Script that looks for doubled(or more) words in text C#

January 18, 2022

So I have a text and I want to get the value and Index of words wich are written down two times or more than two times (not in a row).
Soo I thought about RegEx, but I’m very new in this topic so I really don’t know how to write a pattern that’s working.

Programming language is C#

>Solution :

You can use regular expressions in order to words words: if we define word as

word is a non-empty sequence of Unicode letters

the pattern will be \p{L}+. Test yourself:

using System.Text.RegularExpressions;
...
string text = 
  "some words, with punctuations, with digits and Russian Words: слово и слово";

var words = Regex.Matches(text, @"\p{L}+");

// some, words, with, punctuations, with, digits, and, 
// Russian, Words, слово, и, слово
Console.Write(string.Join(", ", words));

Then query these words with a help of Linq to find out repeated ones:

  using System.Linq;
  using System.Text.RegularExpressions;

  ... 

  string text = 
    "some words, with punctuations, with digits and Russian Words: слово и слово";

  ...

  string[] words = Regex
    .Matches(text, @"\p{L}+")
    .Cast<Match>()
    .GroupBy(match => match.Value, StringComparer.OrdinalIgnoreCase)
    .Where(group => group.Count() > 1)
    .Select(group => group.Key)
    .ToArray();

  // Let's have a look
  Console.Write(string.Join(", ", words));

Outcome: