先把id从数据库中提取出来 然后存在session里 比如
$sql = mysqli_query($conn,”select id from user where name = ‘”.$_POST[“name”]); if($sql === false){ echo “User doesn’t existe”; }else{ $info=mysqli_fetch_array($sql); if($info==””){ echo “empty id”; }else{ $_SESSION[“id”]=$info[“id”]; }}