Editing a text file, any easier way?

[babbsagg]

I just want to edit a txt and save the edited version.

In this case i replaced all the i's with q's.

Is there an easier way to do this? Without all the casting?

static void Main(string[] args){

     string[] text = File.ReadAllLines("test.txt");
     char[] help;

     for (int i = 0; i < text.Length; i++) {

         help = text[i].ToArray();

         for (int j = 0; j < help.Length; j++){

              if (help[j] == 'i')
                  help[j] = 'q';
         }

         text[i] = new String(help);
                
     }
     File.WriteAllLines("test_alt.txt",text);
}
}

[RhysW]

            List<string> text = new List<string>();
            string filelocation = null;
            if (openFileDialog1.ShowDialog() == DialogResult.OK)
            {
                filelocation = openFileDialog1.FileName.ToString();
            }
            foreach (string line in File.ReadLines(filelocation))
            {
                string addthis;
                if (line.Contains("i"))
                {
                    addthis = line.Replace("i", "j");
                }
                else
                {
                    addthis = line;
                }
                text.Add(addthis);
            }
            File.WriteAllLines(filelocation, text);

there is this method, you throw it once into a string, replace all i's to j's and then write the list back, there is a fiddly bit in the middle where line isnt added but addthis is, beause i couldnt set it as line = line.replace("i ","j"); or the compiler throws a wobbly because line is used for the rest of the loop, so i made the new string addthis that is always added, if the string contains an i they are turned to j's, assigned to addthis, and add this gets added, otherwise addthis is just directly equal to line, im sure there is a neater way of doing this but you asked for me to get rid of the castings so this was a quick throw together.