复制代码 代码如下:
iconv('GBK', 'UTF-8//IGNORE', ''); // 将字符串由 GBK 编码转换为 UTF-8 编码
但 iconv 只能解决编码预先知道的情况,如果字符串编码未知,则需要先探测其编码,这时可能会用到 mb_string 扩展库:
复制代码 代码如下:
mb_detect_encoding('');
可是 mb_detect_encoding 存在一个硬伤,经常出现判断不准确的情况。或许这样就可以解决:
复制代码 代码如下:
// 使用 iconv 转换并判断是否等值,效率不高
function is_utf8 ($str) {
if ($str === iconv('UTF-8', 'UTF-8//IGNORE', $str)) {
return 'UTF-8';
}
}
// 多种编码的情况
function detect_encoding ($str) {
foreach (array('GBK', 'UTF-8') as $v) {
if ($str === iconv($v, $v . '//IGNORE', $str)) {
return $v;
}
}
}
通过以上方式得到字符串编码信息后,就可以利用 iconv 或 mb_convert_encoding 来转换编码了。

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