CODEWITHSUNDEEP
phpmysql
Eddie
Eddie

Reputation: 337

Php MySQL changing limit by select box selection

I'm currently facing a problem displaying results by a limit, my query ends in ORDER BY date DESC limit $limit and my html code is 

<select name="limit" id="limit">
    <option value="5">5</option>
    <option value="10">10</option>
    <option value="15">15</option>
    <option value="20">20</option>
</select>

In my PHP I have $limit=$_POST["limit"];

Now, this is basically working, except that on page load the form containing limit isn't posted, so I get a query error until I change the value of limit and submit it.

How can I have a default value selected on initial page load?

Upvotes: 0

Views: 968

Answers (5)

Punitha Subramani
Punitha Subramani

Reputation: 1477

Is this you are looking for

On page load selected="selected" takes default value.

<option value="15" selected="selected">15</option>

In PHP

 if(isset($_POST['limit']) && !empty($_POST['limit'])) {
  $limit = $_POST['limit']; 
 } else {
  $limit = '5'; /* Your default value*/
 }

In Query, try something like this

ORDER BY date DESC limit ".$limit;

Upvotes: 1

adey_888
adey_888

Reputation: 316

$_POST['limit'] will not exist until limit is posted e.g. by form submission.

If you want a default, I suggest:

$limit = filter_var($_POST['limit'], FILTER_VALIDATE_INT);
if(empty($limit) || !$limit) $limit = 10;

Then bind $limit to your prepared statement - assuming that's what you're using.

If you're not using prepared statements then you'd better check the content of $_POST['limit'] before concatenating it into a SQL statement like other posts here are suggesting.

Upvotes: 0

Ram Sharma
Ram Sharma

Reputation: 8809

you can use the conditional check in PHP

like this

$limit=isset($_POST["limit"])?$_POST["limit"]:5; // or change the value which you want to show onload

Upvotes: 0

Bruno Domingues
Bruno Domingues

Reputation: 43

You can test if the variable is empty then set it to a default value.

$limit = $_POST["limit"];
if ($limit == '') $limit = 5;

Upvotes: 1

Ende Neu
Ende Neu

Reputation: 15773

Set $limit to a default value like 0 and change it only if there's a posted value:

$limit = 0;
if(isset($_POST["limit"])) $limit = $_POST["limit"];

Also note that you shouldn't paste user input in queries since this could lead to sql injection.

Upvotes: 1

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