功能php变量未知

Question

function scale($src) {
    $max = 350;
    if (!isset($max, $src))
        return;
    $src = str_replace(" ", "%20", $src[1]);
    $info = @getimagesize($src);
    $sw = $info[0];
    $sh = $info[1];
    $addclass = false;
    $max_em = 0.06 * $max;
    if ($max < max($sw, $sh)) {
        if ($sw > $sh)
            $new = array($max_em . "em", "auto");
        if ($sw < $sh)
            $new = array("auto", $max_em . "em");
        $addclass = true;
    } else
        $new = array("auto", "auto");
    $id = mt_rand(0000, 9999);
    if ($new[0] == "auto" && $new[1] == "auto")
        $img = "<img src=\"" . $src . "\" border=\"0\" alt=\"\" />";
    else
        $img = "<img id=\"r" . $id . "\" border=\"0\" alt=\"\" src=\"" . $src . "\" " . ($addclass ? "class=\"resized\"" : "") . " style=\"width:" . $new[0] . ";height:" . $new[1] . ";\" />";
    return $img;
}

I have this function to resize images. It does the job when images are bigger, but when they are 600x600 for example, i get Notice: Undefined variable: new in line

if ($new[0] == "auto" && $new[1] == "auto")

and

$img = "<img id=\"r" . $id . "\" border=\"0\" alt=\"\" src=\"" . $src . "\" " . ($addclass ? "class=\"resized\"" : "") . " style=\"width:" . $new[0] . ";height:" . $new[1] . ";\" />";

For this case, else, $new should be $new = array("auto", "auto"); , but it's not recognized.

Answer 1

Looking at following part, it becomes pretty clear:

if ($max < max($sw, $sh)) {
        if ($sw > $sh)
            $new = array($max_em . "em", "auto");
        if ($sw < $sh)
            $new = array("auto", $max_em . "em");
        $addclass = true;
    } else
        $new = array("auto", "auto");

translate it to values and you will see ..

if ($max < max($sw, $sh)) {
        if (600 > 600)
            $new = array($max_em . "em", "auto");
        if (600 < 600)
            $new = array("auto", $max_em . "em");
        $addclass = true;
        // None of the above ifs meet the case of 600x600 !!!!!
        // ----------------------------------------------------
    } else
        $new = array("auto", "auto");