drop down list validation
<p>in my form i have three drop down lists to select days. and their corresponding available time. If one selects available day as monday and time morning. then in rest two pair of drop down list morning slot for monday should be disabled. html code is as:</p>

<pre><code>DAY 1:&lt;select id="day1" title="- Select day -" name="wd1" id="wd1" tabindex="14"  &gt;
                          &lt;option  selected&gt;-select-&lt;/option&gt; 
              &lt;option value="1" &gt;Sunday&lt;/option&gt;
                          &lt;option value="2"  &gt;Monday&lt;/option&gt;
                          &lt;option value="3"  &gt;Tuesday&lt;/option&gt;
                          &lt;option value="4"  &gt;Wednesday&lt;/option&gt;
                          &lt;option value="5"  &gt;Thursday&lt;/option&gt;
              &lt;option value="6"  &gt;Friday&lt;/option&gt;
                          &lt;option value="7"  &gt;Saturday&lt;/option&gt;
                          &lt;/select&gt;

TIME 1 :  &lt;select name="tslot1" id="tslot1" tabindex="15"&gt;
 &lt;option  selected&gt;-select-&lt;/option&gt; 
&lt;option&gt;Morning(8-12)&lt;/option&gt;
&lt;option&gt;Afternoon(12-4pm)&lt;/option&gt;
&lt;option&gt;Evening(4-8pm)&lt;/option&gt;&lt;/select&gt;&lt;br&gt;&lt;br&gt;


DAY 2:&lt;select id="day2" title="- Select day -" name="wd2" id="wd2" tabindex="16" &gt;

                          &lt;option  selected&gt;-select-&lt;/option&gt; 
            &lt;option value="1" &gt;Sunday&lt;/option&gt;
                          &lt;option value="2"  &gt;Monday&lt;/option&gt;
                          &lt;option value="3"  &gt;Tuesday&lt;/option&gt;
                          &lt;option value="4"  &gt;Wednesday&lt;/option&gt;
                          &lt;option value="5"  &gt;Thursday&lt;/option&gt;
              &lt;option value="6"  &gt;Friday&lt;/option&gt;
                          &lt;option value="7"  &gt;Saturday&lt;/option&gt;
                          &lt;/select&gt;

TIME 2 :  &lt;select name="tslot2" id="tslot2" tabindex="17" &gt;
 &lt;option  selected&gt;-select-&lt;/option&gt; 
&lt;option&gt;Morning(8-12)&lt;/option&gt;
&lt;option&gt;Afternoon(12-4pm)&lt;/option&gt;
&lt;option&gt;Evening(4-8pm)&lt;/option&gt;&lt;/select&gt;&lt;br/&gt;&lt;br/&gt;

DAY 3:&lt;select select id="day3" title="- Select day -" name="wd3" id="wd3" tabindex="18" &gt;

                          &lt;option  selected&gt;-select-&lt;/option&gt; 
                          &lt;option value="1" &gt;Sunday&lt;/option&gt;
                          &lt;option value="2"  &gt;Monday&lt;/option&gt;
                          &lt;option value="3"  &gt;Tuesday&lt;/option&gt;
                          &lt;option value="4"  &gt;Wednesday&lt;/option&gt;
                          &lt;option value="5"  &gt;Thursday&lt;/option&gt;
              &lt;option value="6"  &gt;Friday&lt;/option&gt;
                          &lt;option value="7"  &gt;Saturday&lt;/option&gt;
                          &lt;/select&gt;

TIME 3 :  &lt;select name="tslot3" id="tslot3" tabindex="19" &gt;
 &lt;option  selected&gt;-select-&lt;/option&gt; 
&lt;option&gt;Morning(8-12)&lt;/option&gt;
&lt;option&gt;Afternoon(12-4pm)&lt;/option&gt;
&lt;option&gt;Evening(4-8pm)&lt;/option&gt;&lt;/select&gt;&lt;br/&gt;&lt;br/&gt; 
</code></pre>

<p>Please do help me with this problem...</p>
