PHP應用
<form action="piliangshanchu.php" method="post" >
<table border="1" cellspacing="0" cellpadding="0">
  <tr>
    <td width="200">
      <input type="checkbox" value="''" name="dx" onclick="checkall(this)" />
      編號</td>
    <td width="200">姓名</td>
    <td width="200">電話</td>
    <td width="200" >分組</td>
    <td width="200" >操作</td>
  </tr>
<tr>
    <td>
    <input type='checkbox' value='{$attr[0]}' name='item[]' class='ck' />
    {$attr[0]}</td> 
    <td>{$str}</td>
    <td>{$attr[2]}</td>
    <td>{$nation}</td>
</tr>
</table>
  <input type="submit" value="批量刪除"/>
  </form>

PHP應用
<script>
  function xxx(qx)
  {
//全選多選的選中狀態
    var ck = document.getElementsByClassName("ck");
 //讓下面所有的多選選中狀態改變
    if(qx.checked)
    {
      for(i = 0;i < ck.length ; i++)
      {
        ck[i].setAttribute("checked","checked");
//狀態改變為選中
      }
    }
    else
    {
      for(var i = 0;i < ck.length;i++)
      {
        ck[i].removeAttribute("checked");
//移除選中
      }
    }
  }
</script>

PHP應用
<?php
$arr = $_POST["item"];
$db = new mysqli("localhost","root","12345678","heiheihei");
//foreach($arr as $v)
//{
//  $sql = "delete from contacts WHERE id='{$v}'";
//  $db->query($sql);
//}
$str = implode("','",$arr);//拼接字符,
$sql = "delete from contacts WHERE id in('{$str}')";
//2','8','4
if($db->query($sql))//判斷是否查詢成功,
{
  header("location:shouye.php");
  //成功就跳轉
}
?>