从数据库中读取值后显示已选中和未选中的复选框列表不起作用

Question

Here is my PHP code:

  <?php 
include ('../connection.php');
  $query00 = mysql_query("SELECT * FROM ta_subjects WHERE USER_ID='$login_session' AND Subject_ID='00000001'",$connection);
    while ($row00 = mysql_fetch_array($query00))
              { 
                $thisSub[] = $row00['TopicName'];
              }
    $arrlength = count($thisSub);
    ?>
<!--=====Math=======-->
      <div class="tab-content">
        <div id="math" class="tab-pane fade in active"><br>
          <?php
            include '../connection.php';
            $query = mysql_query("SELECT * FROM topics WHERE SubjectID = '1'",$connection);
            while ($row = mysql_fetch_array($query))
              { 
                $sub1 = $row['TopicName']; 
                ?>
                <div class="col-sm-6">
                <?php
                $a=0;
                do
                {
                  if($thisSub[$a] == $sub1)
                  {
                    ?>
                    <input type="checkbox" class="sub" name="checklist1[]" value="<?php echo $sub1;?>" disabled checked>
                    <?php
                    $a = $a + 1;
                  }
                  else
                    $a = $a + 1;
                }while($arrlength == $a);
                ?>
                    <input type="checkbox" class="sub" name="checklist1[]" value="<?php echo $sub1;?>" disabled>
                    <label><?php echo $sub1;?></label>
                </div>
                <?php
            }
          ?>
        </div>

It should look like this

I am comparing the list of all subjects from the database and the subjects with the same ID from the database also and mark it as checked. But it only displays the first checked check box and ends the loop. So the only checked check box is only Algebra. What am I missing here?

---

Solved

Solved it by putting the second check box in the else block instead of under the while loop as what @dreamster suggested.

Answer 1

I think

$query = mysql_query("SELECT * FROM topics WHERE SubjectID = '1'", $connection);

should be

$query = mysql_query("SELECT * FROM topics", $connection);

also change

if($thisSub[$a] == $sub1)

to

if(in_array($sub1, $thisSub))