How to add a value to a existing .csv file

Question

I have information in a .csv file that I at a click of a button, I could just add 1 to that number.

So say this is my data table:

Years last paid:
2012
2012
2012
2012

and at a click of a button, on the selected columns

Years last paid: 
2013
2013
2012
2013 

So in Laymans terms, how do I just add 1 to a selected column when I press a button

I honestly dont have an attempt because I dont know how to google search it, if there are any questions please ask, I have to be up in 3 hours to present this

Answer 1

var lines=File.ReadAllLines(path)
              .Select(x=>Regex.IsMatch(x,@"\d+")?(int.Parse(x)+1).ToString():x);
File.WriteAllLines(path,lines);

Answer 2

try this

List<string> str = File.ReadAllText(@"completefilepath").Split('\n').ToList();
List<string> updatedValues =   new List<string>();
foreach (var value in str)
{
      int val = 0;
      if (int.TryParse(value, out val))
      {
         updatedValues.Add((val + 1).ToString());        
      }
}

File.WriteAllLines(@"completefilepath", updatedValues);

Answer 3

private static void UpdateFile(int selected)
    {
        var lines = File.ReadAllLines("test.csv");
        lines[selected] = (Convert.ToInt32(lines[selected]) + 1).ToString();
        File.WriteAllLines("test.csv", lines);
    }

Answer 4

How are you presenting the current values of the .csv file? How you are selecting the column and row you want to edit.

Regards.

Answer 5

Well you can try using some libraries for parsing CSV files. The one I am using is: THIS ONE . It has CSV writer and reader, easy to use and for my purposes its perfect. This just a suggestion I am not sure if it is going to work for your case but you can see the example in the website.I hope I helped :) Good luck with the project. I you decide to use this library and you have some difficulties. Send me an email and I will try to help :)