Prevent C# Rich Text Box from converting Asian characters to Hexadecimal

Question

I have a simple C# Windows Form app that converts rich text (pasted from PDF or DOC) into RTF markup. However whenever I paste in Asian characters like this: ありがとうございました the RTF markup converts the characters to their hexadecimal equivalents like this: \'82\'a0\'82\'e8\'82\'aa\'82\'c6\'82\'a4\'82\'b2\'82\'b4\'82\'a2\'82\'dc\'82\'b5\'82\'bd

Anyone know if it's possible to prevent this and have the RTF markup retain the actual Asian characters? I know it's theoretically possible because if I paste the actual characters into the RTF markup window they do not get converted.

Per request here's the actual code that pushes the RTF text into a plain text field ... which is the point where the Asian characters get converted:

private void rtfBox_TextChanged(object sender, EventArgs e){
    plainTextBox.Text = rtfBox.Rtf.ToString();
}

Source of the app here if anyone wants to see further: https://github.com/cemerson/RTFMarkupHelper

Related/Possible duplicates:

• Best way to decode hex sequence of unicode characters to string
• How to output unicode string to RTF (using C#)
• How to convert a string to RTF in C#?
• Output RTF special characters to Unicode
• Display of Asian characters (with Unicode): Difference in character spacing when presented in a RichEdit control compared with using ExtTextOut
• Converting Unicode strings to escaped ascii string
• How can I decode HTML characters in C#?
• How to encode and decode Broken Chinese/Unicode characters?

Answer 1

It is preserving the Asian characters. The hexidecimal encodes unicode values that aren't represented directly in the ANSI encoding used by the RTF spec. Add the following code under a "Save RTF" Button and you'll be able to save the file as a .rtf file, and then open it in wordpad/etc.

    private void button6_Click(object sender, EventArgs e)
    {
        SaveFileDialog sfd = new SaveFileDialog();
        sfd.Filter = "RTF File|*.rtf";
        sfd.DefaultExt = ".rtf";
        if (sfd.ShowDialog() == DialogResult.OK)
        {
            FileInfo fi = new FileInfo(sfd.FileName);
            StreamWriter sw = new StreamWriter(fi.OpenWrite());
            sw.Write(textBox.Text);
            sw.Close();
        }
    }