例子
<!DOCTYPE html> <html> <body> <?php $str = "Hello World!"; echo $str . "<br>"; echo trim($str,"Hed!"); ?> </body> </html>
输出
Hello World! llo Worl
echo trim(" Hed! ");
Hed!
参考：
https://www.w3school.com.cn/php/func_string_trim.asp