特定字符串的正则表达式不工作

Question

我有一个这样的字符串:

let input  = "Bldg ,32.9,-117.11,Yes,California,Yes,San Diego,,"San Diego, CA",123"

我需要基于逗号("，")分割字符串，但引号中的逗号应该被忽略。我试图应用正则表达式，但在这种情况下，空白值正在消失。

我需要以下输出

["Bldg",
"32.9", 
"-117.11", 
"Yes",
"California",
"Yes",
"San Diego",
"",
"San Diego, CA",
"123"
]

我已经应用了以下regex -/[^",]+|"([^"]*)"/g，但这不起作用。

Answer 1

可以匹配正则表达式

(?<=")[^"]*(?=")|(?<![^,])[^,"]*(?![^,])

演示匹配的结果如下:

["Bldg ", "32.9", "-117.11", "Yes", "California",
"Yes", "San Diego", "", "San Diego, CA", "123"]

---

正则表达式包含以下元素:

(?<=")      positive lookbehind asserts that previous character is a double-quote
[^"]*       match zero or more characters other than double quotes
(?=")       positive lookahead asserts that next character is a double-quote
|           or
(?<![^,])   negative lookbehind asserts that previous character is not a
character other than a double-quote
[^,"]*      match zero or more characters other than commas and double-quotes
(?![^,])    negative lookahead asserts that next character is not a
character other than a double-quote

注意，双引号"否定"后置断言前一个字符不是双引号"以外的字符。相当于断言前一个字符是双引号，或者当前字符位于字符串的开头。类似地，"反向前看"断言下一个字符不是双引号以外的字符;相当于断言下一个字符是双引号，或者当前字符位于字符串的末尾。