案例：php案例     状态：不可编辑再运行    进入竖版
 运行结果　
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<!DOCTYPE html>
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<html>
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<body>
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​
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<?php
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$str = "PHP is pretty fun!!";
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$strArray = count_chars($str,1);
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​
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foreach ($strArray as $key=>$value)
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    {
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    echo "字符 <b>'".chr($key)."'</b> 被找到 $value 次。<br>";
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    }
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?>
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​
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</body>
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</html>
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​
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​
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