<?php //颠倒字串 print("abcdefg 颠倒 "); print(strrev("abcdefg")."<hr>"); //小写字串 print("小写: ".strtolower("Hello World")."<hr>"); //大写字串 print("大写: ".strtoupper("Hello World")."<hr>"); //去空格 $text = " whitespace "; print("\"" . trim($text) . "\""); ?>
原文：https://www.cnblogs.com/tianpan2019/p/10987994.html