php - 为什么不能将所有字符从全角字符更改为半角字符？

Question

我想把所有字符从全角字符变成半角字符，写下面的代码来完成这项工作。例如，要更改

中的所有全角字符

 Ｃｏｄｅｂｉｔ.ｃｎ － 聚合小段精华代码 

成半角字符,成

 codebit.cn - 聚合小段精华代码

有两种方法可以达到目的，但都失败了。
所有的php文件都保存为utf-8格式。

方法一:

<?php
    function fulltohalf($str){
    $arr=Array( 
    '０' => '0', '１' => '1', '２' => '2', '３' => '3', '４' => '4',  
    '５' => '5', '６' => '6', '７' => '7', '８' => '8', '９' => '9', 
    'Ａ' => 'A', 'Ｂ' => 'B', 'Ｃ' => 'C', 'Ｄ' => 'D', 'Ｅ' => 'E',  
    'Ｆ' => 'F', 'Ｇ' => 'G', 'Ｈ' => 'H', 'Ｉ' => 'I', 'Ｊ' => 'J', 
    'Ｋ' => 'K', 'Ｌ' => 'L', 'Ｍ' => 'M', 'Ｎ' => 'N', 'Ｏ' => 'O',  
    'Ｐ' => 'P', 'Ｑ' => 'Q', 'Ｒ' => 'R', 'Ｓ' => 'S', 'Ｔ' => 'T', 
    'Ｕ' => 'U', 'Ｖ' => 'V', 'Ｗ' => 'W', 'Ｘ' => 'X', 'Ｙ' => 'Y',  
    'Ｚ' => 'Z', 'ａ' => 'a', 'ｂ' => 'b', 'ｃ' => 'c', 'ｄ' => 'd', 
    'ｅ' => 'e', 'ｆ' => 'f', 'ｇ' => 'g', 'ｈ' => 'h', 'ｉ' => 'i',  
    'ｊ' => 'j', 'ｋ' => 'k', 'ｌ' => 'l', 'ｍ' => 'm', 'ｎ' => 'n', 
    'ｏ' => 'o', 'ｐ' => 'p', 'ｑ' => 'q', 'ｒ' => 'r', 'ｓ' => 's',  
    'ｔ' => 't', 'ｕ' => 'u', 'ｖ' => 'v', 'ｗ' => 'w', 'ｘ' => 'x', 
    'ｙ' => 'y', 'ｚ' => 'z', '－' => '-' 
    ); 

    $new = '';            
    foreach ($str as $char){
        if (isset ($arr[$char]))  
            $new .= $arr[$char];    
        else
            $new .= $arr;    
        }
    return $new;
    }

$str="Ｃｏｄｅｂｉｔ.ｃｎ － 聚合小段精华代码";
echo fulltohalf($str);
?>

错误信息:

方法二:

<?php
function fulltohalf($Str) { 
    $Queue = Array( 
    '０' => '0', '１' => '1', '２' => '2', '３' => '3', '４' => '4',  
    '５' => '5', '６' => '6', '７' => '7', '８' => '8', '９' => '9', 
    'Ａ' => 'A', 'Ｂ' => 'B', 'Ｃ' => 'C', 'Ｄ' => 'D', 'Ｅ' => 'E',  
    'Ｆ' => 'F', 'Ｇ' => 'G', 'Ｈ' => 'H', 'Ｉ' => 'I', 'Ｊ' => 'J', 
    'Ｋ' => 'K', 'Ｌ' => 'L', 'Ｍ' => 'M', 'Ｎ' => 'N', 'Ｏ' => 'O',  
    'Ｐ' => 'P', 'Ｑ' => 'Q', 'Ｒ' => 'R', 'Ｓ' => 'S', 'Ｔ' => 'T', 
    'Ｕ' => 'U', 'Ｖ' => 'V', 'Ｗ' => 'W', 'Ｘ' => 'X', 'Ｙ' => 'Y',  
    'Ｚ' => 'Z', 'ａ' => 'a', 'ｂ' => 'b', 'ｃ' => 'c', 'ｄ' => 'd', 
    'ｅ' => 'e', 'ｆ' => 'f', 'ｇ' => 'g', 'ｈ' => 'h', 'ｉ' => 'i',  
    'ｊ' => 'j', 'ｋ' => 'k', 'ｌ' => 'l', 'ｍ' => 'm', 'ｎ' => 'n', 
    'ｏ' => 'o', 'ｐ' => 'p', 'ｑ' => 'q', 'ｒ' => 'r', 'ｓ' => 's',  
    'ｔ' => 't', 'ｕ' => 'u', 'ｖ' => 'v', 'ｗ' => 'w', 'ｘ' => 'x', 
    'ｙ' => 'y', 'ｚ' => 'z', '－' => '-' 
); 

return preg_replace("/([\xA3][\xB0-\xB9\xC1-\xDA\xE1-\xFA])/e","\$Queue[\\1]", $Str); 

}

$str = "Ｃｏｄｅｂｉｔ.ｃｎ － 聚合小段精华代码"; 
echo $str; 
echo "<br />"; 
echo fulltohalf($str); 
?>

错误信息:

如何修复其中两个？

我解决了方法一的问题，固定代码如下。

<?php
function fulltohalf($str){
$arr=Array( 
'０' => '0', '１' => '1', '２' => '2', '３' => '3', '４' => '4',  
'５' => '5', '６' => '6', '７' => '7', '８' => '8', '９' => '9', 
'Ａ' => 'A', 'Ｂ' => 'B', 'Ｃ' => 'C', 'Ｄ' => 'D', 'Ｅ' => 'E',  
'Ｆ' => 'F', 'Ｇ' => 'G', 'Ｈ' => 'H', 'Ｉ' => 'I', 'Ｊ' => 'J', 
'Ｋ' => 'K', 'Ｌ' => 'L', 'Ｍ' => 'M', 'Ｎ' => 'N', 'Ｏ' => 'O',  
'Ｐ' => 'P', 'Ｑ' => 'Q', 'Ｒ' => 'R', 'Ｓ' => 'S', 'Ｔ' => 'T', 
'Ｕ' => 'U', 'Ｖ' => 'V', 'Ｗ' => 'W', 'Ｘ' => 'X', 'Ｙ' => 'Y',  
'Ｚ' => 'Z', 'ａ' => 'a', 'ｂ' => 'b', 'ｃ' => 'c', 'ｄ' => 'd', 
'ｅ' => 'e', 'ｆ' => 'f', 'ｇ' => 'g', 'ｈ' => 'h', 'ｉ' => 'i',  
'ｊ' => 'j', 'ｋ' => 'k', 'ｌ' => 'l', 'ｍ' => 'm', 'ｎ' => 'n', 
'ｏ' => 'o', 'ｐ' => 'p', 'ｑ' => 'q', 'ｒ' => 'r', 'ｓ' => 's',  
'ｔ' => 't', 'ｕ' => 'u', 'ｖ' => 'v', 'ｗ' => 'w', 'ｘ' => 'x', 
'ｙ' => 'y', 'ｚ' => 'z', '－' => '-' 
); 

$new = '';
preg_match_all('/./u', $str, $results);
$str=$results[0];            
foreach ($str as $char){
    if (isset ($arr[$char]))  
        $new .= $arr[$char];    
    else
        $new .= $char;   
    }
return $new;
}

echo fulltohalf("Ｃｏｄｅｂｉｔ.ｃｎ － 聚合小段精华代码");
?>

Answer 1

一行代码:

$str="Ｃｏｄｅｂｉｔ.ｃｎ － 聚合小段精华代码";
$str = mb_convert_kana($str, "rnaskhc", 'UTF-8');
echo $str;

和

Ｃｏｄｅｂｉｔ.ｃｎ － 聚合小段精华代码

成为

Codebit.cn - 聚合小段精华代码

并且您可以保留字母的大小写作为奖励。

引用:http://php.net/mb_convert_kana