PHP 获取中英文混合字符串长度

通常情况下要想掌握一个字符串变量的长度[一般掌握其字数],自然想到 strlen

|——

$str = 'string';

echo strlen($str); //6

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|——

$str = "方言";

echo strlen($str);//6

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问题来了，明明是两个字的怎么会得到6的结果：在PHP自带的函数中，strlen及mb_strlen都是通过计算字符串所占字节数来计算长度的，在不同的编码情况下，中文所占的字节数是不同的。在GBK/GB2312下，中文字符占2个字节，而在UTF-8下，中文字符占3个字节。

[我们不需要掌握字节数，没有意义，只要掌握字数就行]

|——

$str = '你好，世界！';

echo strlen($str);    // GBK或GB2312下输出12，UTF-8下输出18

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Wordpress 的代码可以借鉴

|——

$str = 'Hello，世界！';

preg_match_all('/./us', $str, $match);

echo count($match[0]);    // 输出9

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思路是用正则将字符串切割成单个字符，直接获取匹配到的结果，得到结果。

但以上代码在UTF-8编码下并不能处理GBK/GB2312的中文字符串，因为GBK/GB2312的中文字符会被识别为两个字符而计算出来的中文字符数量会翻倍。

|——

$tmp = @iconv('gbk', 'utf-8', $str);

if(!empty($tmp)){

    $str = $tmp;

}

preg_match_all('/./us', $str, $match);

echo count($match[0]);

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这样可以做到utf-8 和gbk环境下的兼容，但是一般日常我们都是掌握编码环境的[utf-8];

这样我们获取字符变量的字数就用：

|——

int iconv_strlen ( string $str [, string $charset = ini_get("iconv.internal_encoding") ] );

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参考：

http://www.clanfei.com/2012/12/1671.html