用PHP检测轮数？

Question

How can I find out whether a float in PHP is a round number?

is_round(1.5); // false
is_round(1.0); // true
is_round(1.00000001); // false

Answer 1

Modification to Rob's code regarding sterofrog's comment. Code checks to ensure the value is also numeric.

function is_round($value) {
    return is_numeric($value) && intval($value) == $value;
}

Answer 2

function is_round( $value ) {
    return intval( $value ) == $value;
}

Answer 3

A much shorter version: !fmod($num,1) in PHP or this in JS: !($num % 1)

As a (more readable) function:

function is_round( $num ) {
  return !fmod($num, 1);
}

This works on the basis that any number that's not exactly 0 is falsey. You can use fmod($num,1) to get the decimals of a number; once you have those you can just ! them.

Answer 4

if ($value = round($value))

应该管用。

Answer 5

thierryreeuwijk在此页面上指定的功能应指定您的需求。