【C#】利用富文本框打开，保存text文件【源代码】

private void 打开ToolStripMenuItem_Click(object sender, EventArgs e)

        {

            OpenFileDialog open = new OpenFileDialog();

            open.InitialDirectory = "F:\\";     //设置初始目录

            open.Filter = "文本文件(*.txt)|*.*|(*.htm)|*.htm"; //打开htm类型文件或text文件

            open.RestoreDirectory = true;   //设置对话框在关闭前还原当前目录

            open.FilterIndex = 1;

            if (open.ShowDialog() == DialogResult.OK)

            {

                string str = open.FileName;

                StreamReader sr = File.OpenText(str);

                string s;

                while ((s = sr.ReadLine()) != null)

                    this.richTextBox1.Text += s;

                sr.Close();

            }

        }

 

        private void 保存ToolStripMenuItem_Click(object sender, EventArgs e)

        {

            SaveFileDialog save = new SaveFileDialog();

            save.InitialDirectory = "C:\\";

            save.Filter = "(*.txt)|*.*|(*.cs)|*.cs";    //打开cs文件或text文件

            save.RestoreDirectory = true;

            save.FilterIndex = 1;

            if (save.ShowDialog() == DialogResult.OK)

            {

                string str = save.FileName;

                //向指定的文件中追加内容，如果文件不存在，则创建文件

                StreamWriter sw = File.AppendText(str);

                sw.Write(this.richTextBox1.Text);

                sw.Flush();

                sw.Close();

            }

        }