1 求长度，最基本的

$text = "sunny day";

$count = strlen($text); // $count = 9

2 字符串截取

截取前多少个字符

$article = "BREAKING NEWS: In ultimate irony, man bites dog."; $summary = substr_replace($article, "...", 40);

3 算单词数

$article = "BREAKING NEWS: In ultimate irony, man bites dog."; $wordCount = str_word_count($article);

// $wordCount = 8

4 将字符串变成HTML的连接

$url = "W.J. Gilmore, LLC (http://www.jb51.net)";

$url = preg_replace("/http://([A-z0-9./-]+)/", "$0", $url);

5 去除字符中的HTML字符串

$text = strip_tags($input, "

");

6 nl2br:

$comment = nl2br($comment);

变成带HTML格式

7 Wordwrap

限制每行字数

$speech = "Four score and seven years ago our fathers brought forth, upon this continent, a new nation, conceived in Liberty, and dedicated to the proposition that all men are created equal.";

echo wordwrap($speech, 30);

输出：

Four score and seven years ago our fathers brought forth, upon this continent, a new nation, conceived in Liberty, and dedicated to the proposition that all men are created equal.