Php 从下拉框中保存所选选项 选择一名员工。。

提交此表单时，我将停留在同一页面上，但我希望在同一时间保留以前选择的选项可见。。我该怎么做？ 我试过：

document.getElementById（'select_employee'）。value=“”；

但它不起作用。

这里：

document.getElementById('select_employee').value = "<?php echo $_GET['select_employee'];?>";

foreach（$allemp作为$row）{
回显“$row['Etunimi']”-“$row['Sukunimi']”；
}

试试这个：

 foreach($allemp as $row){
     echo "<option " . (isset($_POST['select_employee']) && $_POST['select_employee'] == $row['Id'] ? ' selected ' : '') . " value=".$row['Id'].">".$row['Etunimi']." - ".$row['Sukunimi']."</option>";
}

 foreach($allemp as $row){
     echo "<option " . (isset($_POST['select_employee']) && $_POST['select_employee'] == $row['Id'] ? ' selected ' : '') . " value=".$row['Id'].">".$row['Etunimi']." - ".$row['Sukunimi']."</option>";
}

 $selected = ($row['Id'] == $_REQUEST['select_employee'])?'selected="selected"':'';
 echo '<option '.$selected.' value="'.$row['Id'].'">'.$row['Etunimi'].' - '. $row['Sukunimi'].'</option>';

<form method="post">
  <select name="select_employee" id="select_employee">
    <?php $allemp=$this->AllEmployees; ?>
    <option selected value="">Select an employee..</option>
    <?php foreach($allemp as $row){ 
      $selected = ($row['Id'] == $_REQUEST['select_employee'])?'selected="selected"':'';
     echo '<option '.$selected.' value="'.$row['Id'].'">'.$row['Etunimi'].' - '. $row['Sukunimi'].'</option>';
 } ?>
  </select>
  <input type="hidden" name="send" value="namesent">
  <input type="submit" value="submit" id="button">
</form>
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