为什么 mb_convert_encoding 返回 false？

Question

这是我的代码：

static function CreateHash($password) {
    $upass = mb_convert_encoding($password,'UCS-2LE','auto');

    // note I have tried calling the following function to get the 
    // encoding type of $password and it returns ASCII
    // $encoding = mb_detect_encoding($password);
}

如果我用 $password = "abc123!" 调用上面的函数，mb_convert_encoding returns false.

Answer 1

根据PHP Manual

"auto" is expanded to "ASCII,JIS,UTF-8,EUC-JP,SJIS"

但就我而言，它无法正常工作。如果我尝试使用以下代码而不是 'auto'，我会得到预期的结果：

$upass = mb_convert_encoding($password, 'UCS-2LE', "ASCII,JIS,UTF-8,EUC-JP,SJIS");

为什么 mb_convert_encoding 返回 false？

Why is mb_convert_encoding returning false?

php

encoding