How can I get the last 7 characters of a PHP string?

Question

How would I go about grabbing the last 7 characters of the string below?

For example:

$dynamicstring = \"2490slkj409slk5409els\";
$newstring = some_f         


        

Answer 1

for last 7 characters

$newstring = substr($dynamicstring, -7);

$newstring : 5409els

for first 7 characters

$newstring = substr($dynamicstring, 0, 7);

$newstring : 2490slk