Home Backend Development PHP Tutorial Detailed explanation of how PHP converts full-width symbols in text to half-width

Detailed explanation of how PHP converts full-width symbols in text to half-width

Jan 03, 2018 am 09:23 AM
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PHP如何将文本中的全角符号转为半角?本文将分享一个封装好的转换方法,大家可以参考一下。希望对大家有所帮助。

将一个字串中含有全角的数字字符、字母、空格或'%+-()'字符转换为相应半角字符

/** 
* 将一个字串中含有全角的数字字符、字母、空格或'%+-()'字符转换为相应半角字符 
* @access public 
* @param string $str 待转换字串 
* @return string $str 处理后字串 
*/ 
function make_semiangle($str) 
{ 
    $arr = array(&#39;0&#39; => &#39;0&#39;, &#39;1&#39; => &#39;1&#39;, &#39;2&#39; => &#39;2&#39;, &#39;3&#39; => &#39;3&#39;, &#39;4&#39; => &#39;4&#39;,&#39;5&#39; => &#39;5&#39;, &#39;6&#39; => &#39;6&#39;, &#39;7&#39; => &#39;7&#39;, &#39;8&#39; => &#39;8&#39;, &#39;9&#39; => &#39;9&#39;, &#39;A&#39; => &#39;A&#39;, &#39;B&#39; => &#39;B&#39;, &#39;C&#39; => &#39;C&#39;, &#39;D&#39; => &#39;D&#39;, &#39;E&#39; => &#39;E&#39;,&#39;F&#39; => &#39;F&#39;, &#39;G&#39; => &#39;G&#39;, &#39;H&#39; => &#39;H&#39;, &#39;I&#39; => &#39;I&#39;, &#39;J&#39; => &#39;J&#39;, &#39;K&#39; => &#39;K&#39;, &#39;L&#39; => &#39;L&#39;, &#39;M&#39; => &#39;M&#39;, &#39;N&#39; => &#39;N&#39;, &#39;O&#39; => &#39;O&#39;,&#39;P&#39; => &#39;P&#39;, &#39;Q&#39; => &#39;Q&#39;, &#39;R&#39; => &#39;R&#39;, &#39;S&#39; => &#39;S&#39;, &#39;T&#39; => &#39;T&#39;,U&#39; => &#39;U&#39;, &#39;V&#39; => &#39;V&#39;, &#39;W&#39; => &#39;W&#39;, &#39;X&#39; => &#39;X&#39;, &#39;Y&#39; => &#39;Y&#39;,&#39;Z&#39; => &#39;Z&#39;, &#39;a&#39; => &#39;a&#39;, &#39;b&#39; => &#39;b&#39;, &#39;c&#39; => &#39;c&#39;, &#39;d&#39; => &#39;d&#39;,&#39;e&#39; => &#39;e&#39;, &#39;f&#39; => &#39;f&#39;, &#39;g&#39; => &#39;g&#39;, &#39;h&#39; => &#39;h&#39;, &#39;i&#39; => &#39;i&#39;,&#39;j&#39; => &#39;j&#39;, &#39;k&#39; => &#39;k&#39;, &#39;l&#39; => &#39;l&#39;, &#39;m&#39; => &#39;m&#39;, &#39;n&#39; => &#39;n&#39;,&#39;o&#39; => &#39;o&#39;, &#39;p&#39; => &#39;p&#39;, &#39;q&#39; => &#39;q&#39;, &#39;r&#39; => &#39;r&#39;, &#39;s&#39; => &#39;s&#39;, &#39;t&#39; => &#39;t&#39;, &#39;u&#39; => &#39;u&#39;, &#39;v&#39; => &#39;v&#39;, &#39;w&#39; => &#39;w&#39;, &#39;x&#39; => &#39;x&#39;, &#39;y&#39; => &#39;y&#39;, &#39;z&#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; => &#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; => &#39;"&#39;, &#39;&#39;&#39; => &#39;`&#39;, &#39;‘&#39; => &#39;`&#39;, &#39;|&#39; => &#39;|&#39;, &#39;〃&#39; => &#39;"&#39;,&#39; &#39; => &#39; &#39;); 
    return strtr($str, $arr); 
}
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<?php 
    $str = "0123ABCDFWS\",.?<>{}[]*&^%#@!~()+-|:;"; 
    echo "$str"; 
    echo "<br />"; 
    $str = preg_replace(&#39;/\xa3([\xa1-\xfe])/e&#39;, &#39;chr(ord(\1)-0x80)&#39;, $str); 
    echo $str; 
?>
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另外为大家分享一个函数
在许多收集用户信息的表单里,期望用户输入的是半角字符,但是无论你如何强调,如何提醒,还是会有粗心的用户提交全角数据,其实,在一些新手眼中,全角和半角根本就没有区别,甚至他们会觉得:我提交的明明是正确的信息,为什么会提示错误呢?

实际上,全角和半角有一一对应关系,而大多数用户并非故意输入错误的信息,所以,我们可以通过程序来避免这种情况的发生,最多,可以在转换后给用户一个确认的机会,这样,或许能够给用户一个更好的体验。

下面介绍一个函数,实现字符 半角 和 全角 之间的互转

<?php
header("Content-type: text/html; charset=utf-8");
// 第一个参数:传入要转换的字符串
// 第二个参数:取0,半角转全角;取1,全角到半角
function SBC_DBC($str, $args2) {
    $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, $str);  // 半角到全角
    } else if ($args2 == 1) {
        return str_replace($DBC, $SBC, $str);  // 全角到半角
    } else {
        return false;
    }
}
$str1 = "http://";
$str2 = "http://";
echo "半角 转 全角:<br />";
echo $str1 . &#39; -> &#39; . SBC_DBC($str1, 0);
echo "<br /><br />全角 转 半角:<br />";
echo $str2 . &#39; -> &#39; . SBC_DBC($str2, 1);
?>
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