help exporting text

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using System.IO; 

namespace TextBoxToFile
{

     public partial class Form1 : Form
     {

          public Form1()
          {
               InitializeComponent();
          }

 
          private void tsbSave_Click(object sender, EventArgs e)
          {
               saveFileDialog1.Title = "Open LUA File";
               saveFileDialog1.Filter = "LUA | *.lua";
               saveFileDialog1.DefaultExt = "lua";
               saveFileDialog1.FileName = "";
               saveFileDialog1.ShowDialog();

               if (saveFileDialog1.FileName == "")
                    return;

               StreamWriter sw;
               FileStream fs;

               string fName = saveFileDialog1.FileName;
               fs = new FileStream(fName, FileMode.OpenOrCreate);
               sw = new StreamWriter(fs);
               sw.Write(txtContent.Text);
               sw.Close();
               fs.Close();
          }

          private void tsbOpen_Click(object sender, EventArgs e)
          {
               openFileDialog1.Title = "Open LUA File";
               openFileDialog1.Filter = "LUA | *.lua";
               openFileDialog1.DefaultExt = "lua";
               openFileDialog1.FileName = "";
               openFileDialog1.ShowDialog();

               if (openFileDialog1.FileName == "")
                    return;

               FileStream fs = new FileStream(openFileDialog1.FileName, 
               FileMode.Open, FileAccess.Read);
               StreamReader sr = new StreamReader(fs);

               txtContent.Text = sr.ReadToEnd();

               sr.Close();
               fs.Close();
          }
     }
}