << newbal;

我正在尝试自学C ++，所以任何相关的信息都会受到赞赏。

Answer 1

如果要编写文本文件，打开文件时不应使用“ios :: binary”。

为什么我的代码不会写入文件

1 个答案: