PHP：如何检查字符串是不是数字，但可以包含空格？

Question

The goal is to validate a number that is numeric and may or may not contain spaces.

Eg, both '1800 123 456' and '1800123456' are acceptable.

Checking to see if it is not numeric is easy:

if(!is_numeric($phone_number)) {
  //display error message
}

But I am stuck as to how to pass it with spaces.

Would anyone be able to point me in the right direction with this?

Answer 1

Just check without the spaces:

<?php
if(!is_numeric(str_replace(" ", "", $phone_number))) {
  //display error message
}

Or, if you want the overhead of a regular expression:

<?php
if (preg_match("/[^0-9 ]/", $phone_number)) {
    //display error message
}