.NET正则表达式空格特殊字符

Question

This pattern is not working sometimes (it works only for the 3rd instance). The pattern is ^\\s*flood\\s{55}\\s+\\w+

I am new to regular expression and I am trying to write a regular expression that captures all the following conditions:

Example 1: flood                 a)
Example 2: flood                 As respects
Example 3: flood                 USD100,000

(it's in a tabular format and there's a lot of space between flood and the next word)

Answer 1

Your expression is saying:

^\\s* The start of the string may have zero or more whitespace characters

flood followed by the string flood

\\s{55} followed by exactly 55 whitespace characters

\\s+\\w+ followed by one or more whitespace characters and then one or more word characters.

If you want a minimum number of whitespace characters, say at least 30, followed by one or more word chraracters, then you could do this:

^\\s*flood\\s{30,}\\w+

Answer 2

Try this:

string input =
@" flood                 a)
   flood                 As respects
   flood                 USD100,000";
string pattern = @"^\s*flood\s+.+$";
MatchCollection matches = Regex.Matches(input, pattern, RegexOptions.Multiline);

Answer 3

If there are a lot of spaces between flood and the next word you could omit \\s{55} which is a quantifier that matches a whitespace character 55 times.

That would leave you with ^\\s*flood\\s+\\w+ which does not yet match all the values at the end because \\w matches a word character but not a whitespace or any of ), .

To match your values you might use a character class and add the characters that you allow to match:

^\\s*flood\\s+[\\w,) ]+

Or if you want to match any character you could use a dot instead of a character class.

According to your comment, you might use a positive lookbehind:

(?<=\\(13\\. Deductible\\))\\s*(\\s*flood\\s+[\\w,) ]+)+

Demo