ASP.NET XML data binding

We can bind an XML file to the list control.


An XML file

There is a file named "countries.xml" XML file:

<?xml version="1.0" encoding="ISO-8859-1"?>

<countries>

<country>
<text>Norway</text>
<value>N</value>
</country>

<country>
<text>Sweden</text>
<value>S</value>
</country>

<country>
<text>France</text>
<value>F</value>
</country>

<country>
<text>Italy</text>
<value>I</value>
</country>

</countries>

Check the XML file: countries.xml


Bind DataSet to List Controls

First, import the "System.Data" namespace. We need this namespace to work with DataSet objects. The following instruction is included in the top of the x page:

<%@ Import Namespace="System.Data" %>

Next, create a DataSet for the XML file, and when the page first loads this XML file loading DataSet:

<script runat="server">
sub Page_Load
if Not Page.IsPostBack then
dim mycountries=New DataSet
mycountries.ReadXml(MapPath("countries.xml"))
end if
end sub

To bind data to a RadioButtonList control, first create a RadioButtonList control in an x page (without any asp: ListItem elements):

<html>
<body>

<form runat="server">
<asp:RadioButtonList id="rb" runat="server" AutoPostBack="True" />
</form>

</body>
</html>

Then add the script to create XML DataSet, and binds the value to the XML DataSet RadioButtonList control:

<%@ Import Namespace="System.Data" %>

<script runat="server">
sub Page_Load
if Not Page.IsPostBack then
dim mycountries=New DataSet
mycountries.ReadXml(MapPath("countries.xml"))
rb.DataSource=mycountries
rb.DataValueField="value"
rb.DataTextField="text"
rb.DataBind()
end if
end sub
</script>

<html>
<body>

<form runat="server">
<asp:RadioButtonList id="rb" runat="server"
AutoPostBack="True" onSelectedIndexChanged="displayMessage" />
</form>

</body>
</html>

Then we add a subroutine, when a user clicks on an item in the RadioButtonList control when the subroutine is executed. When a radio button is clicked, label will appear in the line of text:

Examples

<%@ Import Namespace="System.Data" %>

<script runat="server">
sub Page_Load
if Not Page.IsPostBack then
dim mycountries=New DataSet
mycountries.ReadXml(MapPath("countries.xml"))
rb.DataSource=mycountries
rb.DataValueField="value"
rb.DataTextField="text"
rb.DataBind()
end if
end sub

sub displayMessage(s as Object,e As EventArgs)
lbl1.text="Your favorite country is: " & rb.SelectedItem.Text
end sub
</script>

<html>
<body>

<form runat="server">
<asp:RadioButtonList id="rb" runat="server"
AutoPostBack="True" onSelectedIndexChanged="displayMessage" />
<p><asp:label id="lbl1" runat="server" /></p>
</form>

</body>
</html>

The demonstration >>