我如何根据使用 php 选择的用户输入计算总价

Question

我想计算来自 $_SESSION 的用户输入的总价格。但是，我的代码似乎有问题。

 <label>Seats STA:</label>

        <select name="seats[STA]" id="STA">

            <option value="0">0</option>

            <option value="1">1</option>

            <option value="2">2</option>

            <option value="3">3</option>

            <option value="4">4</option>

            <option value="5">5</option>

            <option value="6">6</option>

            <option value="7">7</option>

            <option value="8">8</option>

            <option value="9">9</option>

            <option value="10">10</option>

        </select>

        <span class="error">* Please select atleast 1 seat <?php echo $seatErr ;?></span>

$_SESSION['seats']['STA']=$_POST['seats']['STA'];

$sta = 15;

$stp = 5;

$stc = 7.5;

$fca = 30;

$fcp = 20;

$fcc = 15;

$totalamount = "0.0";

$totalamount =  $_SESSION['seats']['STA'] * $sta +

                $_SESSION['seats']['STP'] * $stp +

                $_SESSION['seats']['STC'] * $stc +

                $_SESSION['seats']['FCA'] * $fca +

                $_SESSION['seats']['FCP'] * $fcp +

                $_SESSION['seats']['FCC'] * $fcc;

$tax = 0.1;

$totalprice = $totalamount * (1+$tax);                

number_format($totalprice,2);

我的问题是，

1. 是$sta节省价格的正确方法吗？

2. 如果没有，我可以在哪里保存选择表格中的产品价格？

3. 是number_format($totalprice,2);显示小数点后 2 位的正确方法吗？？

感谢阅读我的代码！！

Answer 1

您可以将价格保存在数组中。例如，您也可以从 JSON 文件或数据库中读取它。价格不应该由用户发送。如果你想显示价格是，但如果你想继续计算价值，round($total_price, 2)是更合适的方法。代码：$_PRICES = array(&nbsp; &nbsp; "STA" => 15,&nbsp; &nbsp; "STP" => 5,&nbsp; &nbsp; "STC" => 7.5,&nbsp; &nbsp; "FCA" => 30,&nbsp; &nbsp; "FCP" => 20,&nbsp; &nbsp; "FCC" => 15);$total_price = 0;foreach ($_SESSION['seats'] as $item => $amount) {&nbsp; &nbsp; $price = $_PRICES[$item];&nbsp; &nbsp; if ($price != null) {&nbsp; &nbsp; &nbsp; &nbsp; $total_price += $amount * $price;&nbsp; &nbsp; }}$tax = 0.1;$total_price *= 1+$tax;echo number_format($total_price,2);