verifying color code

[dotJoon]

<?php
$myColor="0000ff";
?>

I have a variable named $myColor like the above.

I like to verify whether the value of $myColor is color code or not.

The following code doesn't work correctly, but I hope it shows what I want.

code1

<?php
$myColor="0000ff";

if ( is_colorCode($myColor) )
{echo yes;}
else
{ echo no;}
?>

result1

yes

code2

<?php
$myColor="0xy0000";

if ( is_colorCode($myColor) )
{echo yes;}
else
{ echo no;}
?>

result2

no

[webdev1958]

you can use a regex to see if $myColor contains only 0-9 and/or a-f charachters

[felgall]

/^[0-9a-f]{6}$/i

[dotJoon]

/^[0-9a-f]{6}$/i

I am afraid that the code below which is one of my trials applying your code doesn't work correctly.

 if ( $myColor contains /^[0-9a-f]{6}$/i )
{echo yes;}
else
{echo no;}

[Immerse]

That's not PHP. There is no 'contains' in PHP.

<?php

$myColor="0000ff";

if(preg_match('/^[0-9a-f]{6}$/i', $myColor)) {
    echo "Match";
} else {
    echo "No match";
}

?>

[AnthonySterling]

Isn't a 3 digit Hex representation of a colour also valid?

[Cups]

$string = '000fff';
$len = strlen($string);

    if (ctype_xdigit($string) && ($len == 3 || $len == 6) ) 
        echo "The string $string is a valid color"; 

[AnthonySterling]

Very nice Cups, here's how the Imagine library validates an incoming colour declaration.

https://github.com/avalanche123/Imagine/blob/develop/lib/Imagine/Image/Color.php#L176

Truth be told, I guess it only really ensures the value supplied can be transformed into a colour, rather than validating the value.

[dotJoon]

Thank you to All.

[Immerse]

A 3 digit length is also valid, yes.
Cups, your version would allow stuff like.... #ayh9ep, right? Which isn't valid. The Imagine library doesn't check that either.

Right... /^[0-9a-f]{3,6}$/i' ... No, that'll allow 4 and 5 character colour codes too. And there my regex skillz fail.

[Cups]

"ayh9ep" fails the ctype_xdigit() test for me? (Win32, 5.2.6) as does "#ayh9ep"?

[Immerse]

Ah, my bad! I hadn't noticed the 'x' in ctype_xdigit.

My apologies, good sir.