如何从PHP中删除Indian Mobile Numbers中的国家/地区代码?

I'm receiving mobile numbers with country code (in 12 digits) from a API response. But I need the mobile number without the country code (in 10 digits).

What I'm receiving:

919999999999  

What I need:

9999999999  

What I have tried:

$mobile = "919999999999";
$split = preg_split("/[\]+/", $mobile);
$newmobile = $split[2].$split[3].$split[4].$split[5].$split[6].$split[7].$split[8].$split[9].$split[10].$split[11].$split[12];  

I know this is wrong. Please help!

Here's a version that will check that the mobile length is 12 and the first 2 characters contain the country code, before trying to remove them. This can be useful in case the input of the number can vary a bit:

$mobile = "919999999999";
if (strlen($mobile) == 12 && substr($mobile, 0, 2) == "91")
    $mobile = substr($mobile, 2, 10);
echo $mobile;

Just use substr() http://php.net/manual/en/function.substr.php

$string = '919999999999';
$string = substr($string, 2);
echo $string;

Which will output 9999999999

See it here https://3v4l.org/T2rHD

Since the question is tagged regex I guess you want regex.
This will get the last 10 digits of a number.
This means it will work with both with country code and without.

$phone = "919999999999";

Preg_match("/\d*(\d{10})/", $phone, $match);

Echo $match[1];

https://3v4l.org/qpTZ9

You could use substr:

$phoneNumber = '919999999999';
$phoneNumberNoCode = substr($phoneNumber, 2);

If you are dealing with phone numbers from other countries you could use preg_replace:

$countryCode = '91'; //Change here to match country code
$phoneNumber = '919199191999';
$phoneNumberNoCode = preg_replace('/'.$countryCode.'/', '', $phoneNumber, 1);