How to split a string on the first occurrence of one of multiple substrings in JavaScript?

Question

Given strings

s1 = "abcfoodefbarghi" 

and

s2 = "abcbardefooghi"

How can I split s1 into "abc" and "defbarghi" and s2 into "abc" and "defooghi" That is: split a string into two on the first occurrence of either one of strings "foo" or "bar"

I suppose this could be done with s.split(/regexp/) , but what should this regexp be?

Answer 1

Use a Regular Expression in this way:

var match = s1.match(/^([\S\s]*?)(?:foo|bar)([\S\s]*)$/);
/* If foo or bar is found:
  match[1] contains the first part
  match[2] contains the second part */

Explanation of the RE:

• [\\S\\s]*? matches just enough characters to match the next part of the RE, which is
• (foo|bar) either "foo", or "bar"
• [\\S\\s]* matches the remaining characters

Parentheses around a part of a RE creates a group, so that the grouped match can be referred, while (?:) creates a non-referrable group.

Answer 2

str.replace(/foo|bar/,"\x034").split("\x034")

idea是用特殊的（不可见的）String替换第一个匹配项，然后对该字符串进行拆分。