Question

我想获取嵌套的foreach循环的第一个元素和结尾元素，条件对于第一个循环来说很好，但是对于第二个嵌套循环却不起作用。

PHP代码

$i = 0;
$len = count($category_tbl_data);
foreach($category_tbl_data as $row) {?>
   if ($i == 0) {
       // first element working fine
   }
   if ($i == $len - 1)
   {
      // last element working fine
   }

   $j=0;
   $len2 = count($services);
   foreach($services as $s){
    if($row['category']['cat_id'] == $s['Service']['category_id'])
    {
      if ($j == 0) {
       // first element working fine
    }
    if ($j == $len2 - 1)
    {
      // last element not working
    }

    }
   $j++;
  }
}

Image Here

Answer 1

已回答

是否有可能最后一个元素没有完全填充if($row['category']['cat_id'] == $s['Service']['category_id'])？

如果要对if ($j == 0) {}的确切第一个和最后一个元素进行操作，请尝试将if ($j == $len2 - 1){}和if($row['category']['cat_id'] == $s['Service']['category_id']){}放在$services之外，而不管$s是什么。

<?php

$len = count($category_tbl_data);
foreach($category_tbl_data as $i => $row) {
    if ($i == 0) 
    {
        // first element working fine
    }
    if ($i == $len - 1)
    {
        // last element working fine
    }

    $len2 = count($services);
    foreach($services as $j => $s){
        if ($j == 0) 
        {
            // first element 
        }
        if($row['category']['cat_id'] == $s['Service']['category_id'])
        {

        }
        if ($j == $len2 - 1)
        {
            // last element 
        }
        $j++;
    }
}
?>

如果要对满足$services的{{1}}的第一个和最后一个元素进行操作，则应事先传递一次数组以首先找出它们的确切索引。

$row['category']['cat_id'] == $s['Service']['category_id']

我如何找到PHP中嵌套的foreach循环的迭代

1 个答案:

已回答