Question

我正在尝试制作一个简单的信用卡还款计算器脚本，但似乎遇到了“while”循环的问题。它适用于较低的数字，但当你开始输入更高的数字时，它会冻结浏览器，然后你必须退出并重新打开。

这是我的JavaScript（jQuery）：

$('#calculate').click(function()
{
    var currentBalance = parseFloat($('#current_balance').val().substring(1)); // substring so it doesnt grab the £ sign
    var interestRate = parseFloat($('#interest_rate').val());
    var interestType = $('#interest_type').val();
    var monthlyPayment = parseFloat($('#monthly_payment').val().substring(1));
    var totalInterest = 0;
    var interest = 0;
    var months = 0;

    while(currentBalance > 0) // while there is still a balance on the card run the following
    {
        interest = (currentBalance/100)*interestRate; // find interest amount for this month

        currentBalance = currentBalance+interest; // add the interest to the balance

        currentBalance = currentBalance-monthlyPayment; // subtract monthly payment from balance

        totalInterest = totalInterest+interest; // total amount of interest paid
        months++;
    }

    var years = parseInt(months / 12);
    var remainingMonths = months % 12;

    totalInterest = Math.round(totalInterest);

    $('#clear_balance').val(years+' years and '+remainingMonths+' months');
    $('#interest_paid').val('£'+totalInterest);
});

这是我的HTML：

        <table id="card-info">
            <tbody>
                <tr>
                    <td><label for="current_balance">Current balance</label></td>
                    <td><input type="text" id="current_balance" /></td>
                </tr>
                <tr>
                    <td><label for="interest_rate">Interest rate</label></td>
                    <td>
                        <input type="text" id="interest_rate" />
                        <select id="interest_type">
                            <option value="monthly">Monthly</option>
                            <option value="yearly">Yearly</option>
                        </select>
                    </td>
                </tr>
                <tr>
                    <td><label for="monthly_payment">Monthly payment</label></td>
                    <td><input type="text" id="monthly_payment" /></td>
                </tr>
                <tr>
                    <td></td>
                    <td></td>
                </tr>
                <tr>
                    <td colspan="2"><button id="calculate">Calculate</button></td>
                </tr>
            </tbody>
        </table>
    </div>
    <div id="results">
        <table id="results-info">
            <tbody>
                <tr>
                    <td>
                        <label for="clear_balance">Time to clear balance</label><br />
                        <input type="text" id="clear_balance" />
                    </td>
                    <td>
                        <label for="interest_paid">Total interest paid</label><br />
                        <input type="text" id="interest_paid" />
                    </td>
                </tr>
            </tbody>
        </table>

我有什么问题吗？

Answer 1

您的代码没有考虑到每月支付的金额不足以支付每个月的利息。

在这种情况下，它会进入一个无限循环，因为贷款永远不会得到回报！

Answer 2

你的当前平衡永远是积极的！

虽然循环在使用更高的数字时崩溃

2 个答案: