我在http://deer.org.ua/2009/10/06/1/:上找到了一个解决方案

class Encoding
{
    /**
     * http://deer.org.ua/2009/10/06/1/
     * @param $string
     * @return null
     */
    public static function detect_encoding($string)
    {
        static $list = ['utf-8', 'windows-1251'];

        foreach ($list as $item) {
            try {
                $sample = iconv($item, $item, $string);
            } catch (\Exception $e) {
                continue;
            }
            if (md5($sample) == md5($string)) {
                return $item;
            }
        }
        return null;
    }
}

$content = file_get_contents($file['tmp_name']);
$encoding = Encoding::detect_encoding($content);
if ($encoding != 'utf-8') {
    $result = iconv($encoding, 'utf-8', $content);
} else {
    $result = $content;
}

我认为@是一个糟糕的决定，并对deer.org.ua的解决方案做了一些更改。

如果您将utf8_encode()应用于一个已经UTF-8的字符串，它将返回乱码的UTF-8输出。

我做了一个函数来解决所有这些问题。它被称为Encoding::toUTF8()。

你不需要知道字符串的编码是什么。它可以是Latin1 (ISO 8859-1)、Windows-1252或UTF-8，或者字符串可以是它们的混合。Encoding::toUTF8()将所有内容转换为UTF-8。

我这样做是因为一个服务给了我一个混乱的数据提要，在同一个字符串中混合了UTF-8和Latin1。

用法:

require_once('Encoding.php');
use \ForceUTF8\Encoding;  // It's namespaced now.

$utf8_string = Encoding::toUTF8($utf8_or_latin1_or_mixed_string);

$latin1_string = Encoding::toLatin1($utf8_or_latin1_or_mixed_string);

下载:

https://github.com/neitanod/forceutf8

我还包含了另一个函数Encoding::fixUFT8()，它将修复每个看起来乱码的UTF-8字符串。

用法:

require_once('Encoding.php');
use \ForceUTF8\Encoding;  // It's namespaced now.

$utf8_string = Encoding::fixUTF8($garbled_utf8_string);

例子:

echo Encoding::fixUTF8("Fédération Camerounaise de Football");
echo Encoding::fixUTF8("Fédération Camerounaise de Football");
echo Encoding::fixUTF8("FÃÂédÃÂération Camerounaise de Football");
echo Encoding::fixUTF8("Fédération Camerounaise de Football");

将输出:

Fédération Camerounaise de Football
Fédération Camerounaise de Football
Fédération Camerounaise de Football
Fédération Camerounaise de Football

我在一个名为Encoding的类上将函数(forceeutf8)转换为一系列静态函数。新函数是Encoding::toUTF8()。

整理完PHP脚本后，不要忘记告诉MySQL你要传递的字符集和你想要接收的字符集。

例如:设置为UTF-8

在Latin 1 I/O会话中将UTF-8数据传递给Latin 1表会导致这些讨厌的鸟脚。我每隔一天就会在OsCommerce商店看到这个。后面和第四个似乎是对的。但是phpMyAdmin会显示真相。通过告诉MySQL你正在传递什么字符集，它将为你处理MySQL数据的转换。

如何恢复现有的乱码MySQL数据是另一个问题。：）

检测编码是困难的。

mb_detect_encoding works by guessing, based on a number of candidates that you pass it. In some encodings, certain byte-sequences are invalid, an therefore it can distinguish between various candidates. Unfortunately, there are a lot of encodings, where the same bytes are valid (but different). In these cases, there is no way to determine the encoding; You can implement your own logic to make guesses in these cases. For example, data coming from a Japanese site might be more likely to have a Japanese encoding.

As long as you only deal with Western European languages, the three major encodings to consider are utf-8, iso-8859-1 and cp-1252. Since these are defaults for many platforms, they are also the most likely to be reported wrongly about. Eg. if people use different encodings, they are likely to be frank about it, since else their software would break very often. Therefore, a good strategy is to trust the provider, unless the encoding is reported as one of those three. You should still doublecheck that it is indeed valid, using mb_check_encoding (note that valid is not the same as being - the same input may be valid for many encodings). If it is one of those, you can then use mb_detect_encoding to distinguish between them. Luckily that is fairly deterministic; You just need to use the proper detect-sequence, which is UTF-8,ISO-8859-1,WINDOWS-1252.

一旦检测到编码，就需要将其转换为内部表示(UTF-8是唯一明智的选择)。函数utf8_encode将ISO-8859-1转换为UTF-8，因此它只能用于特定的输入类型。对于其他编码，使用mb_convert_encoding。

你的编码看起来像是用UTF-8编码了两次;也就是说，从其他编码，转换成UTF-8，再转换成UTF-8。就好像您有ISO 8859-1，从ISO 8859-1转换为UTF-8，并将新字符串处理为ISO 8859-1，以便再次转换为UTF-8。

下面是你所做的一些伪代码:

$inputstring = getFromUser();
$utf8string = iconv($current_encoding, 'utf-8', $inputstring);
$flawedstring = iconv($current_encoding, 'utf-8', $utf8string);

你应该试试:

使用mb_detect_encoding()或任何您喜欢使用的方法来检测编码 如果是UTF-8，转换成ISO 8859-1，然后重复步骤1 最后，转换回UTF-8

这是假设在“中间”转换中使用ISO 8859-1。如果您使用的是Windows-1252，则转换为Windows-1252 (latin1)。原始源编码并不重要;你在有缺陷的第二次转换中使用的是。

以下是我对所发生事情的猜测;要用四个字节代替一个扩展的ASCII字节，您几乎没有其他办法。

德语也使用ISO 8859-2和Windows-1250(拉丁语-2)。

从头文件中获取编码并将其转换为UTF-8。

$post_url = 'http://website.domain';

/// Get headers ///////////////////////////////////////////////
function get_headers_curl($url)
{
    $ch = curl_init();

    curl_setopt($ch, CURLOPT_URL,            $url);
    curl_setopt($ch, CURLOPT_HEADER,         true);
    curl_setopt($ch, CURLOPT_NOBODY,         true);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
    curl_setopt($ch, CURLOPT_TIMEOUT,        15);

    $r = curl_exec($ch);
    return $r;
}

$the_header = get_headers_curl($post_url);

/// Check for redirect ////////////////////////////////////////
if (preg_match("/Location:/i", $the_header)) {
    $arr = explode('Location:', $the_header);
    $location = $arr[1];

    $location = explode(chr(10), $location);
    $location = $location[0];

    $the_header = get_headers_curl(trim($location));
}

/// Get charset ///////////////////////////////////////////////
if (preg_match("/charset=/i", $the_header)) {
    $arr = explode('charset=', $the_header);
    $charset = $arr[1];

    $charset = explode(chr(10), $charset);
    $charset = $charset[0];
}

///////////////////////////////////////////////////////////////////
// echo $charset;

if($charset && $charset != 'UTF-8') {
    $html = iconv($charset, "UTF-8", $html);
}