PHP将8字节ASCII码数据表示转化成浮点数值

   //将8字节表示的ASCII字符串转换成浮点数值function conver($str){$c=strtolower($str);//strtower()可以将字符串全部变小写$d=str_prefix($c,$n=1,$char='0x');//给字符串前面添加0x$val=hexdec($d);//将16进制转化成10进制$b = unpack('f', pack('N', $val));//转化浮点数值//echo $b[1];return $b[1];}    //给字符串前面添加指定字符function str_prefix($str, $n=1, $char=" "){for ($x=0;$x<$n;$x++){$str = $char.$str;}  return $str;}