tp5 gets the id value of the data just submitted

tp5 implements commitform (document)When you get the id value of the generated data, store the id value in another table, use it as a foreign key, and add a new piece of data to the foreign key table (i.e., the related table).

   
  $labelids=htmlspecialchars($data1['labelids']);

  // $userid=$db_res['id'];
  if($labelids){
      $lbids=explode(',',$labelids);
      foreach ($lbids as $k =>$val){
          if(!empty($val)){
              $lbdata1=[
                  'userid'=>$userid,
                  'labelid'=>$val,
                  'create_time'=>request()->time(),
              ];
              $db_res1 = Db::name("userlabel")->insert($lbdata1); // Information on the type of user association
          }
      }
  }

Error situation:

 $db_res = Db::name("user")->insert($data);  //When the entry is not commented, two new entries are added to the main table.
   $userid = Db::name("user")->insertGetId($data);
  $labelids=htmlspecialchars($data1['labelids']);

  // $userid=$db_res['id'];
  if($labelids){
      $lbids=explode(',',$labelids);
      foreach ($lbids as $k =>$val){
          if(!empty($val)){
              $lbdata1=[
                  'userid'=>$userid,
                  'labelid'=>$val,
                  'create_time'=>request()->time(),
              ];
              $db_res1 = Db::name("userlabel")->insert($lbdata1); // Information on the type of user association
          }
      }
  }