如何解决php fgets读取文件乱码的问题

<?php 
  $file = fopen("1303275.txt","r");//只读方式打开文本文件 
  while(! feof($file))//当文件不结束 
  { 
      $line=fgets($file);//读一行到$line变量 
      echo $line."<br />"; 
  }  
  fclose($file);//关闭文本文件 
 
?>

/* 
@params $str 输入字符 $type 所需获取编码 
@author 长行 
*/ 
function autoiconv($str,$type = "gb2312//ignore"){ 
 
$utf32_big_endian_bom = chr(0x00) . chr(0x00) . chr(0xfe) . chr(0xff); 
$utf32_little_endian_bom = chr(0xff) . chr(0xfe) . chr(0x00) . chr(0x00); 
$utf16_big_endian_bom = chr(0xfe) . chr(0xff); 
$utf16_little_endian_bom = chr(0xff) . chr(0xfe); 
$utf8_bom = chr(0xef) . chr(0xbb) . chr(0xbf); 
 
$first2 = substr($str, 0, 2); 
$first3 = substr($str, 0, 3); 
$first4 = substr($str, 0, 3); 
 
if ($first3 == $utf8_bom) $icon = 'utf-8'; 
elseif ($first4 == $utf32_big_endian_bom) $icon = 'utf-32be'; 
elseif ($first4 == $utf32_little_endian_bom) $icon = 'utf-32le'; 
elseif ($first2 == $utf16_big_endian_bom) $icon = 'utf-16be'; 
elseif ($first2 == $utf16_little_endian_bom) $icon = 'utf-16le'; 
else { $icon = 'ascii'; return $str;} 
 
return iconv($icon,$type,$str); 
 
}