Don't have the page refresh after selectedindexchanged of dropdown list?
<p>I'm working with two dropdown boxes after a user selects the first required drop down based on what they choose the other drop down will load the final list. I have that working but I don't want the page to reload on once the first dropdown option is picked is there a way around this below is my test code</p>

<p><div class="snippet" data-lang="js" data-hide="false">
<div class="snippet-code">
<pre class="snippet-code-js lang-js prettyprint-override"><code>Behind code

protected void Page_Load(object sender, EventArgs e)
        {
            if (!IsPostBack)
            {
                DropDownList1.Items.Add(new ListItem("3 Days", "3 Days"));
                DropDownList1.Items.Add(new ListItem("4 Days", "4 Days"));
                DropDownList1.Items.Add(new ListItem("5 Days", "5 Days"));
                DropDownList1.Items.Add(new ListItem("7 Days", "7 Days"));
            }
        }

        protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)
        {
            DropDownList2.Items.Clear();
            DropDownList3.Items.AddRange(GetListItems(DropDownList1.SelectedValue));
        }

        private ListItem[] GetListItems(string value)
        {
            var items = new List
                &lt;ListItem&gt;
                ();

            if (value == "3 Days")
            {
                DropDownList2.Items.Add(new ListItem("1", "1"));
            }

            if (value == "4 Days")
            {
                DropDownList2.Items.Add(new ListItem("2", "2"));
            }

            if (value == "5 Days")
            {
                DropDownList2.Items.Add(new ListItem("3", "3"));
            }

            if (value == "7 Days")
            {
                DropDownList2.Items.Add(new ListItem("4", "4"));
            }
            return items.ToArray();
        }</code></pre>
<pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;div class="1"&gt;
&lt;asp:DropDownList ID="DropDownList1" runat="server" AutoPostBack="True" OnSelectedIndexChanged="DropDownList1_SelectedIndexChanged"&gt;
  &lt;asp:ListItem Text="Select..." Value="No selection made"&gt;&lt;/asp:ListItem&gt;
&lt;/asp:DropDownList&gt;
&lt;/div&gt;
&lt;div class="1"&gt;
  &lt;asp:DropDownList ID="DropDownList2" runat="server"&gt;
    &lt;asp:ListItem Text="Select..." Value="No selection made"&gt;&lt;/asp:ListItem&gt;
  &lt;/asp:DropDownList&gt;
&lt;/div&gt;</code></pre>
</div>
</div>
</p>