根据每次确定性有限自动机达到最终状态来分割字符串？
我有一个问题，有一个可以通过迭代解决的解决方案，但我想知道是否有一个使用正则表达式和 split() 的更优雅的解决方案
我有一个字符串（excel 正在使用它）剪贴板），本质上是逗号分隔的。需要注意的是，当单元格值包含逗号时，整个单元格都会用引号引起来（大概是为了转义该字符串中的逗号）。示例字符串如下：
123,12,"12,345",834,54,"1,111","98,273","1,923,002",23,"1,243"
现在，我想优雅地将这个字符串拆分为单独的单元格，但问题是我不能使用以逗号作为分隔符的普通拆分表达式，因为它会分割值中包含逗号的单元格。看待这个问题的另一种方式是，如果逗号前面有偶数个引号，我可以ONLY在逗号上拆分。
这很容易用循环解决，但我想知道是否有正则表达式.split 函数能够捕获此逻辑。为了解决这个问题，我为逻辑构建了确定性有限自动机（DFA）。
现在的问题简化为以下内容：有没有办法分割这个字符串，以便一个新的数组元素（每次在 DFA 中达到最终状态（此处为状态 4）时都会生成（对应于 /s）？
I have a problem which has an solution that can be solved by iteration, but I'm wondering if there's a more elegant solution using regular expressions and split()
I have a string (which excel is putting on the clipboard), which is, in essence, comma delimited. The caveat is that when the cell values contain a comma, the whole cell is surrounded with quotation marks (presumably to escape the commas within that string). An example string is as follows:
123,12,"12,345",834,54,"1,111","98,273","1,923,002",23,"1,243"
Now, I want to elegantly split this string into individual cells, but the catch is I cannot use a normal split expression with comma as a delimiter, because it will divide cells that contain a comma in their value. Another way of looking at this problem, is that I can ONLY split on a comma if there is an EVEN number of quotation marks preceding the comma.
This is easy to solve with a loop, but I'm wondering if there's a regular expression.split function capable of capturing this logic. In an attempt to solve this problem, I constructed the Deterministic Finite Automata (DFA) for the logic.
The question now is reduced to the following: is there a way to split this string such that a new array element (corresponding to /s) is produced each time the final state (state 4 here) is reached in a DFA?
如果你对这篇内容有疑问，欢迎到本站社区发帖提问 参与讨论，获取更多帮助，或者扫码二维码加入 Web 技术交流群。
绑定邮箱获取回复消息
由于您还没有绑定你的真实邮箱，如果其他用户或者作者回复了您的评论，将不能在第一时间通知您！
发布评论
评论（2）
使用正则表达式（未转义）：
(?:(?:"[^"]*")|(?:[^,]*))使用它并调用 Regex.Matches() ，即 . NET 或其他平台中的类似内容，
您可以将上面的内容进一步扩展为：
^(?:(?:"(?[^"]*)")|(?; [^,]*))(?:,(?:(?:"(?<值>[^"]*)")|(?<值>[^,]*)))*$< /code> 这将一次性解析整个字符串，但您需要命名组和每组的多重捕获才能正常工作（.NET 支持）。
Using regex (unescaped):
(?:(?:"[^"]*")|(?:[^,]*))Use that and call Regex.Matches() which is .NET, or its analog in other platforms.
You could further expand the above to this:
^(?:(?:"(?<Value>[^"]*)")|(?<Value>[^,]*))(?:,(?:(?:"(?<Value>[^"]*)")|(?<Value>[^,]*)))*$This will parse the whole string in 1 shot, but you need named groups and multi-capture per group for this to work (.NET supports it).
合格的逗号后还带有偶数个引号，并且 VBScript 确实支持前视。尝试对此进行拆分：
Eligible commas are also followed by an even number of quotes, and VBScript does support lookaheads. Try splitting on this: