title: How to iterate over a JavaScript object?
body: <p>I have an object in JavaScript:</p>
  
  <pre><code>{
      abc: '...',
      bca: '...',
      zzz: '...',
      xxx: '...',
      ccc: '...',
      // ...
  }
  </code></pre>
  
  <p>I want to use a <code>for</code> loop to get its properties. And I want to iterate it in parts (not all object properties at once).</p>
  
  <p>With a simple array I can do it with a standard <code>for</code> loop:</p>
  
  <pre><code>for (i = 0; i &lt; 100; i++) { ... } // first part
  for (i = 100; i &lt; 300; i++) { ... } // second
  for (i = 300; i &lt; arr.length; i++) { ... } // last
  </code></pre>
  
  <p>But how to do it with objects?</p>