如何在php中的两列表中列出数据库中的选定项？

Question

So here's what I basically want to do. I have display a list of members and each of them have a check box next to it.

Just like this:

[ ] Spongebob

[ ] Patrick

[ ] Squidward

[ ] Sandy

[ ] Mr. Krab

[ OK ]

Whenever I select a number of members, and click OK, it will lead to a print page. In that print page, I want the members to be listed in two columns like this:

---

Spongebob | Patrick |

Squidward | Sandy |

Mr. Krab |

So far, I've only done it to be in a single column.

Here is my current code:

if(isset($_POST['ok'])){
if(!empty($_POST['check_list'])) {

$check_list = $_POST['check_list']; 
foreach ($check_list as $selected){
$sql = mysql_query("SELECT * FROM addmember WHERE id = '".$selected."' ORDER BY id");

$limit = 2;
$count = 0;

echo "<table>";

while ($row = mysql_fetch_array($sql)){
    $name = $row ['name'];

    if ($count < $limit){

        if ($count == 0){
            echo "<tr>";
            }

            echo "<td>$name";
        }else{
            $count = 0;
            echo "</tr><tr><td>
            $name</td><tr>";
            }
            $count++;
        }
        echo "</tr></table>";
        }

        echo '<script>window.print();</script>';
        }
    else{

    echo "<script>alert('Please select at least one member.');</script>";
    echo "<script>window.history.go(-1)</script>";
    }
}

Any suggestion and advice is very appreciated.. Thank you very much.

Answer 1

I think that your while is not necessary, because you only need one row. You have overcomplicated things a bit.

You need to check

• If $count is 0 - start row
• If $count == $limit or is last item of all - end row

And thats it. Between just echo <td> with $name.

So try this:

if(isset($_POST['ok'])){
  if(!empty($_POST['check_list'])) {

    $check_list = $_POST['check_list'];

    $itemsCount = count($check_list);
    $limit = 2;
    $count = $doneCount = 0;

    echo "<table>";

    foreach ($check_list as $selected){
      $sql = mysql_query("SELECT * FROM addmember WHERE id = '".$selected."' ORDER BY id LIMIT 1");
      $row = mysql_fetch_array($sql);

      $name = $row['name'];

      // Start new row
      if ($count == 0){
        echo "<tr>";
      }

      // Echo name
      echo "<td>".$name."</td>";

      // End row, increment counters
      if (++$count == $limit || $itemsCount == ++$doneCount ){
        $count = 0;
        echo "</tr>";
      }

    }

    echo "</tr></table>";

    echo '<script>window.print();</script>';
  }
  else{
    echo "<script>alert('Please select at least one member.');</script>";
    echo "<script>window.history.go(-1)</script>";
  }
}

++$count increments by one and then returns it, so we compare and increment all in one. See PHP: Incrementing/Decrementing Operators.

Don't use mysql_* functions anymore, cause they are deprecated. Instead use MySQLi or PDO.

Futher reading:

• Why shouldn't I use mysql_* functions in PHP?
• How can I prevent SQL injection in PHP?