get an array of "val" attributes values from the rows of a table
<pre><code>&lt;table id ='t1'&gt;
&lt;tr val='1'&gt;&lt;/tr&gt;
&lt;tr val='2'&gt;&lt;/tr&gt;
&lt;tr val='3'&gt;&lt;/tr&gt;
&lt;tr val='4'&gt;&lt;/tr&gt;
&lt;table&gt;
</code></pre>

<p>how to get from this an array = 1,2,3,4</p>
