title: How to read selected text on richTextBox?
body: <p>There is a richTextBox that has string. I want to select a few characters on the richTexBox by mouse and save them in a variable. I use this method:</p>
  
  <pre><code>richTextBox1.SelectedRtf;
  </code></pre>
  
  <p>It shows me selected characters but is has some additional string and i don't want them. How can I remove them?</p>
  
  <p>This is additional string:
  {\rtf1\fbidis\ansi\ansicpg1256\deff0\deflang1065\uc1 }</p>