php如何实现全角符号转半角

php实现全角符号转半角的方法：首先创建一个PHP示例文件；然后定义一个“SBC_DBC($str,$args2=1) {...}”方法；最后通过“str_replace($DBC,$SBC,$str);”方式实现全角转半角即可。

本文操作环境：windows7系统、PHP7.1版，DELL G3电脑

PHP 全角和半角转换函数

代码如下：

<?PHP
function SBC_DBC($str,$args2=1) { //半角和全角转换函数，第二个参数如果是0,则是半角到全角；如果是1，则是全角到半角
$DBC = Array(
&#39;０&#39; , &#39;１&#39; , &#39;２&#39; , &#39;３&#39; , &#39;４&#39; , 
&#39;５&#39; , &#39;６&#39; , &#39;７&#39; , &#39;８&#39; , &#39;９&#39; ,
&#39;Ａ&#39; , &#39;Ｂ&#39; , &#39;Ｃ&#39; , &#39;Ｄ&#39; , &#39;Ｅ&#39; , 
&#39;Ｆ&#39; , &#39;Ｇ&#39; , &#39;Ｈ&#39; , &#39;Ｉ&#39; , &#39;Ｊ&#39; ,
&#39;Ｋ&#39; , &#39;Ｌ&#39; , &#39;Ｍ&#39; , &#39;Ｎ&#39; , &#39;Ｏ&#39; , 
&#39;Ｐ&#39; , &#39;Ｑ&#39; , &#39;Ｒ&#39; , &#39;Ｓ&#39; , &#39;Ｔ&#39; ,
&#39;Ｕ&#39; , &#39;Ｖ&#39; , &#39;Ｗ&#39; , &#39;Ｘ&#39; , &#39;Ｙ&#39; , 
&#39;Ｚ&#39; , &#39;ａ&#39; , &#39;ｂ&#39; , &#39;ｃ&#39; , &#39;ｄ&#39; ,
&#39;ｅ&#39; , &#39;ｆ&#39; , &#39;ｇ&#39; , &#39;ｈ&#39; , &#39;ｉ&#39; , 
&#39;ｊ&#39; , &#39;ｋ&#39; , &#39;ｌ&#39; , &#39;ｍ&#39; , &#39;ｎ&#39; ,
&#39;ｏ&#39; , &#39;ｐ&#39; , &#39;ｑ&#39; , &#39;ｒ&#39; , &#39;ｓ&#39; , 
&#39;ｔ&#39; , &#39;ｕ&#39; , &#39;ｖ&#39; , &#39;ｗ&#39; , &#39;ｘ&#39; ,
&#39;ｙ&#39; , &#39;ｚ&#39; , &#39;－&#39; , &#39;　&#39;  , &#39;：&#39; ,
&#39;．&#39; , &#39;，&#39; , &#39;／&#39; , &#39;％&#39; , &#39;＃&#39; ,
&#39;！&#39; , &#39;＠&#39; , &#39;＆&#39; , &#39;（&#39; , &#39;）&#39; ,
&#39;＜&#39; , &#39;＞&#39; , &#39;＂&#39; , &#39;＇&#39; , &#39;？&#39; ,
&#39;［&#39; , &#39;］&#39; , &#39;｛&#39; , &#39;｝&#39; , &#39;＼&#39; ,
&#39;｜&#39; , &#39;＋&#39; , &#39;＝&#39; , &#39;＿&#39; , &#39;＾&#39; ,
&#39;￥&#39; , &#39;￣&#39; , &#39;｀&#39;
);
$SBC = Array( //半角
&#39;0&#39;, &#39;1&#39;, &#39;2&#39;, &#39;3&#39;, &#39;4&#39;, 
&#39;5&#39;, &#39;6&#39;, &#39;7&#39;, &#39;8&#39;, &#39;9&#39;,
&#39;A&#39;, &#39;B&#39;, &#39;C&#39;, &#39;D&#39;, &#39;E&#39;, 
&#39;F&#39;, &#39;G&#39;, &#39;H&#39;, &#39;I&#39;, &#39;J&#39;,
&#39;K&#39;, &#39;L&#39;, &#39;M&#39;, &#39;N&#39;, &#39;O&#39;, 
&#39;P&#39;, &#39;Q&#39;, &#39;R&#39;, &#39;S&#39;, &#39;T&#39;,
&#39;U&#39;, &#39;V&#39;, &#39;W&#39;, &#39;X&#39;, &#39;Y&#39;, 
&#39;Z&#39;, &#39;a&#39;, &#39;b&#39;, &#39;c&#39;, &#39;d&#39;,
&#39;e&#39;, &#39;f&#39;, &#39;g&#39;, &#39;h&#39;, &#39;i&#39;, 
&#39;j&#39;, &#39;k&#39;, &#39;l&#39;, &#39;m&#39;, &#39;n&#39;,
&#39;o&#39;, &#39;p&#39;, &#39;q&#39;, &#39;r&#39;, &#39;s&#39;, 
&#39;t&#39;, &#39;u&#39;, &#39;v&#39;, &#39;w&#39;, &#39;x&#39;,
&#39;y&#39;, &#39;z&#39;, &#39;-&#39;, &#39; &#39;, &#39;:&#39;,
&#39;.&#39;, &#39;,&#39;, &#39;/&#39;, &#39;%&#39;, &#39;#&#39;,
&#39;!&#39;, &#39;@&#39;, &#39;&&#39;, &#39;(&#39;, &#39;)&#39;,
&#39;<&#39;, &#39;>&#39;, &#39;"&#39;, &#39;\&#39;&#39;,&#39;?&#39;,
&#39;[&#39;, &#39;]&#39;, &#39;{&#39;, &#39;}&#39;, &#39;\\&#39;,
&#39;|&#39;, &#39;+&#39;, &#39;=&#39;, &#39;_&#39;, &#39;^&#39;,
&#39;$&#39;, &#39;~&#39;, &#39;`&#39;
);
if($args2==0)
return str_replace($SBC,$DBC,$str);  //半角到全角
if($args2==1)
return str_replace($DBC,$SBC,$str);  //全角到半角
else
return false;
}
/*
$str = "alskdf";
echo $str;
echo "<br>";
echo SBC_DBC($str,0);
echo SBC_DBC($str,1);
*/
?>

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