如何计算字符串中干扰词的数量？

Question

Suppose I have a list of noise words...

string[] noise = new[] {"and", "it", "in"}; // etc, etc

...and I have a string s . I want to know how many noise words exist in s .

I know can do this by splitting s on spaces, then looping through the resultant array checking for matches in noise , but this seems like a very inefficient way of doing it. It feels like there ought to be a neat RegEx or Linq way to do it.

Any suggestions?

Answer 1

LINQ isn't more efficient than a loop but often more readable and concise and i guess that's what you wanted. In this case you can use Enumerable.Count and Contains :

int countNoiseWords = s.Split().Count(noise.Contains);

The case-insensitive way:

int countNoiseWords = s.Split()
    .Count(w => noise.Contains(w, StringComparer.InvariantCultureIgnoreCase));

If the noise -list is very long you should consider to use a HashSet<string> instead of a list.