2回答

• 

  侠客岛的含笑

  2017-03-31 17:34:27

  A note to people to want to return an array of results - that is, an array of all the results from the query, not just one at a time.
  
  <?php
  
  // blah blah...
  call_user_func_array(array($mysqli_stmt_object, "bind_result"), $byref_array_for_fields);
  
  $results = array();
  while ($mysqli_stmt_object->fetch()) {
      $results[] = $byref_array_for_fields;
  }
  
  ?>
  This will NOT work. $results will have a bunch of arrays, but each one will have a reference to $byref.
  
  PHP is optimizing performance here: you aren't so much copying the $byref array into $results as you are *adding* it. That means $results will have a bunch of $byrefs - the same array repeated multiple times. (So what you see is that $results is all duplicates of the last item from the query.)
  
  hamidhossain (01-Sep-2008) shows how to get around that: inside the loop that fetches results you also have to loop through the list of fields, copying them as you go. In effect, copying everything individually.
  
  Personally, I'd rather use some kind of function that effectively duplicates an array than write my own code. Many of the built-in array functions don't work, apparently using references rather than copies, but a combination of array_map and create_function does.
  
  <?php
  
  // blah blah...
  call_user_func_array(array($mysqli_stmt_object, "bind_result"), $byref_array_for_fields);
  
  // returns a copy of a value
  $copy = create_function('$a', 'return $a;');
  
  $results = array();
  while ($mysqli_stmt_object->fetch()) {
      // array_map will preserve keys when done here and this way
      $results[] = array_map($copy, $byref_array_for_fields);
  }
  
  ?>
  
  All these problems would go away if they just implemented a fetch_assoc or even fetch_array for prepared statements...

  0 0
• 

  nadirvishun

  2017-02-08 13:54:54

  在百度知道中看到一个方法，原问题点这里，还挺巧妙的：

  $result = $mysqli_stmt->result_metadata();
  $fields = $result->fetch_fields();
  foreach($fields as $field){
      $column[]=&$out[$field->name];
  }
  call_user_func_array(array($mysqli_stmt,'bind_result'),$column);
  while ($mysqli_stmt->fetch()) {
      $t=array();
      foreach($out as $key=>$val){
          $t[$key]=$val;
      }
      $res[]=$t;
  }

  
  

  0 0