php：用字母作为分隔符将字符串拆分为数组

Question

如何将$str拆分为任何拉丁字母为分隔符的部分？

$str = "     Hello! How are you? How are you   doing?  ";

应该返回一个

数组

$arr  = ("     ", "! ", " ", " ", "? ", " ", " ", "   ", "?  ");

Answer 1

使用正则表达式。拆分1个或多个+字符a-z或A-Z：

$arr = preg_split('/[a-zA-Z]+/', $str);

在字符类[]中添加您想要的任何内容，例如0-9为数字，或'为撇号等...