title: Removing un-supported chars from string
body: <p>I have a json string returned from a server with a list of songs, but the encoding it uses is different to that of WP7 (I think).</p>
  
  <p>When I load the string into a textblock on the device is has the typical windows empty white square, but in VS in the element inspector it isn't shown, nor is it in the json file when I open it in sublime (there should be a char between the n and t in "cant"):</p>
  
  <p><img src="https://i.stack.imgur.com/gQCpv.png" alt="Sublime 3 Text"></p>
  
  <p>But when I open it in a hex editor I see this:</p>
  
  <p><img src="https://i.stack.imgur.com/UKlwL.png" alt="enter image description here"></p>
  
  <p>So my question is how can I fix this, without making a blacklist of unsupported bytes and replaceing them every-time I grab the json file?</p>