title: how to access the element inside iframe, from parent document?
body: <pre><code>function contents_nb(name, height) {
      1. document.getElementById('contents_iframe').height = height+'px';
      2. var $currentIFrame = $('#contents_iframe'); 
      3. $currentIFrame.contents().find(".wrap_contents").hide();
      4. $currentIFrame.contents().find(".greetings").fadeIn(2500);
  }
  </code></pre>
  
  <p>this is my jquery syntax.</p>
  
  <p>no.1 ~ 3, it works well.</p>
  
  <p>but line no.4, it doesn't work.</p>
  
  <p>structure of html document inside iframe is ...</p>
  
  <pre><code>&lt;body&gt;
      &lt;div class="wrap_contents"&gt;
          &lt;div class="greetings"&gt;
          &lt;/div&gt;
          &lt;div class="operational_philosophy"&gt;
          &lt;/div&gt;
      &lt;/div&gt;
      &lt;/body&gt;
      &lt;/html&gt;
  </code></pre>
  
  <p>what is the reason? what causes this problem?</p>
  
  <p>and syntax of the parent html document is..</p>
  
  <pre><code>&lt;iframe id="contents_iframe"&gt;&lt;/iframe&gt;
  </code></pre>
  
  <p>what is the problem??
  why can not find class inside class?</p>