I have an array being returned from the database that looks like so:
$data = array(201 => array('description' => blah, 'hours' => 0),
222 => array('description' => feh, 'hours' => 0);
In the next bit of code, I'm using a foreach
and checking the for the key in another table. If the next query returns data, I want to update the 'hours' value in that key's array with a new hours value:
foreach ($data as $row => $value){
$query = $db->query('SELECT * FROM t WHERE id=$row');
if ($result){
$value['hours'] = $result['hours'];
}
It's all fine except that I've tried just about every combination of declarations for the foreach loop, but I keep getting the error that the $value['hours']
is an invalid reference. I've tried declaring $value[]
... but that doesn't work either. I don't need to iterate through $value
so another foreach
loop isn't necessary.
Surely this is easier than my brain is perceiving it.
Here's the whole snippet:
forea开发者_开发技巧ch($_gspec as $key => $value){
$sql = sprintf('SELECT * FROM List WHERE specialtyID=%s', $key);
$query = $db->query($sql);
if ($query->num_rows() !== 0){
$result = $query->row_array();
$value['hours'] = $result['hours'];
}
}
You want
$data[$row]['hours'] = $result['hours']
$row
would be better named as $key
(that is what it is!)
Some people would suggest using pointers, but I find this way makes more sense to me.
You need to use ampersand in front of the $value in foreach to pass it by reference like this:
foreach ($data as $row => &$value){
$query = $db->query($sql);
if ($result){
$value['hours'] = $result['hours'];
}
}
More info here: http://php.net/manual/en/control-structures.foreach.php
As of PHP 5, you can easily modify array's elements by preceding $value with &. This will assign reference instead of copying the value.
Use reference ->
foreach ($data as $row => & $value) {
$query = $db->query('SELECT * FROM t WHERE id=$row');
// [...]
if ($result) {
$value['hours'] = $result['hours'];
}
}
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