$$wname

w变量名为变量，减少重复代码。

<?php
function w_w($w_arr, $link)
{
    $wres = true;
    foreach ($w_arr AS $w) {
        $wname = 'w' . $w;
        js_pure_alert($wname);
        if (!empty($$wname)) {
            $sql = 'UPDATE asin_email SET email_type=' . $w . ' WHERE id IN(' . substr($$wname, 0, strlen($$wname) - 1) . ')';
            if (!mysqli_query($link, $sql)) $wres = false;
        }
    }
    return $wres;
}