checkboxes in php form doesn't work - php

Question

How can I use the conditional OR in a form with isset?
I have this but it does not work.
FORM HTML:
...
<input type="checkbox" name="carga1">
<input type="checkbox" name="carga2">
...
and the PHP
$cargas=array($_POST['carga1'],$_POST['carga2'],$_POST['carga3'],
$_POST['carga4'],$_POST['carga5'],$_POST['carga6'],
$_POST['carga7'],$_POST['carga8'],$_POST['carga9'],
$_POST['carga10'],$_POST['carga11'],$_POST['carga12'],
$_POST['carga13'],$_POST['carga14'],$_POST['carga15'],
$_POST['carga16'],$_POST['carga17'],$_POST['carga18']);
if(isset($cargas[0]) ││ isset ($cargas[1])){
$cargas[0]=5.62;
$cargas[1]=4.5;
echo "$cargas[0]<br>";
echo "$cargas[1]<br>";
}
i expect that this works but is not.

Answer 1

Only checked checkbox is posted to the server.You have to change your condition using pregmatch and work accordingly.
$postData = $_POST;
foreach ($postData as $key => $value) {
$match = preg_match('|cargas(\d+)|', $key, $matches);
if ($match) {
$index = $matches[1];
if($index == 0 || $index == 1){
// do your stuff which you would have done in case of $cargas[0] ,$cargas[1]
}
}
}

Answer 2

I think array is not Suitable way to do this try following
try this
<input type="checkbox" name="carga1">
<input type="checkbox" name="carga2">
.....................................
<input type="submit" name="submit">
<?php
if(isset($_POST['submit'])){
//
$category1=$_POST['carga1'];
$category2=$_POST['carga2'];
$category3=$_POST['carga3'];
if(isset($category1) ││ isset ($category2)){
$category1=5.62;
$category2=4.5;
echo "$category1<br>";
echo "$category2<br>";
}
}
?>

Answer 3

only the checked checkboxes get posted. so it needs slightly different appraoch.
You can acheive it like this-
put a hidden input with the same name as the checkbox that might not be checked. I think it works so that if the checkbox isn't checked, the hidden input is still successful and sent to the server but if the checkbox is checked it will override the hidden input before it. This way you don't have to keep track of which values in the posted data were expected to come from checkboxes.
<form>
<input type='hidden' id='testName' value='0' name='carga1'>
<input type='checkbox' id='testNameHidden' value='1' name='carga1'>
</form>
Before submitting the form , disabled the hidden field based on the checked condition.
<script>
if(document.getElementById("testName").checked){
document.getElementById('testNameHidden').disabled = true;
}
</script>
I personally think its the easiest approach for this.

Answer 4

ok, check boxes in html works as follows,
<input type="checkbox" name="carga1" value="1">
<input type="checkbox" name="carga2" value="123">
in php,
if the check box is in checked state during the submission, you will get
isset($_POST['carga1']) as true, else the form element would not be available in post data, hence false.
and in cheked state you will get value for
$_POST['carga1'] as 1 and
$_POST['carga2'] as 123
and if you want to group the check boxes in form you can use a single name for multiple check boxes and different values,
<input type="checkbox" name="carga[]" value="1">
<input type="checkbox" name="carga[]" value="2">
<input type="checkbox" name="carga[]" value="3">
<input type="checkbox" name="carga[]" value="4">
and in php you will get an array of selected values of the check boxes
$arr=$_POST['carga'];
and you can use foreach to iterate through the values,,,