Well may be it is to easy question but:
I want to sort the numbers by clicking an image. I thought that i make a form and add an imagefield.
<form id="form1" name="form1" method="post" action="index.php">
<input name="buyuka" type="image" src="resimler/azalt.gif" />
</form>
Then i will write these codes.
$sorgu='SELECT * FROM urunler';
if(isset($_POST['buyuka'])
{
$sorgu='SELECT * FROM urunler ORDER BY uyeno DESC';
}
$sonuclar=mysql_query($sorgu);
However it doesn't sort. When i try adding submit button in order to add imagefield, it works. So it means i make a really basic mistake but i cant find it.
Thank you for helping. :)
EDIT --- Solved
Actually as Pascal Martin said:
if(isset($_POST['buyuka_x'], $_POST['buyuka_y']))
{
$sorgu='SELECT * FROM urunler ORDER BY uyeno DESC';
}
It must be like that. Thanks :)
Just use var_dump()
to see what's in $_POST
:
var_dump($_POST);
And you'll see that, when your form is submitted using the <input type="image">
, you get :
array
'buyuka_x' => string '0' (length=1)
'buyuka_y' => string '0' (length=1)
So, there is no $_POST['buyuka']
-- instead, there are :
$_POST['buyuka_x']
$_POST['buyuka_y']
Which means your code should look like this (not testing for the unexistant buyuka
entry, and testing for the two _x
and _y
-- I suppose that testing for one of those should be enough) :
if(isset($_POST['buyuka_x'], $_POST['buyuka_y']))
{
$sorgu='SELECT * FROM urunler ORDER BY uyeno DESC';
}
Edit after the comments : I have no idea why it goes like that -- but having a .x
and a .y
is how it's defined in the HTML standard.
If you take a look at Forms in HTML documents, and scroll down a little, you'll be able to read :
When a pointing device is used to click on the image, the form is submitted and the click coordinates passed to the server.
The x value is measured in pixels from the left of the image, and the y value in pixels from the top of the image.
The submitted data includesname.x=x-value
andname.y=y-value
where "name" is the value of the name attribute, and x-value and y-value are the x and y coordinate values, respectively.
In PHP, the dots in parameters names are automatically replaced by and unerscore.
So :
name.x
becomes name_x
name.y
becomes name_y
As a source for that last statement, you can read Variables From External Sources - HTML Forms (GET and POST) (quoting) :
Dots and spaces in variable names are converted to underscores.
For example<input name="a.b" />
becomes$_REQUEST["a_b"]
.