Question

I am creating a website which include a comment area for users. Example a guestbook or a product review. And I want to restrict a user on posting inappropriate languages on the comment area. For example: vulgarities.

If the user input any vulgarities, the characters would be replace by * . *Example – from stupid to s * * * * **.

I had been researching on related website but it was unfruitful. Suggestions or tutorials on this would be greatly appreciated.

Answer 1

There is no way to fully stop “bad language” from being used but you can try to prevent it by creating a text file that contains a bad word in every line. Then load the list of words from the file to a List<String> in your program. You can do so by doing the following:

// The list of swear words
List<string> swearWords = new List<string>();

private void GetSwearWords()
{
    // Get the path to the file that has the swear words list
    string path = <File Path>;

    // Open the text file
    TextReader reader = new StreamReader(path);

    // Loop through each line in the file.
    string line = "";
    while ((line = reader.ReadLine()) != null)
    {
       // Lower cases word and removes whitespaces
       string word = line.Trim().ToLower();

       // Adds the word to the list
       swearWords.Add(word);
    }
}

Then, to determine if a string has one of these bad words you do the following:

private bool HasSwearWord(string text)
{
    // Splits words, removes whitespace and any punctuation
    string[] wordArray = Regex.Split(text, @"\W+");

    // Check if any word in the string is a swear word
    foreach (string word in wordArray)
    {
        if (swearWords.Contains(word.ToLower()))
        {
            return true;
        }
    }
    return false;
}