java - 用于在每个字符处拆分但将数字保持在一起的正则表达式

Question

我正在寻找一个正则表达式来拆分字符串，如下所示:

String input = "x^(24-3x)";
String[] signs = input.split("regex here");
for (int i = 0; i < signs.length; i++) { System.out.println(sings[i]); }

输出结果为:

"x", "^", "(", "24", "-", "3", "x", ")"

字符串在每个字符处被拆分。但是，如果数字彼此相邻，则它们应保持在一个字符串中。

Answer 1

您可以使用这个基于环视的正则表达式:

String[] signs = input.split("(?<!^)(?=\\D)|(?<=\\D)");

RegEx Demo

正则表达式分解

(?<!^)(?=\\D)  # assert if next char is non-digit and we're not at start
|              # regex alternation
(?<=\\D)       # assert if previous character is a non-digit