Question

i have a radio button list that on selecting, queries a table and displays data in a textarea. now i’m trying to enhance my code so that the value of the radio button is displayed within the URL. that way i can send users links to content displayed by the radio selection (i.e. articles).

So far i’ve been able to place the “Article_PK” within the url successfully when the user makes a selection. now i’m just stuck on how to get my databind working again. so basically, i need to read in the value of the “Article_PK” in the url to display the data within the textarea. need someone with some mad coding skills to save the day!

code behind ——–

public partial class frm_Articles : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {


        if (Page.IsPostBack == false)
        {


            RadioButtonList1.SelectedIndex = 0;
            RadioButtonList1.DataBind();

        }

        else
        {

            string strRedirect;

            strRedirect = "frm_Articles.aspx?Article_PK=" + RadioButtonList1.SelectedValue.ToString();

            Response.Redirect(strRedirect);


        }
    }  



    protected void SqlDataSource2_Selecting(object sender, SqlDataSourceSelectingEventArgs e)
    {

  //    

    }
    protected void SqlDataSource1_Selecting(object sender, SqlDataSourceSelectingEventArgs e)
    {
        try{
        e.Command.Parameters["@URL_FK"].Value =  Session["URL_PK"];


        }
     catch (Exception ex)
     {

     }


    }



}

—– aspx

  <tr valign="top">
        <td  width="75%">

        <!-- Body -->
            <asp:DetailsView ID="DetailsView3" runat="server" AutoGenerateRows="False" DataSourceID="SqlDataSource2" Height="100%" Width="100%" GridLines="None">
                <Fields>


                    <asp:TemplateField HeaderText="ArticleText" ShowHeader="False" SortExpression="ArticleText">
                        <EditItemTemplate>
                            <asp:TextBox ID="TextBox1" runat="server" Text='<%# Bind("ArticleText") %>'></asp:TextBox>
                            <asp:RequiredFieldValidator ID="RequiredFieldValidator1" runat="server" ControlToValidate="TextBox1" ErrorMessage="*"></asp:RequiredFieldValidator>
                        </EditItemTemplate>
                        <InsertItemTemplate>
                            <asp:TextBox ID="TextBox1" runat="server" Text='<%# Bind("ArticleText") %>'></asp:TextBox>
                            <asp:RequiredFieldValidator ID="RequiredFieldValidator1" runat="server" ControlToValidate="TextBox1" ErrorMessage="*"></asp:RequiredFieldValidator>
                        </InsertItemTemplate>
                        <ItemTemplate>

                <%# Eval("ArticleText") %>


                        </ItemTemplate>
                    </asp:TemplateField>
                </Fields>
            </asp:DetailsView>
            <asp:SqlDataSource ID="SqlDataSource2" runat="server" ConnectionString="<%$ ConnectionStrings:CSFConnectionString %>" SelectCommand="SELECT [ArticleText], [Title] FROM [TEST_Article] WHERE ([Article_PK] = @Article_PK)" onselecting="SqlDataSource2_Selecting">
                <SelectParameters>
                    <asp:ControlParameter ControlID="RadioButtonList1" DefaultValue="1" Name="Article_PK" PropertyName="SelectedValue" Type="Int32" ConvertEmptyStringToNull="True" />
                </SelectParameters>
            </asp:SqlDataSource>
            </td>
            <td  width="25%" align="left" valign="top">
                                                <asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="<%$ ConnectionStrings:TESTConnectionString %>" SelectCommand="SELECT Article_PK, ArticleText, Score, Title, Url_FK FROM TEST_Article WHERE (Url_FK = @URL_FK)" onselecting="SqlDataSource1_Selecting">
                                                    <SelectParameters>
                                                        <asp:Parameter DefaultValue="0" Name="Url_FK" Type="Int32" />
                                                    </SelectParameters>
                                                </asp:SqlDataSource>
                                                <h2>Articles</h2>
                                                <h2>Select an article below:</h2>
                                                <asp:RadioButtonList ID="RadioButtonList1" runat="server" AutoPostBack="True" DataSourceID="SqlDataSource1" DataTextField="Title" DataValueField="Article_PK">
                                                </asp:RadioButtonList>
                                                <br />

                                            </td></tr>

Answer 1

If you didn’t build anything in your PageLoad event to handle the query string, then nothing will happen when the controls does a postback.

Inside your pageLoad event you want something like:

if(IsPostBack)
{
    if(Request.QueryString["URL_PK"] != null)
    {
    int url_pk;
    if(int.TryParse(Request.QueryString["URL_PK"].ToString(), out url_pk)
    {
         //do whatever you need to do with url pk here
    }
}

Set your radio buttons to have autopostback="true" and you should get the desired effect.