PHP-从UTF-8转换为Unicode十六进制

您可以使用json_encode来执行此操作。。。

$str = "è";
$str = json_encode($str);
print $str;

这将打印''u00e8。如果需要，可以str_replace删除''u。如果您想要E而不是E，则可以使用strtoupper。

以下是我从的调试类中修改的一些内容

/**
 * Display utf && non-printable characters as hex
 *
 * @param string  $str     string containing binary
 * @param boolean $htmlout add html markup?
 *
 * @return string
 */
public function strInspect($str)
{
    $this->htmlout = $htmlout;
    $regex = <<<EOD
/
( ['x01-'x7F] )                 # single-byte sequences   0xxxxxxx  (ascii 0 - 127)
| (
  (?: ['xC0-'xDF]['x80-'xBF]    # double-byte sequences   110xxxxx 10xxxxxx
    | ['xE0-'xEF]['x80-'xBF]{2} # triple-byte sequences   1110xxxx 10xxxxxx * 2
    | ['xF0-'xF7]['x80-'xBF]{3} # quadruple-byte sequence 11110xxx 10xxxxxx * 3
  ){1,100}                      # ...one or more times
)
| ( ['x80-'xBF] )               # invalid byte in range 10000000 - 10111111   128 - 191
| ( ['xC0-'xFF] )               # invalid byte in range 11000000 - 11111111   192 - 255
| (.)                           # null (including x00 in the regex = fail)
/x
EOD;
    $str_orig = $str;
    $strlen = strlen($str);
    $str = preg_replace_callback($regex, 'strInspectCallback', $str);
    return $str;
}
/**
 * Callback used by strInspect's preg_replace_callback
 *
 * @param array $matches matches
 *
 * @return string
 */
protected function strInspectCallback($matches)
{
    $showHex = false;
    if ($matches[1] !== '') {
        // single byte sequence (may contain control char)
        $str = $matches[1];
        if (ord($str) < 32 || ord($str) == 127) {
            $showHex = true;
            if (in_array($str, array("'t","'n","'r"))) {
                $showHex = false;
            }
        }
    } elseif ($matches[2] !== '') {
        // Valid byte sequence. return unmodified.
        $str = $matches[2];
        $sequences = array(
            "'xef'xbb'xbf", // BOM
            "'xc2'xa0",     // no-break space
            // "'xE2'x80'x89", // thin space
            // "'xE2'x80'xAF", // narrow no-break space
            "'xEF'xBF'xBD",     // "Replacement Character"
        );
        foreach ($sequences as $seq) {
            if ($str === $seq) {
                $showHex = true;
                break;
            }
        }
    } elseif ($matches[3] !== '' || $matches[4] !== '') {
        // Invalid byte
        $str = $matches[3] != ''
            ? $matches[3]
            : $matches[4];
        $showHex = true;
    } else {
        // null char
        $str = $matches[5];
        $showHex = true;
    }
    if ($showHex) {
        $chars = str_split($str);
        foreach ($chars as $i => $c) {
            $chars[$i] = ''x'.bin2hex($c);
        }
        $str = implode('', $chars);
    }
    return $str;
}