Question

所以我的任务是我需要从一个数组创建一个html列表，并从一个数组中创建一个下拉菜单，并且如果我选择一个特定的学科，它应该只显示该学科及其老师。

我做了这个，但是如果我在数组中添加一个新的主题，它就会中断，所以我需要找到一个解决方案，如果我在数组中添加另一个项目，它应该工作而无需更改代码（我需要使用foreach和if语句）PS：我被困了几个小时，感谢您的帮助。

我的代码：

df2

Answer 1

<?php
$School = array(
    'science' => array(
        'teachersmith',
        'anotherteachersmith'
    ),
    'english' => array(
        'mr.vincent',
        'teachermichael',
        'coolestteacherever'
    ),
    'math' => array(
        'mathteacher',
        'mr.jason'
    ),
); 

$final_array = $School; // To not lose the $School array we store a copy as $final_array

    if (isset($_POST['submit'])){
        // We create a new array with $_POST["subjectoptions"] (e.g. science) and subarrays with the 2nd level of $School[$_POST["subjectoptions"]] (e.g. $School['science'] which gives us teachersmith and anotherteachersmith)
        $new_array[$_POST["subjectoptions"]] = $School[$_POST["subjectoptions"]]; 

        // Since we now want to work with the new array we set final_array to the new_array
        $final_array = $new_array;
    } 

    if (isset($_POST['reset'])){
        // If the reset button is clicked we restore the original array
        $final_array = $School;
    } 

echo "<ul class=listclass>";
foreach ($final_array as $subject => $teachername){
    echo "<li class=listclass>"."$subject". "</li>";

    echo "<ul class=listclass>";
    foreach ($teachername as $cNamen){
        echo "<li class=listclass>"."$cNamen". "</li>";
    }
    echo "</ul>";
}
echo "</ul>";
?>

<form method='POST'>
    <select name="subjectoptions">
        <option>Choose a subject</option>
            <?php 
            foreach ($School as $subject2 => $aDocentnames){ 
                echo "<option value=$subject2>$subject2</option>";
            } ?>
    </select>
    <input type="submit" name="submit" value="show selected subject"/>
</form>
<form method='POST'>
    <input type="submit" name="reset" value="show all subjects"/>
</form>

Answer 2

好吧，实际上，这不是您寻求某些作业帮助的地方。但是您有问题，需要一些帮助来解决。

这是解决方案-

这是您的数组：

<?php
$School = array(
    'science' => array(
        'teachersmith',
        'anotherteachersmith'
    ),
    'english' => array(
        'mr.vincent',
        'teachermichael',
        'coolestteacherever'
    ),
    'math' => array(
        'mathteacher',
        'mr.jason'
    )
);

在这里，我检查是否提交了表单，还检查了是否选择了主题。如果选择一个主题，那么我将创建一个循环，选择该主题作为该数组的索引。它显示了科目名称和教师列表。

if(isset($_POST['submit']) && !empty($_POST['subjectoptions'])){ $subjectoptions = $_POST['subjectoptions'];?>
    <ul class='listclass'>
        <ol class='listclass'><?php echo $_POST['subjectoptions'];?></ol>
        <?php foreach($School[$subjectoptions] as $teachername){?>
        <li class='listclass'><?php echo $teachername.".";?></li>
        <?php }?>
    </ul>
<?php }?>

这是表格，我使用属性来保持选中状态。

<form method='POST'>
    <select name="subjectoptions">
        <option>Choose a subject</option>
        <?php 
        $subjectName = array_keys($School);
        foreach ($subjectName as $subject){ 
            echo "<option ".(($subject == @$_POST['subjectoptions']) ? 'selected' : '')." value='".$subject."'>".$subject."</option>";
        }?>
    </select>
    <input type="submit" name="submit" value="show selected subject"/>
    <input type="submit" name="reset" value="show all subjects"/>
</form>

用php数组替换html列表

2 个答案: