中文汉字 转成数字 编码 方法【转】

<?php
class StrFormat_F10{
static function encode($var){
$ascii = '';
$strlen_var = strlen($var);
for ($c = 0; $c < $strlen_var; ++$c) {

$ord_var_c = ord($var{$c});

switch (true) {
case $ord_var_c == 0x08:
$ascii .= '\b';
break;
case $ord_var_c == 0x09:
$ascii .= '\t';
break;
case $ord_var_c == 0x0A:
$ascii .= '\n';
break;
case $ord_var_c == 0x0C:
$ascii .= '\f';
break;
case $ord_var_c == 0x0D:
$ascii .= '\r';
break;

case $ord_var_c == 0x22:
case $ord_var_c == 0x2F:
case $ord_var_c == 0x5C:
$ascii .= '\\'.$var{$c};
break;

case (($ord_var_c >= 0x20) && ($ord_var_c <= 0x7F)):
$ascii .= $var{$c};
break;

case (($ord_var_c & 0xE0) == 0xC0):
$char = pack('C*', $ord_var_c, ord($var{$c + 1}));
$c += 1;
$utf16 = self::utf82utf16($char);
$ascii .= '&#'.hexdec(bin2hex($utf16)).';';
break;

case (($ord_var_c & 0xF0) == 0xE0):
$char = pack('C*', $ord_var_c,
ord($var{$c + 1}),
ord($var{$c + 2}));
$c += 2;
$utf16 = self::utf82utf16($char);
$ascii .= '&#'.hexdec(bin2hex($utf16)).';';
break;

case (($ord_var_c & 0xF8) == 0xF0):
$char = pack('C*', $ord_var_c,
ord($var{$c + 1}),
ord($var{$c + 2}),
ord($var{$c + 3}));
$c += 3;
$utf16 = self::utf82utf16($char);
$ascii .= '&#'.hexdec(bin2hex($utf16)).';';
break;

case (($ord_var_c & 0xFC) == 0xF8):
$char = pack('C*', $ord_var_c,
ord($var{$c + 1}),
ord($var{$c + 2}),
ord($var{$c + 3}),
ord($var{$c + 4}));
$c += 4;
$utf16 = self::utf82utf16($char);
$ascii .= '&#'.hexdec(bin2hex($utf16)).';';
break;

case (($ord_var_c & 0xFE) == 0xFC):
$char = pack('C*', $ord_var_c,
ord($var{$c + 1}),
ord($var{$c + 2}),
ord($var{$c + 3}),
ord($var{$c + 4}),
ord($var{$c + 5}));
$c += 5;
$utf16 = self::utf82utf16($char);
$ascii .= '&#'.hexdec(bin2hex($utf16)).';';
break;
}
}

return $ascii;
}

static function decode($var){
$chrs = $var;
$utf8 = '';
$strlen_chrs = strlen($chrs);

for ($c = 0; $c < $strlen_chrs; $c++) {

$substr_chrs_c_2 = substr($chrs, $c, 2);
$ord_chrs_c = ord($chrs{$c});

switch (true) {
case $substr_chrs_c_2 == '\b':
$utf8 .= chr(0x08);
++$c;
break;
case $substr_chrs_c_2 == '\t':
$utf8 .= chr(0x09);
++$c;
break;
case $substr_chrs_c_2 == '\n':
$utf8 .= chr(0x0A);
++$c;
break;
case $substr_chrs_c_2 == '\f':
$utf8 .= chr(0x0C);
++$c;
break;
case $substr_chrs_c_2 == '\r':
$utf8 .= chr(0x0D);
++$c;
break;

case $substr_chrs_c_2 == '\\"':
case $substr_chrs_c_2 == '\\\'':
case $substr_chrs_c_2 == '\\\\':
case $substr_chrs_c_2 == '\\/':
if (($delim == '"' && $substr_chrs_c_2 != '\\\'') ||
($delim == "'" && $substr_chrs_c_2 != '\\"')) {
$utf8 .= $chrs{++$c};
}
break;

case preg_match('/\&\#[0-9]{5};/i', substr($chrs, $c, 8)):
$tmpstr=substr($chrs, $c, 8);
$tmpstr=dechex(substr($tmpstr, 2, 5));
$utf16 = chr(hexdec(substr($tmpstr, 0, 2)))
. chr(hexdec(substr($tmpstr, 2, 2)));
$utf8 .= self::utf162utf8($utf16);
$c += 7;
break;

case ($ord_chrs_c >= 0x20) && ($ord_chrs_c <= 0x7F):
$utf8 .= $chrs{$c};
break;

case ($ord_chrs_c & 0xE0) == 0xC0:
$utf8 .= substr($chrs, $c, 2);
++$c;
break;

case ($ord_chrs_c & 0xF0) == 0xE0:
$utf8 .= substr($chrs, $c, 3);
$c += 2;
break;

case ($ord_chrs_c & 0xF8) == 0xF0:
$utf8 .= substr($chrs, $c, 4);
$c += 3;
break;

case ($ord_chrs_c & 0xFC) == 0xF8:
$utf8 .= substr($chrs, $c, 5);
$c += 4;
break;

case ($ord_chrs_c & 0xFE) == 0xFC:
$utf8 .= substr($chrs, $c, 6);
$c += 5;
break;

}

}

return $utf8;
}

static function utf82utf16($utf8){
if(function_exists('mb_convert_encoding')) {
return mb_convert_encoding($utf8, 'UTF-16', 'UTF-8');
}

switch(strlen($utf8)) {
case 1:
return $utf8;

case 2:
return chr(0x07 & (ord($utf8{0}) >> 2))
. chr((0xC0 & (ord($utf8{0}) << 6))
| (0x3F & ord($utf8{1})));

case 3:
return chr((0xF0 & (ord($utf8{0}) << 4))
| (0x0F & (ord($utf8{1}) >> 2)))
. chr((0xC0 & (ord($utf8{1}) << 6))
| (0x7F & ord($utf8{2})));
}
return '';
}

static function utf162utf8($utf16){
if(function_exists('mb_convert_encoding')) {
return mb_convert_encoding($utf16, 'UTF-8', 'UTF-16');
}
$bytes = (ord($utf16{0}) << 8) | ord($utf16{1});
switch(true) {
case ((0x7F & $bytes) == $bytes):
return chr(0x7F & $bytes);

case (0x07FF & $bytes) == $bytes:
return chr(0xC0 | (($bytes >> 6) & 0x1F))
. chr(0x80 | ($bytes & 0x3F));

case (0xFFFF & $bytes) == $bytes:
return chr(0xE0 | (($bytes >> 12) & 0x0F))
. chr(0x80 | (($bytes >> 6) & 0x3F))
. chr(0x80 | ($bytes & 0x3F));
}
return '';
}
}

$str = StrFormat_F10::encode("旅游");
print_r($str . "\n");