passing selected value of a dropdownlist to a parameter in aspx
<p>I have a grid and dropdownlist.I want to filter values in a grid by the selection of dropdownlist.How Can i do this?
My code is like this</p>

<pre><code>&lt;asp:DropDownList ID="DDLVisitedVol" runat="server" AutoPostBack="true" DataSourceID="DsVisitedVol"
            DataTextField="VisitedVol" DataValueField="VisitedVol" 
            Width="244px"&gt;
        &lt;/asp:DropDownList&gt;

 &lt;asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString=""
           ProviderName=""
            SelectCommand="SELECT [ID],[UserName], [Email], [visitedVol] FROM [HitTracker] where visitedVol=@VisitedVol "&gt;
        &lt;SelectParameters&gt;
                &lt;asp:Parameter Name="VisitedVol" Type="String"/&gt;
        &lt;/SelectParameters&gt;
</code></pre>

<p>How can i pass the selected value of dropdown list to @VisitedVol  .
If anyone knows pls help me.
tHANK YOU</p>
