Iterating through files being read in by C# application

I am building a Winforms application with C# and there are 3 files I will be reading in and then iterating over them to perform some function to verify them. I’m unable to iterate and can’t seem to figure it out as I am learning Winforms and C#.

// store each file path into a string
string nailAssignmentResult = textBox1.Text;
string nailFixtureResult = textBox2.Text;
string nailContactResult = textBox3.Text;

The declaration above stores the file path from 3 textboxes into string variables for me to iterate through.

I have tried a foreach loop and for loop but I can’t seem to figure out how to iterate through them. I would like to parse the information in each file into list separate by a space.

namespace FixtureReports
{
    public partial class btnFileSelect : Form
    {
        // contructor
        public btnFileSelect()
        {
            InitializeComponent();
        }

        // this will do the verification 
        private void btnVerify_Click(object sender, EventArgs e)
        {
            // clear textbox each time its clicked
            results.Clear();

            //store each file path into a string
            string nailAssignmentResult = textBox1.Text;
            string nailFixtureResult = textBox2.Text;
            string nailContactResult = textBox3.Text;

            // error for if all three paths are empty 
            TextBox errorMessage = results;
            if (nailAssignmentResult == "" && nailFixtureResult == "" && nailContactResult == "")
                errorMessage.Text = "ERROR: Cannot have empty path for all three reports!!";

            // verifying each file path exists
            if (File.Exists(nailAssignmentResult))
                errorMessage.AppendText("Nail Assignment Report Found");

            if (File.Exists(nailFixtureResult))
                errorMessage.AppendText("\r\nNail Fixture Report Found");

            if (File.Exists(nailContactResult))
                errorMessage.AppendText("\r\nNail Contact List Report Found");


            // grab each file and iterate through each of them 

            // parse the contents into a list separated by a space horizontally

            // for each line of data, what needs to be compared

            // take in receiver pin and plug into brians function to get pylon

            // compare to existing pylon designation in report and see if it matches

            // have a counter for how many were correct 

            // if incorrect, display pylon blocks and receiver pins
        }

        // prompt for file selection
        private void nailFixtureBtn_Click(object sender, EventArgs e)
        {
            OpenFileDialog openFileDialog = new OpenFileDialog();

            if (openFileDialog.ShowDialog() == DialogResult.OK)
            {
                textBox1.Text = openFileDialog.FileName;
            }
        }

        // prompt for file selection
        private void nailAssignmentBtn_Click(object sender, EventArgs e)
        {
            OpenFileDialog openFileDialog = new OpenFileDialog();

            if (openFileDialog.ShowDialog() == DialogResult.OK)
            {
                textBox2.Text = openFileDialog.FileName;
            }
        }

        // prompt for file selection
        private void nailContactBtn_Click(object sender, EventArgs e)
        {
            OpenFileDialog openFileDialog = new OpenFileDialog();

            if (openFileDialog.ShowDialog() == DialogResult.OK)
            {
                textBox3.Text = openFileDialog.FileName;
            }
        }
    }
}

>Solution :

In order to "iterate" you need a collection. You can create a simple array from the three variables:

var files = new[] {nailAssignmentResult, nailFixtureResult, nailContactResult};

and iterate over that, but if you have the "processing" in a function where you can just pass in the filename (and whatever other information is neeed, then you don’t need to iterate:

var assignmentResults = ProcessFile(nailAssignmentResult);
var fixtureResults = ProcessFile(nailFixtureResult);
var contractResults = ProcessFile(nailContactResult);

These are only two options – there are many ways that this could be done, including creating an iterator function that uses yield return to return each value, but I see no need for anything fancier that a simple array of the values.