How do i change the html element dynamically while iterating from database

Question

I am using a table to iterate the data from the database in a table. my html code is

    <table id="tablesorter"> 
        <thead> 
           <tr> 
           <th>Name</th> 
           <th>Location</th> 
           <th>Email</th> 
           <th>Phone</th> 
           </tr> 
        </thead> 
        <tbody> 
           <tr> 
           <td>Your Name</td> 
           <td>Somewhere</td> 
           <td>[email protected]</td> 
           <td>9999999999</td> 
           </tr> 
        <tr class="trow"> 
           <td>Your Name</td> 
           <td>Somewhere</td> 
           <td>[email protected]</td> 
           <td>9999999999</td>  
           </tr> 
           </tbody> 
   </table>

In my HTML table i am using a class for a table row to style it for every second table row. now while fetching the data from the database i want to make sure it does the same thing. it should add the class trow for every second table row.

what would be the logic behind this using with while loop?

Tomas Aschan · Accepted Answer · 2010-09-12 16:26:43Z

2

Basically, this is what you want to do:

Use a counter variable to keep track of the row you're at
On each row, check if the row counter is even. The easiest way to do this is with the modulo operator %.
```
6 % 2 == 0 // true
5 % 2 == 1 // true
4 % 2 == 1 // false
```

answered Sep 12, 2010 at 16:26

Tomas Aschan

61.2k62 gold badges268 silver badges425 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

d2burke · Accepted Answer · 2010-09-12 16:32:33Z

1

Seems to me that you could just use a ternary statement to set and unset the class variable as it loops through printing each row:

$class = ($class=='trow')?'':'trow';
<tr class="<?= $class ?>"> 
<td>Your Name</td> 
<td>Somewhere</td> 
<td>[email protected]</td> 
<td>9999999999</td> 
</tr>

So that each time a row is printed the $class variable would toggle between trow and nothing.

I use this logic when creating lists that export to excel quite often

answered Sep 12, 2010 at 16:32

d2burke

4,1213 gold badges41 silver badges52 bronze badges

2 Comments

Ibrahim Azhar Armar Over a year ago

wow so simple and easy to understand logic, that was brilliant answer and just the kind of solution i was looking for. thank you very much. :)

d2burke Over a year ago

No problem, Ibrahim. The ternary has become by best friend of late

Marc B · Accepted Answer · 2010-09-12 18:58:02Z

1

You'd use a simple state machine:

$evens = FALSE;
while($row = fetch_from_db()) {
     $evens = !$evens; // invert the even/odd flag
     $rowtype = ($evens === TRUE) ? ' class="trow"' : '';
     echo <<<EOL
<tr{$rowtype}>
   <td>etc...
</tr>

EOL;
}

Since $evens starts out false, on the first row it's inverted to true, which sets $rowtype to 'trow'. On the second row, it's inverted back to false, $rowtype becomes empty. On the 3rd row, we're back to true/trow, and so on, ping-ponging back and forth.

edited Sep 12, 2010 at 18:58

answered Sep 12, 2010 at 16:26

Marc B

362k44 gold badges433 silver badges508 bronze badges

Collectives™ on Stack Overflow

How do i change the html element dynamically while iterating from database

3 Answers 3

Comments

2 Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

Comments

2 Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related