php读取txt以及乱码问题方案

今天需要做一个txt协议内容直接上传转换文本显示的功能，用php直接读取内容后发现乱码了，完全看不懂。

经过寻找经验，发现了一个比较好的处理方法：

<?php

function read_txt($fileName)
{
    $contents = file_get_contents($fileName);
    //获取文件的编码方式
    $encoding = mb_detect_encoding($contents, array('GB2312', 'GBK', 'UTF-16', 'UCS-2', 'UTF-8', 'BIG5', 'ASCII'));
    $fp = fopen($fileName, "r");//以只读的方式打开文件
    $text = "<div>";
    $num = 0;
    if (!(feof($fp))) {
        $num++;
        $str = trim(fgets($fp));
        if ($encoding != false) {
            //iconv ()将$encoding 转换成“UTF-8”
            $str = iconv($encoding, 'UTF-8', $str);
            if ($str != "" and $str != NULL) {
                $text = $str;
            }
        } else {
            $str = mb_convert_encoding($str, 'UTF-8', 'Unicode');
            if ($str != "" and $str != NULL) {
                $text = $str;
            }
        }
    }
    while (!(feof($fp))) {
        $str = '';
        $str = trim(fgets($fp));
        if ($encoding != false) {
            $str = iconv($encoding, 'UTF-8', $str);
            if ($str != "" and $str != NULL) {
                $text = $text . "<br>" . $str;
            }
        } else {
            $str = mb_convert_encoding($str, 'UTF-8', 'Unicode');
            if ($str != "" and $str != NULL) {
                $text = $text . "<br>" . $str;
            }
        }
    }
    $text .= '</div>';
    return $text;
}

read_txt(__DIR__ . '/xieyi.txt');

效果图如下：