csv 等文件转码

<?php


/**
* 把一个文件夹里的文件全部转码 只能转一次 否则全部变乱码
* @param string $filename
*/
function iconv_file($filename, $input_encoding = 'gbk', $output_encoding = 'utf-8') {
if (file_exists($filename)) {
if (is_dir($filename)) {
foreach (glob("$filename/*") as $key => $value) {
iconv_file($value);
}
} else {
$contents_before = file_get_contents($filename);
/*
$encoding = mb_detect_encoding($contents_before,array('CP936','ASCII','GBK','GB2312','UTF-8'));
echo $encoding;exit;

if($encoding=='UTF-8') mb_detect_encoding函数不工作
{
return;
}*/


$contents_after = mb_convert_encoding($contents_before,$output_encoding,$input_encoding);
file_put_contents($filename, $contents_after);
}
} else {
echo '参数错误';
return false;
}
}
iconv_file('mall_exchange_voucher_log.csv','UTF-8','GBK');
?>