[b]1 求长度，最基本的[/b] $text = "sunny day"; $count = strlen($text); // $count = 9 [b]2 字符串截取 [/b]截取前多少个字符 $article = "BREAKING NEWS: In ultimate irony, man bites dog."; $summary = substr_replace($article, "...", 40); [b]3 算单词数[/b] $article = "BREAKING NEWS: In ultimate irony, man bites dog."; $wordCount = str_word_count($article); // $wordCount = 8 [b]4 将字符串变成HTML的连接 [/b]$url = "W.J. Gilmore, LLC (http://www.1sucai.cn)"; $url = preg_replace("/http://([A-z0-9./-]+)/", "$0", $url); [b]5 去除字符中的HTML字符串 [/b]$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.