How to hide bank card number via Asterisks

If you want to hide bank card (credit / debit) number by asterisks, follow this simple function-

function hideNumberByAsterisks($cardNumber){
    return str_repeat('*', strlen($cardNumber) - 4) . substr($cardNumber, -4);  
}

If your input is -

123456789012

Output will be like that-

 ********9012

Thanks.