Check Numbers Function

[mikefn]

Hi,

I have a variable that hold String, say $phone.
Now, I want to check if $phone holds only numbers[0-9]. Is there any build-in function for this? Otherwise, could someone help me to solve this?
Thanks.

Mike
😕

[eoghain]

Take a look at is_numeric().
http://www.php.net/manual/en/function.is-numeric.php

[mrmufin]

If you just need to check to see if somethings a number:

if(ereg("[0-9]", $variable)) {
	return TRUE;
} else {
	return FALSE;
}

If you need to check a phone number, this is what I use to check and consistently format North American telephone numbers. It'll return a string formatted as either 555-1212 or [phone] if the string parses as a valid North American telephone number. Really. Try it.

function IsUSPhone($v) {
        if(ereg("[a-zA-Z]",$v)) {
                return false;
        }
        $v = ereg_replace("[^0-9]","",$v);
        switch(strlen($v)) {
                case 7:
                        if(intval(substr($v,0,1)) < 2) {
                                return false;
                        }
                        $phone = substr($v,0,3) . '-' . substr($v,3,4);
                break;
                case 10:
                        if(intval(substr($v,0,1)) < 2) {
                                return false;
                        }
                        if(intval(substr($v,3,1)) < 2) {
                                return false;
                        }
                        $phone = '(' . substr($v,0,3) . ') ' . substr($v,3,3) . '-' . substr($v,6,4);
                break;
                case 11:
                        if(intval(substr($v,0,1)) != 1) {
                                return false;
                        }
                        if(intval(substr($v,1,1)) < 2) {
                                return false;
                        }
                        if(intval(substr($v,3,1)) < 2) {
                                return false;
                        }
                        $phone = '(' . substr($v,1,3) . ') ' . substr($v,4,3) . '-' . substr($v,7,4);
                break;
                default:
                        return false;
                break;
        }
        return $phone;
}

[frigidman]

mikefn's note about is_numeric() will work to test if its solely numbers or not. Which is a great use. However, if you still want to do something with the input, you could opt to clean up the string?

Below is a function I built up to process strings to keep certain characters. It works great for "cleaning" up user input from various text area and text fields.

For your case, you would use KeepInt() to keep only numbers from the string. Most people in the world want to type in phone numbers with dashes and parens sometimes for area codes/country codes.

You can by all means alter these functions to keep a dash as well, and spaces if you please. But I think what you are wanting to do is store the phone number as a solid number in like an INT field in a db? (The only real reason I see for wanting to ONLY keep the numbers).

	function Keep($orig_data,$keepchars='',$casecontrol='') {
		$keep_pattern = "/[^".$keepchars."]/".$casecontrol;
		return preg_replace($keep_pattern,"",$orig_data);
	}
	// Call as: Keep(the string, chars to keep, 'i' or nothing);
	// 'a-z0-9' Are also allowed for spans
	function KeepNum($orig_data) {
		return Keep($orig_data,'0-9\.','i');
	}
	function KeepInt($orig_data) {
		return Keep($orig_data,'0-9','i');
	}
	function KeepChar($orig_data) {
		return Keep($orig_data,'a-z','i');
	}
	function KeepSafeText($orig_data) {
		return Keep($orig_data,'a-z0-9 _\-\.','i');
	}

[frigidman]

I need to stop replying at the same time mrmufin does!! LOL! 😃