Question

我正在尝试使用一个循环来使用PHP计算每月的利率。我得到一个输出，但是数字本身会重复，并且月份也不输出。我如何输出该月，该月赚取的利息以及新的本金余额？

HTML

<form action='displayInterest.php' method ='POST'>
    <p>Principal
        <input type = 'text' name ='principal' maxlength='20'/>
    </p>
    <p>Interest Rate
        <input type='text' name='interestRate' maxlength = '20'/>
    </p>
    <p>Term
        <input type='text' name='term' maxlength='20'/>
    </p>
    <input type='submit' value='Calculate Interest'/>
</form>

PHP

<?php
    $principal = $_REQUEST['principal'];
    $interestRate = $_REQUEST['interestRate'];
    $term = $_REQUEST['term'];

    $MIR = $interestRate / 12;
    $MI = $principal / $MIR;
    $MB = $principal + $MI;

    $month = array('January', 'February', 'March', 'April', 'May', 'June', 'July', 'August', 'September','October', 'November', 'December');

    for($i = 0; $i < 13; $i++){    
        $MI += $month[0];
        echo($MI);
        echo('</br>');
    }    
?>

Answer 1

您错误地增加了月份，因此，它似乎打破了循环的其余部分。以下应该是您所需要的：

$MIR = $interestRate / 12;
$MI = $principal / $MIR;
$MB = $principal + $MI;

$month = array('January', 'February', 'March', 'April', 'May', 'June', 'July', 'August', 'September','October', 'November', 'December');

for($i = 0; $i < 13; $i++){    
    $MI = $month[$i];
    echo $MI .'<br>';
}

请注意，$ MI变量正在循环中被覆盖，我建议将其更改为其他内容，或者仅输出$ month，例如：

for($i = 0; $i < 13; $i++){
    echo $month[$i] .'<br>';
}

Answer 2

如果您只需要利息值和月份，请在循环中尝试以下代码：

for ($i = 0; $i < 13; $i++) {
    $rate = ($principal * $interestRate) / 100;
    echo $month[$i] . " => " . $rate;
    $principal += $rate;
    echo "</br>";
}

Answer 3

采用利率除以100（在循环之外，以避免每次计算）。

然后假设您的学期以月为单位，则对学期数进行循环：

<?php
    $principal = $_REQUEST['principal'];
    $interestRate = $_REQUEST['interestRate'] / 100;
    $term = $_REQUEST['term'];

    $month = array('January', 'February', 'March', 'April', 'May', 'June', 'July', 'August', 'September','October', 'November', 'December');

    $time = 1 / 12;     // Getting the "t" for the formula

    for ($i = 0; $i < $term; $i++) { // Run the loop for the number of terms
        $total = $principal * $interestRate * $time;    // Total is interest formula (P * r * t)
        $principal += $total;                           // Add total to principal to calculate for next month
        echo "<b>" . $month[$i] . "</b>: Interest: " . $total . ", Principal: " . $principal . "<br/>";      // Output month, interest earned, and new principal
    }
?>

我的本金为10000，利息为5，期限为5的输出为：

January: Interest: 41.666666666667, Principal: 10041.666666667
February: Interest: 41.840277777778, Principal: 10083.506944444
March: Interest: 42.014612268519, Principal: 10125.521556713
April: Interest: 42.189673152971, Principal: 10167.711229866
May: Interest: 42.365463457775, Principal: 10210.076693324

您可以根据需要设置输出格式。

在PHP中使用Loop来输出用户根据本金和利率获得的每月利息

3 个答案: