title: Using LINQ to parse the numbers from a string
body: <p>Is it possible to write a query where we get all those characters that could be parsed into int from any given string?</p>
  
  <p>For example we have a string like: <code>"$%^DDFG 6 7 23 1"</code> </p>
  
  <p>Result must be <code>"67231"</code></p>
  
  <p>And even slight harder: Can we get only first three numbers?</p>