字边界？或者是其他东西 ？ [英] Word boundary ? or something else ?

问题描述

大家好，

我尝试构建模式以匹配"sign-value-unit"字符串，这些模式必须是动态的，根据文化。正文和负号以及小数分隔符在文化中指定，我们定义单位是"所有不是数字或正号或负号或小数分隔符（或cr和lf）"

I'm try to build patterns to match strings that are "sign-value-unit", these patterns must be dynamic according to a Culture. The positive and negative signs and the decimal separator are specified in the culture, and we defined that the unit is "everything that is not a digit or the positive or negative sign or decimal seperator (or cr and lf)"

当文化为正号和负号分别指定为"+"和" - "而小数分隔符为"。"时，我的最终模式如下所示：
（？< sign> [ \ + - ]）？\？（？< value>（？：\d +（\。\\\ *）？）|（？：\。\ d +））\？（？ < unit> [^ - \ + \.\r\\\
\0x00] +）？

如您所见，每个部分之间允许有一个可选空间。此模式匹配并捕获以下字符串：" + 1.2unit"或"+1.2单位"

When the culture specify as '+' and '-' for positive and negative signs and '.' for decimal separator my final pattern looks like this:
(?<sign>[\+-])?\ ?(?<value>(?:\d+(\.\d*)?)|(?:\.\d+))\ ?(?<unit>[^-\+\.\r\n\0x00]+)?

As you can see, an optional space is allowed between each part.
This pattern matches and capture the following strings : "+1.2unit" or "+1.2 unit"

当符号和/或小数分隔符是单词而不是字符时，会出现问题。让我们拥有"加号"和"减"作为标志和"点"作为辞职者。我的模式的单位部分现在看起来如下：

（？< unit> \b （？:(？！\d |（？：Plus） ）|（？：减号）|（？：点）| \ r | \ n | \0x00）。）*）？

My problem occurs when the signs and/or decimal separator are words instead of characters. Let's ay that I have "Plus" and "Minus" as signs and "Point" as serator. The unit part of my pattern that now looks like this:

(?<unit>\b (?:(?!\d|(?:Plus)|(?:Minus)|(?:Point)|\r|\n|\0x00).)*)?

如果我不使用单词边界锚（粗体），我的单位模式捕获" oint "在" 1Point2单位"中这不是我的期望。
如果我使用单词boundary，它适用于" 1Point2 Unit "但如果价值和单位之间没有空格，则无法捕获单位：" 1Point2Unit "

If I do not use the word boundary anchor (in bold), my unit pattern captures "oint " in "1Point2 Unit " that is not what I expect.
If I use the word boundary, it works fine for "1Point2 Unit " but fails to capture the unit if there is no space between value and unit : "1Point2Unit "

我认为我承认为什么我的模式未能捕获，但我不知道如何修改它，成功。我是完全错误的，试图通过使用\b来做到这一点。有人可以帮助我吗？

乔乔

I think that I undertand why this my pattern fails to capture, but I cleary don't know how I can modify it, to succeed. My be I'm totally wrong trying to do this by using \b.
Could someone, please, help me ?


Jojo

推荐答案

查看正则表达式如果条件。这样你可以做一个 prememtive 查看数据，如果它是文本，做一件事，否则做其他事情。我在我的博客上讨论它：

正则表达式和If条件

请注意我在博客上的示例中我匹配if处理中的不同组名。没有理由不在if的不同部分找到类似的匹配组名称。

HTH

Check out the regex if conditonal . That way you can do a prememtive look at the data, if it is text, do one thing, otherwise do something else. I discuss it on my blog:

Regular Expressions and the If Conditional

Note in my example on the blog I match to different group names in the if processing. There is no reason not to have similar match group names though found in different parts of the if.

HTH

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