以一种简单的方式使用php regexp，是否可以修改字符串以在单词后面的句点后面添加空格，而不是在前面和后面都有数字（如1.00）的句点后面？我还需要它忽略单字母缩写，如N.Y.
String.Looks like this.With an amount of 1.00 and references N.Y.
需要更改为…
String. Looks like this. With an amount of 1.00 and references N.Y.
当然，这应该允许字符串中有多个实例。。。
$text = preg_replace('/('.)([[:alpha:]]{2,})/', '$1 $2', $text);
您可以使用以下正则表达式：
/((?<=[A-Za-z0-9])'.(?=[A-Za-z]{2})|(?<=[A-Za-z]{2})'.(?=[A-Za-z0-9]))/
替换字符串为'. '。
注意，上面的regex要求在句号.的一侧至少有一个字母字符，而在另一侧则要求有字母数字字符。
测试字符串：
"String.Looks like this.With an amount of 1.00 and references N.Y.Mr.NoOne.30% replaced.no 50.Don't know."
输出：
"String. Looks like this. With an amount of 1.00 and references N.Y. Mr. NoOne. 30% replaced. no 50. Don't know."