How To Create A Notepad In C# Windows Form

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the code:

private string FileName = string.Empty; //put this line of code at a form level

==================================================

OpenFileDialog open = new OpenFileDialog();

open.Filter = "Text Files (.txt)|*.txt|All Files (*.*)|*.*";
open.Title = "Open File";
open.FileName = "";

if (open.ShowDialog() == DialogResult.OK)
{
    // save the opened FileName in our variable
    this.FileName = open.FileName;
    this.Text = string.Format("{0}", Path.GetFileNameWithoutExtension(open.FileName));
    StreamReader reader = new StreamReader(open.FileName);
    richTextBox1.Text = reader.ReadToEnd();
    reader.Close();
}

==================================================

SaveFileDialog saving = new SaveFileDialog();

saving.InitialDirectory = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments);

saving.Filter = "Text Files (.txt)|*.txt|All Files (*.*)|*.*";
saving.Title = "Save As";
saving.FileName = "Untitled";

if (saving.ShowDialog() == DialogResult.OK)
{
    // save the new FileName in our variable
    this.FileName = saving.FileName;
    StreamWriter writing = new StreamWriter(saving.FileName);
    writing.Write(richTextBox1.Text);
    writing.Close();
}

==================================================

if (string.IsNullOrEmpty(this.FileName)) { // call SaveAs saveAsToolStripMenuItem_Click(sender, e); } else { // we already have the filename. we overwrite that file StreamWriter writer = new StreamWriter(this.FileName); writer.Write(richTextBox1.Text); writer.Close(); } //note: don't copy the "==================================================". also, //make sure you follow closely to the video's instruction when you want to copy all of the code //in this description ... https://www.youtube.com/watch?v=7PFwFI5-hts