如何从数组键中删除前导零

Question

I'm using Codeigniter 3 (calendar class) and I have this function to get calendar data (the table just has a date column and a data column):

    function get_calendar_data($year, $month) {
    $query = $this->db->select('date, data')->from('calendar')->like('date', "$year-$month", 'after')->get();
    $cal_data = array();
    foreach ($query->result() as $row) {
        $cal_data[substr($row->date,8,2)] = $row->data;
    }
    return $cal_data;
}

It works OK and produces an array for a month, $cal_data, consisting of days as the keys and values (in this case the names of colors) and var_dump typically looks like this:

array (size=6)
26 => string 'amber' (length=5)
27 => string 'red' (length=3)
28 => string 'red' (length=3)
25 => string 'amber' (length=5)
'04' => string 'red' (length=3)
'07' => string 'red' (length=3)

which the calendar requires. However, there is a problem with days that have leading zeros as the calendar appears to need them without. So the values do not show for 04 and 07. As a test, I rewrote the foreach loop to say:

$cal_data[substr($row->date,9,1)] = $row->data;

so the key would pick up only the final character of the date string, and in that case the values for 4 and 7 did indeed show correctly.

Is there a simple way to remove the leading zeros so the keys would be 4 and 7?

Answer 1

You can do this (note the cast to int):

foreach ($query->result() as $row) {
    $cal_data[(int)substr($row->date,8,2)] = $row->data;
}

Answer 2

I'm guessing since you have substr(..., 8, 2 ) I assume it's a full date like 2017-07-30 or something like it.
So that means you can use date() to manipulate the data.

$cal_data[date("j", $row->date)] = $row->data;

Date("j") is day number without leading zeros.
http://php.net/manual/en/function.date.php