php 一种检查文件大小的简便方法

Posted 2021-05-04

<span style="color: #000000; font-weight: bold;">function</span> StringSizeToBytes<span style="color: #66cc66;">&#40;</span><span style="color: #0000ff;">$Size</span><span style="color: #66cc66;">&#41;</span><span style="color: #66cc66;">&#123;</span>
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    <span style="color: #0000ff;">$Unit</span> = <a href="http://www.php.net/strtolower"><span style="color: #000066;">strtolower</span></a><span style="color: #66cc66;">&#40;</span><span style="color: #0000ff;">$Size</span><span style="color: #66cc66;">&#41;</span>;
    <span style="color: #0000ff;">$Unit</span> = <a href="http://www.php.net/preg_replace"><span style="color: #000066;">preg_replace</span></a><span style="color: #66cc66;">&#40;</span><span style="color: #ff0000;">'/[^a-z]/'</span>, <span style="color: #ff0000;">''</span>, <span style="color: #0000ff;">$Unit</span><span style="color: #66cc66;">&#41;</span>;
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    <span style="color: #0000ff;">$Value</span> = <a href="http://www.php.net/intval"><span style="color: #000066;">intval</span></a><span style="color: #66cc66;">&#40;</span><a href="http://www.php.net/preg_replace"><span style="color: #000066;">preg_replace</span></a><span style="color: #66cc66;">&#40;</span><span style="color: #ff0000;">'/[^0-9]/'</span>, <span style="color: #ff0000;">''</span>, <span style="color: #0000ff;">$Size</span><span style="color: #66cc66;">&#41;</span><span style="color: #66cc66;">&#41;</span>;
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    <span style="color: #0000ff;">$Units</span> = <a href="http://www.php.net/array"><span style="color: #000066;">array</span></a><span style="color: #66cc66;">&#40;</span><span style="color: #ff0000;">'b'</span>=&gt;<span style="color: #cc66cc;">0</span>, <span style="color: #ff0000;">'kb'</span>=&gt;<span style="color: #cc66cc;">1</span>, <span style="color: #ff0000;">'mb'</span>=&gt;<span style="color: #cc66cc;">2</span>, <span style="color: #ff0000;">'gb'</span>=&gt;<span style="color: #cc66cc;">3</span>, <span style="color: #ff0000;">'tb'</span>=&gt;<span style="color: #cc66cc;">4</span><span style="color: #66cc66;">&#41;</span>;
    <span style="color: #0000ff;">$Exponent</span> = <a href="http://www.php.net/isset"><span style="color: #000066;">isset</span></a><span style="color: #66cc66;">&#40;</span><span style="color: #0000ff;">$Units</span><span style="color: #66cc66;">&#91;</span><span style="color: #0000ff;">$Unit</span><span style="color: #66cc66;">&#93;</span><span style="color: #66cc66;">&#41;</span> ? <span style="color: #0000ff;">$Units</span><span style="color: #66cc66;">&#91;</span><span style="color: #0000ff;">$Unit</span><span style="color: #66cc66;">&#93;</span> : <span style="color: #cc66cc;">0</span>;
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    <span style="color: #b1b100;">return</span> <span style="color: #66cc66;">&#40;</span><span style="color: #0000ff;">$Value</span> * <a href="http://www.php.net/pow"><span style="color: #000066;">pow</span></a><span style="color: #66cc66;">&#40;</span><span style="color: #cc66cc;">1024</span>, <span style="color: #0000ff;">$Exponent</span><span style="color: #66cc66;">&#41;</span><span style="color: #66cc66;">&#41;</span>;            
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