@minionorg/share
Version:
21 lines (20 loc) • 796 B
TypeScript
/**
* 获取第一次出现分隔符之前的子字符串,不返回分隔符
*
* @param {string} str 从中获取子字符串的字符串可能为null
* @param {(string | number)} separator 要搜索的字符串可能为null
* @return {string} 第一次出现分隔符之前的子字符串
* @example
* substringBefore(null) = null
* substringBefore('') = ''
* substringBefore('abc', 'a') = ''
* substringBefore(' bc', 32) = ''
* substringBefore('abcba', 'b') = 'a'
* substringBefore('abc', 'c') = 'ab'
* substringBefore('a', 'a') = ''
* substringBefore('a', 'z') = 'a'
* substringBefore('abc', '') = ''
* substringBefore('abc', null) = ''
*/
declare function substringBefore(str: string, separator?: string | number): string;
export default substringBefore;