only first four number of strings php code example

Example: php get first digit of number

// in case the number is a string
$s = '123';
$a = $s[0];  
echo $a; // 1

// in case the number is an integer

// Possibility 1
$k = 123;
$s = $k.''; // or: $s = (string)$k;
$a = $s[0];  
echo $a; // 1
 
// Possibility 2
$k = 123;
$a = floor($k/100);
echo $a; // 1
 
// Possibility 3
$k = 123;
$a = substr($k, 0, 1); 
echo $a; // 1