在php中设置选择输入的默认值

Question

我想在“-24小时”中设置默认值。所有选项都是用foreach动态生成的。

<select id="search3" name="date" onchange='this.form.submit();'> 
    <?php 
     $orderby_options3 = array(
      '-3day' => 'Last 3 days', 
      '-48hours' => '48 hours', 
      '-24hours' => '24 hours', 
     ); 
     foreach($orderby_options3 as $value3 => $label3) { 
      echo "<option ".selected($_GET['date'], $value3)." value='$value3'>$label3</option>"; 
     } 
    ?> 
</select> 

我知道我应该为选项添加“selected”参数，但在我的情况下，这是不可能的。

Answer 1

试试这个：

<select id="search3" name="date" onchange='this.form.submit();'> 
    <?php 
     $orderby_options3 = array(
      '-3day' => 'Last 3 days', 
      '-48hours' => '48 hours', 
      '-24hours' => '24 hours', 
     ); 
     foreach($orderby_options3 as $value3 => $label3) { 
      $selected = in_array($value3, [$_GET['date'] ?? null, '-24hours']) ? 'selected' : ''; 
      echo "<option $selected value='$value3'>$label3</option>"; 
     } 
    ?> 
</select> 

click to see the demo

Answer 2

如果你总是希望-24hours被选中，而这个页面将不会被用作编辑页面，那么你可以做这样的事情：

<select id="search3" name="date" onchange='this.form.submit();'> 
<?php 
    $orderby_options3 = array(
     '-3day' => 'Last 3 days', 
     '-48hours' => '48 hours', 
     '-24hours' => '24 hours', 
    ); 

    foreach($orderby_options3 as $value3 => $label3) { 
     $select = ($value3 == '-24hours') ? "selected='selected'":""; // see this line 
     echo "<option ".selected($_GET['date'], $value3)." value='$value3' $select>$label3</option>"; 
    } 
?>