php 读取二进制文件

$file_pointer = fopen($file, "r");
$file_read = fread($file_pointer, filesize($file));
//$file_read = fread($file_pointer, 1);
fclose($file_pointer);
$string = asc2bin(($file_read));//转换为二进制流 111111110000000010101010
$string = bin2hex($file_read);//十六进制字符串 8f6d3b

//转换为二进制流
function asc2bin($temp)
{
    $len = strlen($temp);
    for ($i = 0; $i < $len; $i++) {
        $data .= sprintf('%08b', ord(substr($temp, $i, 1)));
    }
    return $data;
}