统计数组中元素出现的次数，以此判断是否要在产品名称后加上2,3,4……

大概代码

$goodsList = array(
  '0' => array('id' => 100, 'goodsName' => 'a'),
  '1' => array('id' => 101, 'goodsName' => 'a'),
  '2' => array('id' => 102, 'goodsName' => 'b'),
  '3' => array('id' => 103, 'goodsName' => 'b'),
  '4' => array('id' => 104, 'goodsName' => 'c'),
);
$goodsNameList = []; // 存储产品名称
foreach($goodsList as $key=>$value){
  // 统计数组中元素出现的次数，以此判断是否要在产品名称后加上2,3,4……
  $countArr = array_count_values($goodsNameList); 
  $goodsNameList[] = $value['goodsName'];
  $value['goodsName'] .= isset($countArr[$value['goodsName']]) ? '(' . ($countArr[$value['goodsName']] + 1) . ')' : '';
  echo $value['goodsName'] . '<br>';
}