<?php 
//A字符 
$str=(pack("A*", "中国")); 
echo $str,"=",strlen($str),"字节\n"; 
getAscill($str); 
//H字符 
$str=(pack("H*", "fffe")); 
echo $str,"=",strlen($str),"字节\n"; 
getAscill($str); 
//C字符 
$str=(pack("C*", "55","56","57")); 
echo $str,"=",strlen($str),"字节\n"; 
getAscill($str); 

//i字符 短整形 32位 4个字节 64位8个字节 
$str=(pack("i", "100")); 
echo $str,"=",strlen($str),"字节\n"; 
getAscill($str); 

//s字符 短整形 2个字节 
$str=(pack("s", "100")); 
echo $str,"=",strlen($str),"字节\n"; 
getAscill($str); 

//l字符 长整形 4个字节 
$str=(pack("l", "100")); 
echo $str,"=",strlen($str),"字节\n"; 
getAscill($str); 

//f字符 单精度浮点 4个字节 
$str=(pack("f", "100")); 
echo $str,"=",strlen($str),"字节\n"; 
getAscill($str); 

//d字符 双精度浮点 8个字节 
$str=(pack("d", "100")); 
echo $str,"=",strlen($str),"字节\n"; 
getAscill($str); 

function getAscill($str) 
{ 
$arr=str_split($str); 
foreach ($arr as $v) 
{ 
echo $v,"=",ord($v),"\n"; 
} 
echo "=============\r\n\r\n"; 
} 

file_put_contents("c:/1.txt",$stream);//将流保存起来便于下面读取 

function parkByArr($arr) 
{ 
$atArr=array(); 
foreach ($arr as $k=>$v) 
{ 
$atArr[]=pack($v[0],$v[1]); 
} 
return $atArr; 
} 
function getAscill($str) 
{ 
$arr=str_split($str); 
foreach ($arr as $v) 
{ 
echo $v,"=",ord($v),"\n"; 
} 
} 

<?php 
$code=array( 
"username"=>array("A20"), 
"pass"=>array("A10"), 
"age"=>array("C"), 
"birthday"=>array("I"), 
"email"=>array("A50")); 
$stream=file_get_contents("c:/1.txt"); 
var_dump(parkByArr($stream,$code)); 
function parkByArr($str,$code) 
{ 
$Arr=explode("\0",$str); 
$atArr=array(); 
$i=0; 
foreach ($code as $k=>$v) 
{ 
$atArr[$k]=unpack($v[0],$Arr[$i]); 
$i++; 
} 
return $atArr; 
}