C# text file search for specific word and delete whole line of text that contains that word

Question

Basically I have a text file that I read in and display in a rich text box, which is fine, but I then want to be able to search through the text for a specific word and delete the whole line of text that contains this word. I can search through the text to see if the word exists or not but I cannot figure out how to delete the whole line. Any help would be great.

Answer 1

We can convert the string to an array of lines, work over it, and convert back:

string[] dados_em_lista = dados_em_txt.Split(
                        new[] { "\r\n", "\r", "\n" },
                        StringSplitOptions.None
                    );

var nova_lista = dados_em_lista.Where(line => !line.Contains(line_to_remove)).ToArray();

dados_em_txt = String.Join("\n", nova_lista);

Answer 2

You can do it easily without LINK

                string search_text = text;
                string old;
                string n="";
                StreamReader sr = File.OpenText(FileName);
                while ((old = sr.ReadLine()) != null)
                {
                    if (!old.Contains(search_text))
                    {
                        n += old+Environment.NewLine;  
                    }
                }
                sr.Close();
                File.WriteAllText(FileName, n);