添加两个 php - Adding two php

我正在为一家餐厅网站设计一个经过 php 验证的表单，一旦他们按下提交，该表单就会将用户定向到感谢页面，显示他们的预订详细信息。目前我有 2 个变量，一个名为"派对"，另一个名为"vip"。这些变量在回显时都显示字符串值。但是，我希望为它们分配一个 int 值，然后将它们相加以向用户显示总价。

目前我有这段代码，它似乎不起作用：

<b>Total Reservation Costs: </b> £
 <?php
 if ( $party == "1 Person (+£5)" )
   {
        $party = 5;
   }
    elseif if ( $party == "2 People (+£10)" )
   {
         $party = 10;
   }
   elseif if ( $party == "3 People (+£15)" )
   {
         $party = 15;
   }
   elseif if ( $party == "4 People (+£20)" )
   {
         $party = 20;
   }
    elseif if ( $party == "5 People (+£25)" )
   {
        $party = 25;
   }
   elseif if ( $party == "6 People (+£30)" )
   {
        $party = 30;
   }
    elseif if ( $party == "7 People (+£35)" )
   {
        $party = 35;
   }
   elseif if ( $party == "8 People (+£40)" )
   {
        $party = 40;
   }
   elseif if ( $party == "9 People (+£45)" )
   {
        $party = 45;
   }
   elseif if ( $party == "10+ People (+£50)" )
   {
        $party = 50;
   }
 if ( $vip == "Yes" )
   {
        $vip = 5;
   }
    elseif if ( $vip == "No" )
   {
        $vip = 0;
   }
 echo $party + $vip;
?>

如果有人知道如何让它工作，我将不胜感激，我是网络语言的新手，所以如果我的答案不是很清楚，我提前道歉。谢谢。

与其使用字符串来确定人数，为什么不直接使用 int

这是一个完整的程序

<form action="" method="POST">
    <select name="party">
        <option value="1">1 People (+£5)</option> 
        <option value="2">2 People (+£10)</option>
        <!-- ... -->
        <option value="10">10+ People (+£50)</option>
    </select>
    <input type="checkbox" name="vip" />
    <input type="submit" value="Confirm Reservation" /> 
</form>
<?php
if (isset($_POST['party']) && is_numeric($_POST['party'])) {
    $party = (int)$_POST['party'];
    $vip = isset($_POST['vip']) ? 5 : 0;
    echo "Total is: " . (($party * 5) + $vip);
}

elseif if应该只是else if

这不是 elseif if， its elseif

      总预订费用：  £ <?php
    if ( $party == "1 Person (+£5)" ){
    $party = 5;
    }
    elseif( $party == "2 People (+£10)" ){
    $party = 10;
    }
    elseif( $party == "3 People (+£15)" ){
    $party = 15;
    }
    elseif( $party == "4 People (+£20)" ){
    $party = 20;
    }
    elseif( $party == "5 People (+£25)" ){
    $party = 25;
    }
    elseif ( $party == "6 People (+£30)" ){
    $party = 30;
    }
    elseif( $party == "7 People (+£35)" ){
    $party = 35;
    }
    elseif( $party == "8 People (+£40)" ){
    $party = 40;
    }
    elseif( $party == "9 People (+£45)" ){
    $party = 45;
    }
    elseif( $party == "10+ People (+£50)" ){
    $party = 50;
    }
    else{    $party = 0;
    }
    if ( $vip == "Yes" ){
    $vip = 5;
    }
    elseif ( $vip == "No" ){
    $vip = 0;
    }
    else{
    $vip = 0;
    }
    echo $party + $vip;
?>

我建议也添加一个 else 语句，正如我在回答中添加的那样，以处理可能发生的任何其他情况。