title: Jquery Change attr of val before appending
body: <p>I have a textarea field where users can enter an youtube embed code, then on submit i grab the val of the textarea and append it to body. I want to add ?id=123 to the end of the src in the embed code before i append it to body. What is the easiest way to do this. The appended value should be the iframe code with the modified src</p>
  
  <p>Embed code looks like </p>
  
  <pre><code>&lt;iframe title="YouTube video player" width="480" height="390" src="http://www.youtube.com/embed/aemXgP-2xyg" frameborder="0" allowfullscreen&gt;&lt;/iframe&gt;
  </code></pre>
  
  <h1>UPDATED CODE</h1>
  
  <pre><code>                var value = $('textarea').val();
                  var wmode = '?id=123';
                  var value1 = $(value).attr("src", $(value).attr("src") + wmode);                 
                  var code = $('&lt;div class="abs embed" id="embedId"&gt;' + value1 + '&lt;span class="move"&gt;&lt;/span&gt;&lt;/div&gt;');                 
                  $(code).appendTo(...
  </code></pre>