php strtolower 函数的问题
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problems with strtolower function
提问by Simon
i have some text in foreign language in my page, but when i make it lowercase, it starts to look like this...
我的页面中有一些外语文本，但是当我将其设为小写时，它开始看起来像这样......
$a = "????? ?????????";
echo $b = strtolower($a);
//returns ????? ?????????
i've set <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />could you tell me why?
thanks in advance
我已经设置了<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />你能告诉我为什么吗？提前致谢
回答by SteelBytes
have your tried using mb_strtolower()?
您是否尝试过使用 mb_strtolower()？
回答by reko_t
PHP5 is not UTF-8 compatible, so you still need to resort to the mb extension. I suggest you set the internal encoding of mb to utf-8 and then you can freely use its functions without specifying the charset all the time:
PHP5 不兼容 UTF-8，因此您仍然需要求助于 mb 扩展名。我建议你将mb的内部编码设置为utf-8，然后你就可以自由使用它的功能，而无需一直指定字符集：
mb_internal_encoding('UTF-8');
...
$b = mb_strtolower($a);
echo $b;
回答by khaled_webdev
回答by Kevin
Have you tried
你有没有尝试过
http://www.php.net/manual/en/function.mb-strtolower.php
http://www.php.net/manual/en/function.mb-strtolower.php
mb_strtolower() and specifying the encoding as the second parameter?
mb_strtolower() 并将编码指定为第二个参数？
The examples on that page appear to work.
该页面上的示例似乎有效。
You could also try:
你也可以试试：
$str = mb_strtolower($str, mb_detect_encoding($str));
回答by SWilk
Php by default does not know about utf-8. It assumes any string is ASCII, so it strtolower converts bytes containing codes of uppercase letters A-Z to codes of lowercase a-z. As the UTF-8 non-ascii letters are written with two or more bytes, the strtolower converts each byte separately, and if the byte happens to contain code equal to letters A-Z, it is converted. In the result the sequence is broken, and it no longer represents correct character.
PHP 默认不知道 utf-8。它假定任何字符串都是 ASCII，因此 strtolower 将包含大写字母 AZ 代码的字节转换为小写 az 代码。由于 UTF-8 非 ascii 字母是用两个或更多字节写入的，所以 strtolower 会分别转换每个字节，如果该字节恰好包含等于字母 AZ 的代码，则对其进行转换。结果序列被破坏，不再代表正确的字符。
To change this you need to configure the mbstring extension:
要更改此设置，您需要配置 mbstring 扩展名：
http://www.php.net/manual/en/book.mbstring.php
http://www.php.net/manual/en/book.mbstring.php
to replace strtolower with mb_strtolower or use mb_strtolower direclty. I any case, you need to spend some time to configure the mbstring settings to match your requirements.
用 mb_strtolower 替换 strtolower 或使用 mb_strtolower direclty。无论如何，您需要花一些时间来配置 mbstring 设置以满足您的要求。
回答by Powerlord
Use mb_strtolowerinstead, as strtolower doesn't work on multi-byte characters.
请改用mb_strtolower，因为 strtolower 不适用于多字节字符。
回答by Pekka
strtolower() will perform the conversion in the currently selected locale only.
strtolower() 将仅在当前选定的语言环境中执行转换。
I would try mb_convert_case(). Make sure you explicitly specify an encoding.
我会尝试mb_convert_case()。确保您明确指定编码。
回答by intuited
You will need to set the locale; see the first example at http://ca3.php.net/manual/en/function.strtolower.php
您需要设置语言环境；请参阅http://ca3.php.net/manual/en/function.strtolower.php 上的第一个示例
