title: How to check if a string is a natural number?
body: <p>In javascript, how can you check if a string is a natural number (including zeros)?</p>
  
  <p>Thanks</p>
  
  <p>Examples:</p>
  
  <pre><code>'0' // ok
  '1' // ok
  '-1' // not ok
  '-1.1' // not ok
  '1.1' // not ok
  'abc' // not ok
  </code></pre>