这段php代码怎么写成能输出的结果和js一样？
下面是我自己转成php代码
function na($a) {
if (!$a) return ;
$a = (string)$a;
$h=array(-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,62,-1,-1,-1,63,52,53,54,55,56,57,58,59,60,61,-1,-1,-1,-1,-1,-1,-1,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,-1,-1,-1,-1,-1,-1,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,-1,-1,-1,-1,-1);
$i = strlen($a);
$e=;
for ($f = 0;$f<$i;){
do {$aa=$a[$f++];$c = $h[ord($aa) & 255];}while ($f < $i && -1 == $c);
if (-1 == $c) break;
do {$aa2=$a[$f++];$b = $h[ord($aa2) & 255];} while ($f < $i && -1 == $b);
if (-1 == $b) break;
$e += (string)chr($c 4);
do{ $aa3=$a[$f++];$c=ord($aa3)&255;if(61==$c)return $e;$c=$h[$c];}while($f<$i&&-1==$c);
if (-1 == $c) break;
$e += (string)chr(($b & 15) 2);
do{ $aa4=$a[$f++];$b=ord($aa4)&255; if(61==$b)return $e;$b=$h[$b];}while($f<$i&&-1==$b);
if (-1 == $b) break;
$e += (string)chr(($c &3) << 6 | $b);
}
//echo $e;
return $e;
}

下面是原js代码
function na(a) {
if (!a) return ;
var a = a.tostring(),
c, b, f, i, e, h = [-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 62, -1, -1, -1, 63, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -1, -1, -1, -1, -1, -1, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, -1, -1, -1, -1, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, -1, -1, -1, -1, -1];
i = a.length;
f = 0;
for (e = ; f < i;) {
do c = h[a.charcodeat(f++) & 255]; while (f < i && -1 == c);
if (-1 == c) break;
do b = h[a.charcodeat(f++) & 255]; while (f < i && -1 == b);
if (-1 == b) break;
e += string.fromcharcode(c 4);
do {
c = a.charcodeat(f++) & 255;
if (61 == c) return e;
c = h[c]
} while (f < i && -1 == c);
if (-1 == c) break;
e += string.fromcharcode((b & 15) 2);
do {
b = a.charcodeat(f++) & 255;
if (61 == b) return e;
b = h[b]
} while (f < i && -1 == b);
if (-1 == b) break;
e += string.fromcharcode((c & 3) << 6 | b)
}
return e
}

我用这个字符串做测试：naxrsg4bl7zd0vjf8+jxvnxyuubv1wnlurc=
在php测试结果是：4
但在js里面测试结果是：4?jmail protected] ?q
不知道哪里错误了
------解决思路----------------------
function na($a) {
if (!$a) return ;
$a = $a;
$h = [-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 62, -1, -1, -1, 63, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -1, -1, -1, -1, -1, -1, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, -1, -1, -1, -1, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, -1, -1, -1, -1, -1];
$i = strlen($a);
$f = 0;
for ($e = ; $f < $i;) {
do $c = $h[ord($a{$f++}) & 255]; while ($f < $i && -1 == $c);
if (-1 == $c) break;
do $b = $h[ord($a{$f++}) & 255]; while ($f < $i && -1 == $b);
if (-1 == $b) break;
$e .= chr($c 4);
do {
$c = ord($a{$f++}) & 255;
if (61 == $c) return $e;
$c = $h[$c];
} while ($f < $i && -1 == $c);
if (-1 == $c) break;
$e .= chr(($b & 15) 2);
do {
$b = ord($a{$f++}) & 255;
if (61 == $b) return $e;
$b = $h[$b];
} while ($f < $i && -1 == $b);
if (-1 == $b) break;
$e .= chr(($c & 3) << 6
------解决思路----------------------
$b);
}
return $e;
}