Comparing Two Time stamps in PHP

Question

I am trying to prevent spam in my contact form. When anyone contact using contact form, I am saving his IP Address in Database with Current Time. If someone try contact, I am checking IP in database and if there IP address entry in Database, I am getting timestamp of it and comparing it with current timestamp but I think there something wrong with it and its giving me wrong time and so user are still able to send messages.

I have defined TimeZone like below

define('TIMEZONE', 'Asia/Kolkata');
date_default_timezone_set(TIMEZONE);
$date = date('Y/m/d h:i:s', time());

I am inserting write time in database same as echo in php.

Now I am getting and comparing both time like below

$last_time = $row['time'];
$current_time = $date;

    if(($current_time-strtotime($last_time )) > 1800) {
    //send mail
    }
    else {
    // give error
    }

I have tried echo both time and I am getting result like this

$last_time = 2018-09-23 07:56:37
$current_time = 2018/09/23 07:56:51
($current_time-strtotime($last_time ) = -1537667579

I don't know whats wrong with it.

Let me know if there anything wrong with it.

Answer 1

Also convert the current time into strtotime. Make sure both date format should be same

define('TIMEZONE', 'Asia/Kolkata');
date_default_timezone_set(TIMEZONE);
$date = date('Y/m/d h:i:s', time());

$last_time = $row['time'];
$current_time = $date;

if((strtotime($current_time)-strtotime($last_time )) > 1800) {
//send mail
}
else {
// give error
}