Deleting alternate rows from the text file using c#

Question

Im doing a project where i have to read the datas from a .txt file and then insert each line into a table using query.

Now for example the contents of the text file would be

11111

1111x

22222

2222x

33333

3333x

and so on.

Now as you can see that the alternate row is almost repetitive so i would like to remove alternate rows so that the available data becomes

11111

22222

33333

and then process the rest of my codes.

Is there any way i can do that?

So far i have been using the Array list to get this

using (StreamReader sr = new StreamReader(Server.MapPath("03122013114450.txt"), true))
        {

            string txtValues = sr.ReadToEnd();
            string[] txtValuesArray1 = Regex.Split(txtValues, "\r\n");



            ArrayList array = new ArrayList();
            foreach (string value in txtValuesArray1)
            {
                array.Add(value);
            }

            for (int i = 0; i < array.Count; i++)
            {
                if (array.Count % 2 != 0)
                    array.RemoveAt(i + 2);
                else
                    array.RemoveAt(i + 1);
            }
        }

The basic idea is to delete the alternate rows wether it be from the index of the arraylist of from the text file.

Answer 1

Just tried this with LINQ

string[] lines = File.ReadAllLines("your_file_name");
var result = lines.Where((s, idx) => idx % 2 == 0);

of course, if your file is very big, then you need to work line by line and skip the not required lines while reading