Selecting an item in the RadioButtonList, how to get a list of items to a ListBox from database in asp.net c#
<p>I have a <code>RadioButtonList</code> and a <code>ListBox</code>. I have bound <code>RadioButtonList</code> to database.
Therefore upon selecting an item in the <code>RadioButtonList</code>, I want to retrieve some data into the <code>ListBox</code>. The code I have tried is :</p>

<pre><code>protected void Page_Load(object sender, EventArgs e)
{
   RadioFill();
}

public void RadioFill()
    {
        SqlDataAdapter mydata = new SqlDataAdapter("SELECT DISTINCT Param_Name FROM Parameter_Value_Master", con);
        DataSet dset = new DataSet();
        mydata.Fill(dset, "Table");
        RadioButtonList1.Items.Clear();
        RadioButtonList1.DataSource = dset.Tables[0];
        RadioButtonList1.DataTextField = dset.Tables[0].Columns["Param_Name"].ColumnName;
        RadioButtonList1.DataBind();
    }

protected void RadioButtonList1_SelectedIndexChanged(object sender, EventArgs e)
{
SqlDataAdapter mydata = new SqlDataAdapter("SELECT Value_Option FROM   Parameter_Value_Master", con);
DataSet dset = new DataSet();
mydata.Fill(dset, "Table");
ListBox1.Items.Clear();
ListBox1.DataSource = dset.Tables[0];
ListBox1.DataTextField = dset.Tables[0].Columns["Value_Option"].ColumnName;
ListBox1.DataBind();
}
</code></pre>

<p>The issue I am facing here is upon selecting an item, the whole panel in which I have placed both my <code>RadioButtonList</code> and <code>ListBox</code> goes invisible.</p>

<p>Kindly help...!! Thankyou...!!</p>
