Set RTF text into WPF RichTextBox control

I have this RTF text:

{\rtf1\ansi\ansicpg1252\deff0\deflang1033{\fonttbl{\f0\fnil\fcharset0 Arial;}}
{\colortbl ;\red0\green0\blue0;\red255\green0\blue0;}
\viewkind4\uc1\pard\qc\cf1\fs16 test \b bold \cf2\b0\i italic\cf0\i0\fs17 
\par }

How to set this text into WPF RichTextBox?

Solution:

public void SetRTFText(string text)
{
    MemoryStream stream = new MemoryStream(ASCIIEncoding.Default.GetBytes(text));
    this.mainRTB.Selection.Load(stream, DataFormats.Rtf);
}