在for循环中访问DB Column数据（名称末尾有$ i时不起作用）

Question

I think my problem might be fairly simple, but I can't get it to work.

I have a custom DB Table with similar column names. The difference between columns is the number in the end, so we have name11, name12, name13. At the same time though, we have name21, name22, name23 and so on.

I am using a for loop inside of a for loop in order to retrieve the data of that specific column. The following code, however, does not work.

for($i=0; $i<10; $i++)
{
  echo('<table>');
  for($j=0; $j<10; $j++)
  {
    echo('<tr>');
      $field_name = $user_routines[$i]->exercise_name.($i+1).($j+1);
      echo('<td>' . $field_name . '</td>');
    echo('</tr>');
  } 
}

Besides that, I have also tried the following:

for($i=0; $i<10; $i++)
{
  echo('<table>');
  for($j=0; $j<10; $j++)
  {
    echo('<tr>');
      echo('<td>' . $user_routines[$i]->(exercise_name . ($i+1) . ($j+1)) . '</td>');
    echo('</tr>');
  } 
}

But it didn't work either.

Ps1: $user_routines is an array that contains my table rows for a specific user.

Thanks! =]

Answer 1

Try

  $tmp1 = ($i+1);
  $tmp2 = ($j+1);

  $id = "$tmp1"."$tmp2";
  echo '<td>' . $user_routines[$i]->{'exercise_name'.$id} . '</td>';

Assuming inside your array $user_routines[$i] is an object inside. Please paste a small piece of your array structure .