我正在用C#构建一个Winforms应用程序，我将阅读3个文件，然后迭代它们以执行一些功能来验证它们。我无法迭代，似乎无法弄清楚，因为我正在学习Winforms和C#。

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

上面的声明将3个文本框中的文件路径存储到字符串变量中，以便我进行迭代。
我已经尝试了foreach循环和for循环，但我似乎不知道如何迭代它们。我想把每个文件中的信息解析成一个由空格分隔的列表。

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;
            }
        }
    }
}