Deprecated: Function ereg() & ereg_replace() - ereg

Question

i'm actually using a script i've used for years before and when i put it in my website, i got the error "Deprecated: Function ereg() & ereg_replace()". I'm actually unable to understand how to modify the ereg() things in preg() things. If someone is able to able, i'll appreciate!
Here is my code:
// couleur
$t=str_replace("[/color]", "</span>", $t);
$regCouleur="\[color= ?(([[:alpha:]]+)|(#[[:digit:][:alpha:]]{6})) ?\]";
$t=ereg_replace($regCouleur, "<span style=\"color: \\1\">", $t);
// taille des caractères
$t=str_replace("[/size]", "</span>", $t);
$regCouleur="\[size= ?([[:digit:]]+) ?\]";
$t=ereg_replace($regCouleur, "<span style=\"font-size: \\1px\">", $t);
// lien
$regLienSimple="\[url\] ?([^\[]*) ?\[/url\]";
$regLienEtendu="\[url ?=([^\[]*) ?] ?([^]]*) ?\[/url\]";
if (ereg($regLienSimple, $t)) $t=ereg_replace($regLienSimple, "\\1", $t);
else $t=ereg_replace($regLienEtendu, "\\2", $t);
// mail
$regMailSimple="\[email\] ?([^\[]*) ?\[/email\]";
$regMailEtendu="\[email ?=([^\[]*) ?] ?([^]]*) ?\[/email\]";
if (ereg($regMailSimple, $t)) $t=ereg_replace($regMailSimple, "\\1", $t);
else $t=ereg_replace($regMailEtendu, "\\2", $t);
// image
$regImage="\[img\] ?([^\[]*) ?\[/img\]";
$regImageAlternatif="\[img ?= ?([^\[]*) ?\]";
if (ereg($regImage, $t)) $t=ereg_replace($regImage, "<img src=\"\\1\" alt=\"\" border=\"0\" />", $t);
else $t=ereg_replace($regImageAlternatif, "<img src=\"\\1\" alt=\"\" border=\"0\" />", $t);
// Video
$regVidSimple="\[video\] ?([^\[]*) ?\[/video\]";
$regVidEtendu="\[video ?=([^\[]*) ?] ?([^]]*) ?\[/video\]";
if (ereg($regVidSimple, $t)) $t=ereg_replace($regVidSimple, "<p style=\"text-align: center;\"><object style=\"background-color: rgb(255, 255, 204); background-position: 50% 50%;\" data=\"\\1\" type=\"application/x-shockwave-flash\" height=\"190\" width=\"240\"><param name=\"src\" value=\"\\1\"></object></p>", $t);
else $t=ereg_replace($regVidEtendu, "<iframe title=\"YouTube video player\" width=\"240\" height=\"190\" src=\"\\1\" frameborder=\"0\" allowfullscreen>\\2</iframe>", $t);
Thanks for your answers !

Answer 1

Try this:
$regCouleur="/\[color=\s+(([[:alpha:]]+)|(#[[:digit:][:alpha:]]{6}))\s+\]/";
$t=preg_replace($regCouleur, "<span style=\"font-size: \\1px\">', $t);
By the way, could you please add a source and an expected string?