Use of savefiledialog box for saving files

1)Open a windows application.
2)On the form paste a button, richtextbox. also add a savefiledialog.

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

namespace WindowsFormsApplication3
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            saveFileDialog1.Filter = "all files|*.*|text files|*.txt";
            saveFileDialog1.InitialDirectory = "C:\\";

            if (saveFileDialog1.ShowDialog() == DialogResult.OK)
            {
                richTextBox1.SaveFile(saveFileDialog1.FileName, RichTextBoxStreamType.PlainText);
                MessageBox.Show("file saved");
            }
            richTextBox1.Text = "";


        }
    }
}