title: Free/open source code editor UI control for .Net
body: <p>I'm looking for a <em>free</em>, <em>syntax-highlighting</em>, possibly <em>autocompleting</em> <strong><em>"Programmer's textbox"</em></strong> style control for use in a Visual Studio Windows Forms or WPF project. It should work with C# and self-defined languages, and the licence should permit its use in a closed, in-house development tool.</p>
  
  <p>There are pay-for solutions available - something like <a href="http://www.syncfusion.com/products/user-interface-edition/windows-forms/Edit" rel="noreferrer">http://www.syncfusion.com/products/user-interface-edition/windows-forms/Edit</a> would work fine - but I am looking for something simpler, and would prefer not to pay for unnecessary functionality. Any ideas?</p>