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<html>
<head>
<meta charset="UTF-8">
<title></title>
</head>
<body>
<?php
// put your code here 字符串的输出函数echo()
$str = "Hello World";
echo $str;
?>
</body>
</html>
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<?php
// put your code here程序报错后终止继续运行的函数die()
$conn = @mysql_connect("localhost", "root", "root") or die("数据库连接失败！");
?>
</body>
</html>
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<body>
<?php
// put your code here打印函数print_r()
$arr = array('0'=>'PHP',"1"=>array('0'=>'P', '1'=>'H', '2'=>'P'));
print_r($arr);
?>
</body>
</html>
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<?php
// put your code here字符串分割函数explode()
$str = "PHP,JSP,JAVA,C++,HTML";
print_r(explode(",",$str));
?>
</body>
</html>
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<?php
// put your code here数组元素组合成字符串的函数implode()
$arr = array('Hello', 'World!', 'Beautiful', 'Day!');
echo implode(" ", $arr);
?>
</body>
</html>
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<?php
// put your code here预定义字符串转换为HTML实体的函数htmlspecialchars()
$str = "<strong>PHP100.COM</strong>";
echo htmlspecialchars($str);
?>
</body>
</html>
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<?php
// put your code here
$str = "<font color='red'>PHP</font> + <em>Apache</em> + <b>Mysql</b>";
echo strip_tags($str);
echo "<br/>";
echo strip_tags($str, "<font>");
echo "<br/>";
echo strip_tags($str, "<font><em><b>");
?>
</body>
</html>
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<?php
// put your code here去除字符串首尾连续空格的函数
$str = " PHP100 ";
echo strlen($str)."<br>";
echo strlen(ltrim($str))."<br>";
echo strlen(rtrim($str))."<br>";
echo strlen(trim($str));
?>
</body>
</html>
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<?php
// put your code here
echo nl2br("PHP100.COM \n PHP100.NET");
?>
</body>
</html>
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<body>
<?php
// put your code here加密函数MD5
$str = "PHP100.COM";
echo md5($str);
?>
</body>
</html>
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<body>
<?php
// put your code here加密函数sha1()
$str = "PHP100.COM";
echo sha1($str);
?>
</body>
</html>
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<body>
<?php
// put your code here字符串替换函数str_replace()
$str = "baidu.com";
echo str_replace("baidu", "php100", $str);
?>
</body>
</html>
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<?php
// put your code here数字分组格式化函数number_format()
$number = "1234567890";
echo number_format($number);
echo "<br/>";
echo number_format($number,2);
echo "<br/>";
echo number_format($number,2,",",".");
?>
</body>
</html>
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<?php
// put your code here字符串分割函数str_split()
$str = "Hello World";
$arr1 = str_split($str);
$arr2 = str_split($str,3);
print_r($arr1);
print_r($arr2);
?>
</body>
</html>
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<body>
<?php
// put your code here字符串截取函数substr()
echo substr("WWW.PHP100.COM", 4);
?>
</body>
</html>
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<?php
// put your code here
$str = "我是一名PHP程序员";
echo iconv('UTF-8', 'GBK', $str);
echo iconv_substr($str, "2", "2", "UTF-8");
?>
</body>
</html>
The above introduces the PHP string processing function example study notes, including the relevant content. I hope it will be helpful to friends who are interested in PHP tutorials.
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