用单词而不是char计算字符串

Question

I am working on this code in which it can identify the word listed below from the Web Browser. Those words will turn into asterisk once they are identified and will count how many words were replaced but it didn't work. Someone can help?

Here is my code:

   private void button1_Click(object sender, EventArgs e)
    {
        webBrowser1.Navigate(txbAdress.Text);
        webBrowser1.DocumentCompleted += webBrowser1_DocumentCompleted;
    }

    private void webBrowser1_DocumentCompleted(object sender, WebBrowserDocumentCompletedEventArgs e)
    {
        IHTMLDocument2 doc2 = webBrowser1.Document.DomDocument as IHTMLDocument2;
        StringBuilder html = new StringBuilder(doc2.body.outerHTML);


        string query;
        query = @"

select Word from ListWords ";

        List<string> words = new List<string>();

        DataSet ds;
        DataRow drow;

        ds = DatabaseConnection.Connection1(query);
        int index, total;

        total = ds.Tables[0].Rows.Count;

        string current_word;

        for (index = 0; index < total; index++ )
        {
            drow = ds.Tables[0].Rows[index];
            current_word = drow.ItemArray.GetValue(0).ToString();

            words.Add(current_word);
        }

        Console.WriteLine(query);


        Console.WriteLine("array:" + words);
        foreach (String key in words)
        {
           // String substitution = "<span style='background-color: rgb(255, 0, 0);'>" + key + "</span>";

            int len = key.Length;
            string replace = "";

            for ( index = 0; index < len; index++)
            {
                replace += "*";
            }

            html.Replace(key, replace);
            //count++;
        }

        //Console.WriteLine("Total number of words: " + count);


        doc2.body.innerHTML = html.ToString();
    }

Answer 1

Just count them before you replace them

Given

public int CountOccurrences(string source, string match)
{
   var pos = 0;
   var count = 0;
   while ((pos < source.Length) && (pos = source.IndexOf(match, pos, StringComparison.Ordinal)) != -1)
   {
      count++;
      pos += match.Length;
   }

   return count;
}

Example

var count = CountOccurrences(html,key);
html.Replace(key, substitution);