- is_infinite: documentation ( source)
- var_dump: documentation ( source)
- is_nan: documentation ( source)
- filter_var: documentation ( source)
- trim: documentation ( source)
- define: documentation ( source)
<?php
// conditionally define PHP_INT_MIN since PHP 5.x doesn't
// include it and it's needed to validate integer casts
if (!defined("PHP_INT_MIN")) {
define("PHP_INT_MIN", ~PHP_INT_MAX);
}
var_dump(to_int(PHP_INT_MAX) === PHP_INT_MAX);
/**
* Returns the value as an int, or false if it cannot be safely cast
* @param mixed $val
* @return int
*/
function to_int($val)
{
switch (gettype($val)) {
case "integer":
return $val;
case "double":
if (!is_infinite($val) && !is_nan($val) && $val >= PHP_INT_MIN) {
// due to rounding issues, on 64-bit platforms
// the float must be less than PHP_INT_MAX
if (
(PHP_INT_SIZE === 8 && $val < PHP_INT_MAX) || // valid 64-bit
(PHP_INT_SIZE !== 8 && $val <= PHP_INT_MAX) // valid non-64-bit
) {
return (int) $val; // valid floats should cast
}
}
return false;
case "string":
$val = trim($val, " \t\n\r\v\f"); // trim whitespace
return filter_var($val, FILTER_VALIDATE_INT);
default:
return false;
}
}