编写列表项到文本文件c#

我正试图让List保存到文本文件中，我遇到了一个问题。它将保存到文本文件中，但不是所需的所有信息，而是实际显示在ListBox中的信息。建议吗?

namespace Employee_Form
{
public partial class frmMain : Form
{
    FileStream output;
    StreamReader fileReader;
    //StreamWriter fileWriter;
    List<Employee> employeeList = new List<Employee>();

    public frmMain()
    {
        InitializeComponent();
    }
    private void frmMain_Load(object sender, EventArgs e)
    {
    }
    private void openToolStripMenuItem_Click(object sender, EventArgs e)
    {
        OpenFile();
    }
    private void saveAsToolStripMenuItem_Click(object sender, EventArgs e)
    {
        SaveAs();
    }
    private void addNewToolStripMenuItem_Click(object sender, EventArgs e)
    {
        PropertiesOpen();
    }
    private void PropertiesOpen()
    {
        //creates an instance of the Properties Form
        frmProperties myform = new frmProperties();
        DialogResult result = myform.ShowDialog();
    }

    //Opens a file chosen by a user and places information into the listbox
    private void OpenFile()
    {
        OpenFileDialog fileChooser = new OpenFileDialog();
        fileChooser.Title = "Pick a file";
        fileChooser.Filter = "Text Files (*.txt) | *.txt";
        DialogResult result = fileChooser.ShowDialog();
        //
        if (result == DialogResult.Cancel)
        {
            //do nothing
            return;
        }
        string strFileName = fileChooser.FileName;
        try
        {
            //open the file for read access
            output = new FileStream(strFileName, FileMode.Open, FileAccess.Read);
            fileReader = new StreamReader(output);
            //variables to hold read record
            string strInputLine;
            string[] fields;
            //loop to get records and break into fields
            while (fileReader.EndOfStream != true)
            {
                //read record
                strInputLine = fileReader.ReadLine();
                //split the records when read
                fields = strInputLine.Split(',');
                //add records to the list box 
                employeeList.Add(new Employee(fields[1], fields[0], fields[2], 
                                     Convert.ToDouble(fields[3])));
            }
            lstRecords.DataSource = employeeList;
        }
        catch (Exception ex)
        {
            MessageBox.Show(ex.Message);
        }
        finally
        {
            //closes fileReader and output to save Resources
            fileReader.Close();
            output.Close();
        }
    }
    public void SaveAs()
    {
        //create a file dialog
        SaveFileDialog fileChooser = new SaveFileDialog();
        fileChooser.Title = "Choose A Save Location";
        fileChooser.Filter = "Text Files (*txt)|*.txt";
        //open the dialog and get a result
        DialogResult result = fileChooser.ShowDialog();
        //checks if user clicks cancel
        if (result == DialogResult.Cancel)
        {
            return;
        }
        //get the file name from the dialog
        string strFileName = fileChooser.FileName;
        try
        {
            //open the new file for write access
            StreamWriter SaveFile = new StreamWriter(strFileName);
            foreach (var item in employeeList)
            {
                SaveFile.WriteLine(item.ToString());
            }
            SaveFile.Close();
        }
        catch (Exception ex)
        {
            MessageBox.Show(ex.Message);
        }
        finally
        {
            //close resources
            //fileWriter.Close();
            output.Close();
        }
    }
}

对不起，我是新手。有两个表单，第二个是用于编辑/添加新员工的。只需要在ListBox中显示姓和名。下面是我的Employee类:

public class Employee
{
    public string FirstName
    {
        get;
        set;
    }
    public string LastName
    {
        get;
        set;
    }
    public string EmpType
    {
        get;
        set;
    }
    public double Salary
    {
        get;
        set;
    }
    public Employee(string firstName, string lastName, string empType, double salary)
    {
        FirstName = firstName;
        LastName = lastName;
        EmpType = empType;
        Salary = salary;
    }
    public override string ToString()
    {
        return string.Format("{0}, {1}", LastName, FirstName);
    }
}

return string.Format("{0}, {1}", LastName, FirstName);

SaveFile.WriteLine(string.Format("{0}, {1}, {2}, {3}", item.LastName, item.FirstName, item.EmpType, item.Salary));